chore: regens API reference docs (#889)

diff --git a/docs/dyn/chat_v1.spaces.messages.html b/docs/dyn/chat_v1.spaces.messages.html
index 6ebea79..6c6aece 100644
--- a/docs/dyn/chat_v1.spaces.messages.html
+++ b/docs/dyn/chat_v1.spaces.messages.html
@@ -75,7 +75,7 @@
 <h1><a href="chat_v1.html">Hangouts Chat API</a> . <a href="chat_v1.spaces.html">spaces</a> . <a href="chat_v1.spaces.messages.html">messages</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#create">create(parent, body, threadKey=None, x__xgafv=None)</a></code></p>
+  <code><a href="#create">create(parent, body=None, threadKey=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Creates a message.</p>
 <p class="toc_element">
   <code><a href="#delete">delete(name, x__xgafv=None)</a></code></p>
@@ -84,17 +84,17 @@
   <code><a href="#get">get(name, x__xgafv=None)</a></code></p>
 <p class="firstline">Returns a message.</p>
 <p class="toc_element">
-  <code><a href="#update">update(name, body, updateMask=None, x__xgafv=None)</a></code></p>
+  <code><a href="#update">update(name, body=None, updateMask=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Updates a message.</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="create">create(parent, body, threadKey=None, x__xgafv=None)</code>
+    <code class="details" id="create">create(parent, body=None, threadKey=None, x__xgafv=None)</code>
   <pre>Creates a message.
 
 Args:
   parent: string, Required. Space resource name, in the form "spaces/*".
 Example: spaces/AAAAMpdlehY (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # A message in Hangouts Chat.
@@ -112,8 +112,8 @@
           # Example: spaces/AAAAMpdlehY/threads/UMxbHmzDlr4
     },
     "space": { # A room or DM in Hangouts Chat. # The space the message belongs to.
-      "displayName": "A String", # Output only. The display name (only if the space is a room).
       "type": "A String", # Output only. The type of a space.
+      "displayName": "A String", # Output only. The display name (only if the space is a room).
       "name": "A String", # Resource name of the space, in the form "spaces/*".
           #
           # Example: spaces/AAAAMpdlehYs
@@ -121,6 +121,242 @@
     "text": "A String", # Plain-text body of the message.
     "fallbackText": "A String", # A plain-text description of the message's cards, used when the actual cards
         # cannot be displayed (e.g. mobile notifications).
+    "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
+        # server.
+    "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
+    "cards": [ # Rich, formatted and interactive cards that can be used to display UI
+        # elements such as: formatted texts, buttons, clickable images. Cards are
+        # normally displayed below the plain-text body of the message.
+      { # A card is a UI element that can contain UI widgets such as texts, images.
+        "cardActions": [ # The actions of this card.
+          { # A card action is
+              # the action associated with the card. For an invoice card, a
+              # typical action would be: delete invoice, email invoice or open the
+              # invoice in browser.
+            "actionLabel": "A String", # The label used to be displayed in the action menu item.
+            "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
+              "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                  # For example, an Apps Script can be invoked to handle the form.
+                "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                    # form submission. This information is echoed back to the bot as part of
+                    # the card click event. The same method name can be used for several
+                    # elements that trigger a common behavior if desired.
+                "parameters": [ # List of action parameters.
+                  { # List of string parameters to supply when the action method is invoked.
+                      # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                      # snooze next week. You might use action method = snooze(), passing the
+                      # snooze type and snooze time in the list of string parameters.
+                    "key": "A String", # The name of the parameter for the action script.
+                    "value": "A String", # The value of the parameter.
+                  },
+                ],
+              },
+              "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                "url": "A String", # The URL to open.
+              },
+            },
+          },
+        ],
+        "sections": [ # Sections are separated by a line divider.
+          { # A section contains a collection of widgets that are rendered
+              # (vertically) in the order that they are specified. Across all platforms,
+              # cards have a narrow fixed width, so
+              # there is currently no need for layout properties (e.g. float).
+            "widgets": [ # A section must contain at least 1 widget.
+              { # A widget is a UI element that presents texts, images, etc.
+                "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
+                    # fields should be set.
+                  { # A button. Can be a text button or an image button.
+                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                      "iconUrl": "A String", # The icon specified by a URL.
+                      "name": "A String", # The name of this image_button which will be used for accessibility.
+                          # Default value will be provided if developers don't specify.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                          # API.
+                    },
+                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                      "text": "A String", # The text of the button.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                    },
+                  },
+                ],
+                "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
+                    # element may also contain some actions such as onclick button.
+                  "contentMultiline": True or False, # If the content should be multiline.
+                  "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
+                  "topLabel": "A String", # The text of the top label. Formatted text supported.
+                  "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
+                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                      "iconUrl": "A String", # The icon specified by a URL.
+                      "name": "A String", # The name of this image_button which will be used for accessibility.
+                          # Default value will be provided if developers don't specify.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                          # API.
+                    },
+                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                      "text": "A String", # The text of the button.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                    },
+                  },
+                  "content": "A String", # The text of the content. Formatted text supported and always required.
+                  "iconUrl": "A String", # The icon specified by a URL.
+                  "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
+                      # are clickable.
+                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                        # For example, an Apps Script can be invoked to handle the form.
+                      "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                          # form submission. This information is echoed back to the bot as part of
+                          # the card click event. The same method name can be used for several
+                          # elements that trigger a common behavior if desired.
+                      "parameters": [ # List of action parameters.
+                        { # List of string parameters to supply when the action method is invoked.
+                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                            # snooze next week. You might use action method = snooze(), passing the
+                            # snooze type and snooze time in the list of string parameters.
+                          "key": "A String", # The name of the parameter for the action script.
+                          "value": "A String", # The value of the parameter.
+                        },
+                      ],
+                    },
+                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                      "url": "A String", # The URL to open.
+                    },
+                  },
+                  "icon": "A String", # An enum value that will be replaced by the Chat API with the
+                      # corresponding icon image.
+                },
+                "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
+                  "aspectRatio": 3.14, # The aspect ratio of this image (width/height). This field allows clients
+                      # to reserve the right height for the image while waiting for it to load.
+                      # It's not meant to override the native aspect ratio of the image.
+                      # If unset, the server fills it by prefetching the image.
+                  "imageUrl": "A String", # The URL of the image.
+                  "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                        # For example, an Apps Script can be invoked to handle the form.
+                      "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                          # form submission. This information is echoed back to the bot as part of
+                          # the card click event. The same method name can be used for several
+                          # elements that trigger a common behavior if desired.
+                      "parameters": [ # List of action parameters.
+                        { # List of string parameters to supply when the action method is invoked.
+                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                            # snooze next week. You might use action method = snooze(), passing the
+                            # snooze type and snooze time in the list of string parameters.
+                          "key": "A String", # The name of the parameter for the action script.
+                          "value": "A String", # The value of the parameter.
+                        },
+                      ],
+                    },
+                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                      "url": "A String", # The URL to open.
+                    },
+                  },
+                },
+                "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
+                  "text": "A String",
+                },
+              },
+            ],
+            "header": "A String", # The header of the section, text formatted supported.
+          },
+        ],
+        "name": "A String", # Name of the card.
+        "header": { # The header of the card. A header usually contains a title and an image.
+          "imageStyle": "A String", # The image's type (e.g. square border or circular border).
+          "imageUrl": "A String", # The URL of the image in the card header.
+          "subtitle": "A String", # The subtitle of the card header.
+          "title": "A String", # The title must be specified. The header has a fixed height: if both a
+              # title and subtitle is specified, each will take up 1 line. If only the
+              # title is specified, it will take up both lines.
+        },
+      },
+    ],
+    "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
+        # user, but any links to images, web pages, videos, etc. included here will
+        # generate preview chips.
     "annotations": [ # Output only. Annotations associated with the text in this message.
       { # Annotations associated with the plain-text body of the message.
           #
@@ -149,8 +385,9 @@
         "userMention": { # Annotation metadata for user mentions (@). # The metadata of user mention.
           "type": "A String", # The type of user mention.
           "user": { # A user in Hangouts Chat. # The user mentioned.
-            "displayName": "A String", # The user's display name.
             "type": "A String", # User type.
+            "domainId": "A String", # Obfuscated domain information.
+            "displayName": "A String", # The user's display name.
             "name": "A String", # Resource name, in the format "users/*".
           },
         },
@@ -161,228 +398,10 @@
             # annotation corresponds to.
       },
     ],
-    "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
-    "cards": [ # Rich, formatted and interactive cards that can be used to display UI
-        # elements such as: formatted texts, buttons, clickable images. Cards are
-        # normally displayed below the plain-text body of the message.
-      { # A card is a UI element that can contain UI widgets such as texts, images.
-        "cardActions": [ # The actions of this card.
-          { # A card action is
-              # the action associated with the card. For an invoice card, a
-              # typical action would be: delete invoice, email invoice or open the
-              # invoice in browser.
-            "actionLabel": "A String", # The label used to be displayed in the action menu item.
-            "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
-              "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                "url": "A String", # The URL to open.
-              },
-              "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                  # For example, an Apps Script can be invoked to handle the form.
-                "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                    # clicked/activated.
-                "parameters": [ # List of action parameters.
-                  { # List of string parameters to supply when the action method is invoked.
-                      # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                      # snooze next week. You might use action method = snooze(), passing the
-                      # snooze type and snooze time in the list of string parameters.
-                    "value": "A String", # The value of the parameter.
-                    "key": "A String", # The name of the parameter for the action script.
-                  },
-                ],
-              },
-            },
-          },
-        ],
-        "sections": [ # Sections are separated by a line divider.
-          { # A section contains a collection of widgets that are rendered
-              # (vertically) in the order that they are specified. Across all platforms,
-              # cards have a narrow fixed width, so
-              # there is currently no need for layout properties (e.g. float).
-            "widgets": [ # A section must contain at least 1 widget.
-              { # A widget is a UI element that presents texts, images, etc.
-                "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
-                    # fields should be set.
-                  { # A button. Can be a text button or an image button.
-                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                      "iconUrl": "A String", # The icon specified by a URL.
-                      "name": "A String", # The name of this image_button which will be used for accessibility.
-                          # Default value will be provided if developers don't specify.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                          # API.
-                    },
-                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                      "text": "A String", # The text of the button.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                    },
-                  },
-                ],
-                "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
-                    # element may also contain some actions such as onclick button.
-                  "contentMultiline": True or False, # If the content should be multiline.
-                  "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
-                  "topLabel": "A String", # The text of the top label. Formatted text supported.
-                  "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
-                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                      "iconUrl": "A String", # The icon specified by a URL.
-                      "name": "A String", # The name of this image_button which will be used for accessibility.
-                          # Default value will be provided if developers don't specify.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                          # API.
-                    },
-                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                      "text": "A String", # The text of the button.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                    },
-                  },
-                  "content": "A String", # The text of the content. Formatted text supported and always required.
-                  "iconUrl": "A String", # The icon specified by a URL.
-                  "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
-                      # are clickable.
-                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                      "url": "A String", # The URL to open.
-                    },
-                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                        # For example, an Apps Script can be invoked to handle the form.
-                      "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                          # clicked/activated.
-                      "parameters": [ # List of action parameters.
-                        { # List of string parameters to supply when the action method is invoked.
-                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                            # snooze next week. You might use action method = snooze(), passing the
-                            # snooze type and snooze time in the list of string parameters.
-                          "value": "A String", # The value of the parameter.
-                          "key": "A String", # The name of the parameter for the action script.
-                        },
-                      ],
-                    },
-                  },
-                  "icon": "A String", # An enum value that will be replaced by the Chat API with the
-                      # corresponding icon image.
-                },
-                "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
-                  "aspectRatio": 3.14, # The aspect ratio of this image (width/height).
-                  "imageUrl": "A String", # The URL of the image.
-                  "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                      "url": "A String", # The URL to open.
-                    },
-                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                        # For example, an Apps Script can be invoked to handle the form.
-                      "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                          # clicked/activated.
-                      "parameters": [ # List of action parameters.
-                        { # List of string parameters to supply when the action method is invoked.
-                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                            # snooze next week. You might use action method = snooze(), passing the
-                            # snooze type and snooze time in the list of string parameters.
-                          "value": "A String", # The value of the parameter.
-                          "key": "A String", # The name of the parameter for the action script.
-                        },
-                      ],
-                    },
-                  },
-                },
-                "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
-                  "text": "A String",
-                },
-              },
-            ],
-            "header": "A String", # The header of the section, text formatted supported.
-          },
-        ],
-        "name": "A String", # Name of the card.
-        "header": { # The header of the card. A header usually contains a title and an image.
-          "imageStyle": "A String", # The image's type (e.g. square border or circular border).
-          "imageUrl": "A String", # The URL of the image in the card header.
-          "subtitle": "A String", # The subtitle of the card header.
-          "title": "A String", # The title must be specified. The header has a fixed height: if both a
-              # title and subtitle is specified, each will take up 1 line. If only the
-              # title is specified, it will take up both lines.
-        },
-      },
-    ],
-    "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
-        # user, but any links to images, web pages, videos, etc. included here will
-        # generate preview chips.
-    "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
-        # server.
     "sender": { # A user in Hangouts Chat. # The user who created the message.
-      "displayName": "A String", # The user's display name.
       "type": "A String", # User type.
+      "domainId": "A String", # Obfuscated domain information.
+      "displayName": "A String", # The user's display name.
       "name": "A String", # Resource name, in the format "users/*".
     },
   }
@@ -419,8 +438,8 @@
             # Example: spaces/AAAAMpdlehY/threads/UMxbHmzDlr4
       },
       "space": { # A room or DM in Hangouts Chat. # The space the message belongs to.
-        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "type": "A String", # Output only. The type of a space.
+        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "name": "A String", # Resource name of the space, in the form "spaces/*".
             #
             # Example: spaces/AAAAMpdlehYs
@@ -428,6 +447,242 @@
       "text": "A String", # Plain-text body of the message.
       "fallbackText": "A String", # A plain-text description of the message's cards, used when the actual cards
           # cannot be displayed (e.g. mobile notifications).
+      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
+          # server.
+      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
+      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
+          # elements such as: formatted texts, buttons, clickable images. Cards are
+          # normally displayed below the plain-text body of the message.
+        { # A card is a UI element that can contain UI widgets such as texts, images.
+          "cardActions": [ # The actions of this card.
+            { # A card action is
+                # the action associated with the card. For an invoice card, a
+                # typical action would be: delete invoice, email invoice or open the
+                # invoice in browser.
+              "actionLabel": "A String", # The label used to be displayed in the action menu item.
+              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
+                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                    # For example, an Apps Script can be invoked to handle the form.
+                  "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                      # form submission. This information is echoed back to the bot as part of
+                      # the card click event. The same method name can be used for several
+                      # elements that trigger a common behavior if desired.
+                  "parameters": [ # List of action parameters.
+                    { # List of string parameters to supply when the action method is invoked.
+                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                        # snooze next week. You might use action method = snooze(), passing the
+                        # snooze type and snooze time in the list of string parameters.
+                      "key": "A String", # The name of the parameter for the action script.
+                      "value": "A String", # The value of the parameter.
+                    },
+                  ],
+                },
+                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                  "url": "A String", # The URL to open.
+                },
+              },
+            },
+          ],
+          "sections": [ # Sections are separated by a line divider.
+            { # A section contains a collection of widgets that are rendered
+                # (vertically) in the order that they are specified. Across all platforms,
+                # cards have a narrow fixed width, so
+                # there is currently no need for layout properties (e.g. float).
+              "widgets": [ # A section must contain at least 1 widget.
+                { # A widget is a UI element that presents texts, images, etc.
+                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
+                      # fields should be set.
+                    { # A button. Can be a text button or an image button.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                  ],
+                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
+                      # element may also contain some actions such as onclick button.
+                    "contentMultiline": True or False, # If the content should be multiline.
+                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
+                    "topLabel": "A String", # The text of the top label. Formatted text supported.
+                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                    "content": "A String", # The text of the content. Formatted text supported and always required.
+                    "iconUrl": "A String", # The icon specified by a URL.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
+                        # are clickable.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
+                        # corresponding icon image.
+                  },
+                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
+                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height). This field allows clients
+                        # to reserve the right height for the image while waiting for it to load.
+                        # It's not meant to override the native aspect ratio of the image.
+                        # If unset, the server fills it by prefetching the image.
+                    "imageUrl": "A String", # The URL of the image.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                  },
+                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
+                    "text": "A String",
+                  },
+                },
+              ],
+              "header": "A String", # The header of the section, text formatted supported.
+            },
+          ],
+          "name": "A String", # Name of the card.
+          "header": { # The header of the card. A header usually contains a title and an image.
+            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
+            "imageUrl": "A String", # The URL of the image in the card header.
+            "subtitle": "A String", # The subtitle of the card header.
+            "title": "A String", # The title must be specified. The header has a fixed height: if both a
+                # title and subtitle is specified, each will take up 1 line. If only the
+                # title is specified, it will take up both lines.
+          },
+        },
+      ],
+      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
+          # user, but any links to images, web pages, videos, etc. included here will
+          # generate preview chips.
       "annotations": [ # Output only. Annotations associated with the text in this message.
         { # Annotations associated with the plain-text body of the message.
             #
@@ -456,8 +711,9 @@
           "userMention": { # Annotation metadata for user mentions (@). # The metadata of user mention.
             "type": "A String", # The type of user mention.
             "user": { # A user in Hangouts Chat. # The user mentioned.
-              "displayName": "A String", # The user's display name.
               "type": "A String", # User type.
+              "domainId": "A String", # Obfuscated domain information.
+              "displayName": "A String", # The user's display name.
               "name": "A String", # Resource name, in the format "users/*".
             },
           },
@@ -468,228 +724,10 @@
               # annotation corresponds to.
         },
       ],
-      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
-      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
-          # elements such as: formatted texts, buttons, clickable images. Cards are
-          # normally displayed below the plain-text body of the message.
-        { # A card is a UI element that can contain UI widgets such as texts, images.
-          "cardActions": [ # The actions of this card.
-            { # A card action is
-                # the action associated with the card. For an invoice card, a
-                # typical action would be: delete invoice, email invoice or open the
-                # invoice in browser.
-              "actionLabel": "A String", # The label used to be displayed in the action menu item.
-              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
-                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                  "url": "A String", # The URL to open.
-                },
-                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                    # For example, an Apps Script can be invoked to handle the form.
-                  "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                      # clicked/activated.
-                  "parameters": [ # List of action parameters.
-                    { # List of string parameters to supply when the action method is invoked.
-                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                        # snooze next week. You might use action method = snooze(), passing the
-                        # snooze type and snooze time in the list of string parameters.
-                      "value": "A String", # The value of the parameter.
-                      "key": "A String", # The name of the parameter for the action script.
-                    },
-                  ],
-                },
-              },
-            },
-          ],
-          "sections": [ # Sections are separated by a line divider.
-            { # A section contains a collection of widgets that are rendered
-                # (vertically) in the order that they are specified. Across all platforms,
-                # cards have a narrow fixed width, so
-                # there is currently no need for layout properties (e.g. float).
-              "widgets": [ # A section must contain at least 1 widget.
-                { # A widget is a UI element that presents texts, images, etc.
-                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
-                      # fields should be set.
-                    { # A button. Can be a text button or an image button.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                  ],
-                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
-                      # element may also contain some actions such as onclick button.
-                    "contentMultiline": True or False, # If the content should be multiline.
-                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
-                    "topLabel": "A String", # The text of the top label. Formatted text supported.
-                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                    "content": "A String", # The text of the content. Formatted text supported and always required.
-                    "iconUrl": "A String", # The icon specified by a URL.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
-                        # are clickable.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
-                        # corresponding icon image.
-                  },
-                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
-                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height).
-                    "imageUrl": "A String", # The URL of the image.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                  },
-                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
-                    "text": "A String",
-                  },
-                },
-              ],
-              "header": "A String", # The header of the section, text formatted supported.
-            },
-          ],
-          "name": "A String", # Name of the card.
-          "header": { # The header of the card. A header usually contains a title and an image.
-            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
-            "imageUrl": "A String", # The URL of the image in the card header.
-            "subtitle": "A String", # The subtitle of the card header.
-            "title": "A String", # The title must be specified. The header has a fixed height: if both a
-                # title and subtitle is specified, each will take up 1 line. If only the
-                # title is specified, it will take up both lines.
-          },
-        },
-      ],
-      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
-          # user, but any links to images, web pages, videos, etc. included here will
-          # generate preview chips.
-      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
-          # server.
       "sender": { # A user in Hangouts Chat. # The user who created the message.
-        "displayName": "A String", # The user's display name.
         "type": "A String", # User type.
+        "domainId": "A String", # Obfuscated domain information.
+        "displayName": "A String", # The user's display name.
         "name": "A String", # Resource name, in the format "users/*".
       },
     }</pre>
@@ -756,8 +794,8 @@
             # Example: spaces/AAAAMpdlehY/threads/UMxbHmzDlr4
       },
       "space": { # A room or DM in Hangouts Chat. # The space the message belongs to.
-        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "type": "A String", # Output only. The type of a space.
+        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "name": "A String", # Resource name of the space, in the form "spaces/*".
             #
             # Example: spaces/AAAAMpdlehYs
@@ -765,6 +803,242 @@
       "text": "A String", # Plain-text body of the message.
       "fallbackText": "A String", # A plain-text description of the message's cards, used when the actual cards
           # cannot be displayed (e.g. mobile notifications).
+      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
+          # server.
+      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
+      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
+          # elements such as: formatted texts, buttons, clickable images. Cards are
+          # normally displayed below the plain-text body of the message.
+        { # A card is a UI element that can contain UI widgets such as texts, images.
+          "cardActions": [ # The actions of this card.
+            { # A card action is
+                # the action associated with the card. For an invoice card, a
+                # typical action would be: delete invoice, email invoice or open the
+                # invoice in browser.
+              "actionLabel": "A String", # The label used to be displayed in the action menu item.
+              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
+                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                    # For example, an Apps Script can be invoked to handle the form.
+                  "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                      # form submission. This information is echoed back to the bot as part of
+                      # the card click event. The same method name can be used for several
+                      # elements that trigger a common behavior if desired.
+                  "parameters": [ # List of action parameters.
+                    { # List of string parameters to supply when the action method is invoked.
+                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                        # snooze next week. You might use action method = snooze(), passing the
+                        # snooze type and snooze time in the list of string parameters.
+                      "key": "A String", # The name of the parameter for the action script.
+                      "value": "A String", # The value of the parameter.
+                    },
+                  ],
+                },
+                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                  "url": "A String", # The URL to open.
+                },
+              },
+            },
+          ],
+          "sections": [ # Sections are separated by a line divider.
+            { # A section contains a collection of widgets that are rendered
+                # (vertically) in the order that they are specified. Across all platforms,
+                # cards have a narrow fixed width, so
+                # there is currently no need for layout properties (e.g. float).
+              "widgets": [ # A section must contain at least 1 widget.
+                { # A widget is a UI element that presents texts, images, etc.
+                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
+                      # fields should be set.
+                    { # A button. Can be a text button or an image button.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                  ],
+                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
+                      # element may also contain some actions such as onclick button.
+                    "contentMultiline": True or False, # If the content should be multiline.
+                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
+                    "topLabel": "A String", # The text of the top label. Formatted text supported.
+                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                    "content": "A String", # The text of the content. Formatted text supported and always required.
+                    "iconUrl": "A String", # The icon specified by a URL.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
+                        # are clickable.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
+                        # corresponding icon image.
+                  },
+                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
+                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height). This field allows clients
+                        # to reserve the right height for the image while waiting for it to load.
+                        # It's not meant to override the native aspect ratio of the image.
+                        # If unset, the server fills it by prefetching the image.
+                    "imageUrl": "A String", # The URL of the image.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                  },
+                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
+                    "text": "A String",
+                  },
+                },
+              ],
+              "header": "A String", # The header of the section, text formatted supported.
+            },
+          ],
+          "name": "A String", # Name of the card.
+          "header": { # The header of the card. A header usually contains a title and an image.
+            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
+            "imageUrl": "A String", # The URL of the image in the card header.
+            "subtitle": "A String", # The subtitle of the card header.
+            "title": "A String", # The title must be specified. The header has a fixed height: if both a
+                # title and subtitle is specified, each will take up 1 line. If only the
+                # title is specified, it will take up both lines.
+          },
+        },
+      ],
+      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
+          # user, but any links to images, web pages, videos, etc. included here will
+          # generate preview chips.
       "annotations": [ # Output only. Annotations associated with the text in this message.
         { # Annotations associated with the plain-text body of the message.
             #
@@ -793,8 +1067,9 @@
           "userMention": { # Annotation metadata for user mentions (@). # The metadata of user mention.
             "type": "A String", # The type of user mention.
             "user": { # A user in Hangouts Chat. # The user mentioned.
-              "displayName": "A String", # The user's display name.
               "type": "A String", # User type.
+              "domainId": "A String", # Obfuscated domain information.
+              "displayName": "A String", # The user's display name.
               "name": "A String", # Resource name, in the format "users/*".
             },
           },
@@ -805,242 +1080,24 @@
               # annotation corresponds to.
         },
       ],
-      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
-      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
-          # elements such as: formatted texts, buttons, clickable images. Cards are
-          # normally displayed below the plain-text body of the message.
-        { # A card is a UI element that can contain UI widgets such as texts, images.
-          "cardActions": [ # The actions of this card.
-            { # A card action is
-                # the action associated with the card. For an invoice card, a
-                # typical action would be: delete invoice, email invoice or open the
-                # invoice in browser.
-              "actionLabel": "A String", # The label used to be displayed in the action menu item.
-              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
-                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                  "url": "A String", # The URL to open.
-                },
-                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                    # For example, an Apps Script can be invoked to handle the form.
-                  "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                      # clicked/activated.
-                  "parameters": [ # List of action parameters.
-                    { # List of string parameters to supply when the action method is invoked.
-                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                        # snooze next week. You might use action method = snooze(), passing the
-                        # snooze type and snooze time in the list of string parameters.
-                      "value": "A String", # The value of the parameter.
-                      "key": "A String", # The name of the parameter for the action script.
-                    },
-                  ],
-                },
-              },
-            },
-          ],
-          "sections": [ # Sections are separated by a line divider.
-            { # A section contains a collection of widgets that are rendered
-                # (vertically) in the order that they are specified. Across all platforms,
-                # cards have a narrow fixed width, so
-                # there is currently no need for layout properties (e.g. float).
-              "widgets": [ # A section must contain at least 1 widget.
-                { # A widget is a UI element that presents texts, images, etc.
-                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
-                      # fields should be set.
-                    { # A button. Can be a text button or an image button.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                  ],
-                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
-                      # element may also contain some actions such as onclick button.
-                    "contentMultiline": True or False, # If the content should be multiline.
-                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
-                    "topLabel": "A String", # The text of the top label. Formatted text supported.
-                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                    "content": "A String", # The text of the content. Formatted text supported and always required.
-                    "iconUrl": "A String", # The icon specified by a URL.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
-                        # are clickable.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
-                        # corresponding icon image.
-                  },
-                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
-                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height).
-                    "imageUrl": "A String", # The URL of the image.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                  },
-                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
-                    "text": "A String",
-                  },
-                },
-              ],
-              "header": "A String", # The header of the section, text formatted supported.
-            },
-          ],
-          "name": "A String", # Name of the card.
-          "header": { # The header of the card. A header usually contains a title and an image.
-            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
-            "imageUrl": "A String", # The URL of the image in the card header.
-            "subtitle": "A String", # The subtitle of the card header.
-            "title": "A String", # The title must be specified. The header has a fixed height: if both a
-                # title and subtitle is specified, each will take up 1 line. If only the
-                # title is specified, it will take up both lines.
-          },
-        },
-      ],
-      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
-          # user, but any links to images, web pages, videos, etc. included here will
-          # generate preview chips.
-      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
-          # server.
       "sender": { # A user in Hangouts Chat. # The user who created the message.
-        "displayName": "A String", # The user's display name.
         "type": "A String", # User type.
+        "domainId": "A String", # Obfuscated domain information.
+        "displayName": "A String", # The user's display name.
         "name": "A String", # Resource name, in the format "users/*".
       },
     }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="update">update(name, body, updateMask=None, x__xgafv=None)</code>
+    <code class="details" id="update">update(name, body=None, updateMask=None, x__xgafv=None)</code>
   <pre>Updates a message.
 
 Args:
   name: string, Resource name, in the form "spaces/*/messages/*".
 
 Example: spaces/AAAAMpdlehY/messages/UMxbHmzDlr4.UMxbHmzDlr4 (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # A message in Hangouts Chat.
@@ -1058,8 +1115,8 @@
           # Example: spaces/AAAAMpdlehY/threads/UMxbHmzDlr4
     },
     "space": { # A room or DM in Hangouts Chat. # The space the message belongs to.
-      "displayName": "A String", # Output only. The display name (only if the space is a room).
       "type": "A String", # Output only. The type of a space.
+      "displayName": "A String", # Output only. The display name (only if the space is a room).
       "name": "A String", # Resource name of the space, in the form "spaces/*".
           #
           # Example: spaces/AAAAMpdlehYs
@@ -1067,6 +1124,242 @@
     "text": "A String", # Plain-text body of the message.
     "fallbackText": "A String", # A plain-text description of the message's cards, used when the actual cards
         # cannot be displayed (e.g. mobile notifications).
+    "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
+        # server.
+    "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
+    "cards": [ # Rich, formatted and interactive cards that can be used to display UI
+        # elements such as: formatted texts, buttons, clickable images. Cards are
+        # normally displayed below the plain-text body of the message.
+      { # A card is a UI element that can contain UI widgets such as texts, images.
+        "cardActions": [ # The actions of this card.
+          { # A card action is
+              # the action associated with the card. For an invoice card, a
+              # typical action would be: delete invoice, email invoice or open the
+              # invoice in browser.
+            "actionLabel": "A String", # The label used to be displayed in the action menu item.
+            "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
+              "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                  # For example, an Apps Script can be invoked to handle the form.
+                "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                    # form submission. This information is echoed back to the bot as part of
+                    # the card click event. The same method name can be used for several
+                    # elements that trigger a common behavior if desired.
+                "parameters": [ # List of action parameters.
+                  { # List of string parameters to supply when the action method is invoked.
+                      # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                      # snooze next week. You might use action method = snooze(), passing the
+                      # snooze type and snooze time in the list of string parameters.
+                    "key": "A String", # The name of the parameter for the action script.
+                    "value": "A String", # The value of the parameter.
+                  },
+                ],
+              },
+              "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                "url": "A String", # The URL to open.
+              },
+            },
+          },
+        ],
+        "sections": [ # Sections are separated by a line divider.
+          { # A section contains a collection of widgets that are rendered
+              # (vertically) in the order that they are specified. Across all platforms,
+              # cards have a narrow fixed width, so
+              # there is currently no need for layout properties (e.g. float).
+            "widgets": [ # A section must contain at least 1 widget.
+              { # A widget is a UI element that presents texts, images, etc.
+                "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
+                    # fields should be set.
+                  { # A button. Can be a text button or an image button.
+                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                      "iconUrl": "A String", # The icon specified by a URL.
+                      "name": "A String", # The name of this image_button which will be used for accessibility.
+                          # Default value will be provided if developers don't specify.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                          # API.
+                    },
+                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                      "text": "A String", # The text of the button.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                    },
+                  },
+                ],
+                "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
+                    # element may also contain some actions such as onclick button.
+                  "contentMultiline": True or False, # If the content should be multiline.
+                  "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
+                  "topLabel": "A String", # The text of the top label. Formatted text supported.
+                  "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
+                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                      "iconUrl": "A String", # The icon specified by a URL.
+                      "name": "A String", # The name of this image_button which will be used for accessibility.
+                          # Default value will be provided if developers don't specify.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                          # API.
+                    },
+                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                      "text": "A String", # The text of the button.
+                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                            # For example, an Apps Script can be invoked to handle the form.
+                          "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                              # form submission. This information is echoed back to the bot as part of
+                              # the card click event. The same method name can be used for several
+                              # elements that trigger a common behavior if desired.
+                          "parameters": [ # List of action parameters.
+                            { # List of string parameters to supply when the action method is invoked.
+                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                # snooze next week. You might use action method = snooze(), passing the
+                                # snooze type and snooze time in the list of string parameters.
+                              "key": "A String", # The name of the parameter for the action script.
+                              "value": "A String", # The value of the parameter.
+                            },
+                          ],
+                        },
+                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                          "url": "A String", # The URL to open.
+                        },
+                      },
+                    },
+                  },
+                  "content": "A String", # The text of the content. Formatted text supported and always required.
+                  "iconUrl": "A String", # The icon specified by a URL.
+                  "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
+                      # are clickable.
+                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                        # For example, an Apps Script can be invoked to handle the form.
+                      "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                          # form submission. This information is echoed back to the bot as part of
+                          # the card click event. The same method name can be used for several
+                          # elements that trigger a common behavior if desired.
+                      "parameters": [ # List of action parameters.
+                        { # List of string parameters to supply when the action method is invoked.
+                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                            # snooze next week. You might use action method = snooze(), passing the
+                            # snooze type and snooze time in the list of string parameters.
+                          "key": "A String", # The name of the parameter for the action script.
+                          "value": "A String", # The value of the parameter.
+                        },
+                      ],
+                    },
+                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                      "url": "A String", # The URL to open.
+                    },
+                  },
+                  "icon": "A String", # An enum value that will be replaced by the Chat API with the
+                      # corresponding icon image.
+                },
+                "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
+                  "aspectRatio": 3.14, # The aspect ratio of this image (width/height). This field allows clients
+                      # to reserve the right height for the image while waiting for it to load.
+                      # It's not meant to override the native aspect ratio of the image.
+                      # If unset, the server fills it by prefetching the image.
+                  "imageUrl": "A String", # The URL of the image.
+                  "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                        # For example, an Apps Script can be invoked to handle the form.
+                      "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                          # form submission. This information is echoed back to the bot as part of
+                          # the card click event. The same method name can be used for several
+                          # elements that trigger a common behavior if desired.
+                      "parameters": [ # List of action parameters.
+                        { # List of string parameters to supply when the action method is invoked.
+                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                            # snooze next week. You might use action method = snooze(), passing the
+                            # snooze type and snooze time in the list of string parameters.
+                          "key": "A String", # The name of the parameter for the action script.
+                          "value": "A String", # The value of the parameter.
+                        },
+                      ],
+                    },
+                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                      "url": "A String", # The URL to open.
+                    },
+                  },
+                },
+                "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
+                  "text": "A String",
+                },
+              },
+            ],
+            "header": "A String", # The header of the section, text formatted supported.
+          },
+        ],
+        "name": "A String", # Name of the card.
+        "header": { # The header of the card. A header usually contains a title and an image.
+          "imageStyle": "A String", # The image's type (e.g. square border or circular border).
+          "imageUrl": "A String", # The URL of the image in the card header.
+          "subtitle": "A String", # The subtitle of the card header.
+          "title": "A String", # The title must be specified. The header has a fixed height: if both a
+              # title and subtitle is specified, each will take up 1 line. If only the
+              # title is specified, it will take up both lines.
+        },
+      },
+    ],
+    "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
+        # user, but any links to images, web pages, videos, etc. included here will
+        # generate preview chips.
     "annotations": [ # Output only. Annotations associated with the text in this message.
       { # Annotations associated with the plain-text body of the message.
           #
@@ -1095,8 +1388,9 @@
         "userMention": { # Annotation metadata for user mentions (@). # The metadata of user mention.
           "type": "A String", # The type of user mention.
           "user": { # A user in Hangouts Chat. # The user mentioned.
-            "displayName": "A String", # The user's display name.
             "type": "A String", # User type.
+            "domainId": "A String", # Obfuscated domain information.
+            "displayName": "A String", # The user's display name.
             "name": "A String", # Resource name, in the format "users/*".
           },
         },
@@ -1107,235 +1401,20 @@
             # annotation corresponds to.
       },
     ],
-    "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
-    "cards": [ # Rich, formatted and interactive cards that can be used to display UI
-        # elements such as: formatted texts, buttons, clickable images. Cards are
-        # normally displayed below the plain-text body of the message.
-      { # A card is a UI element that can contain UI widgets such as texts, images.
-        "cardActions": [ # The actions of this card.
-          { # A card action is
-              # the action associated with the card. For an invoice card, a
-              # typical action would be: delete invoice, email invoice or open the
-              # invoice in browser.
-            "actionLabel": "A String", # The label used to be displayed in the action menu item.
-            "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
-              "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                "url": "A String", # The URL to open.
-              },
-              "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                  # For example, an Apps Script can be invoked to handle the form.
-                "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                    # clicked/activated.
-                "parameters": [ # List of action parameters.
-                  { # List of string parameters to supply when the action method is invoked.
-                      # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                      # snooze next week. You might use action method = snooze(), passing the
-                      # snooze type and snooze time in the list of string parameters.
-                    "value": "A String", # The value of the parameter.
-                    "key": "A String", # The name of the parameter for the action script.
-                  },
-                ],
-              },
-            },
-          },
-        ],
-        "sections": [ # Sections are separated by a line divider.
-          { # A section contains a collection of widgets that are rendered
-              # (vertically) in the order that they are specified. Across all platforms,
-              # cards have a narrow fixed width, so
-              # there is currently no need for layout properties (e.g. float).
-            "widgets": [ # A section must contain at least 1 widget.
-              { # A widget is a UI element that presents texts, images, etc.
-                "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
-                    # fields should be set.
-                  { # A button. Can be a text button or an image button.
-                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                      "iconUrl": "A String", # The icon specified by a URL.
-                      "name": "A String", # The name of this image_button which will be used for accessibility.
-                          # Default value will be provided if developers don't specify.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                          # API.
-                    },
-                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                      "text": "A String", # The text of the button.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                    },
-                  },
-                ],
-                "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
-                    # element may also contain some actions such as onclick button.
-                  "contentMultiline": True or False, # If the content should be multiline.
-                  "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
-                  "topLabel": "A String", # The text of the top label. Formatted text supported.
-                  "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
-                    "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                      "iconUrl": "A String", # The icon specified by a URL.
-                      "name": "A String", # The name of this image_button which will be used for accessibility.
-                          # Default value will be provided if developers don't specify.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                      "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                          # API.
-                    },
-                    "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                      "text": "A String", # The text of the button.
-                      "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                        "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                          "url": "A String", # The URL to open.
-                        },
-                        "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                            # For example, an Apps Script can be invoked to handle the form.
-                          "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                              # clicked/activated.
-                          "parameters": [ # List of action parameters.
-                            { # List of string parameters to supply when the action method is invoked.
-                                # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                # snooze next week. You might use action method = snooze(), passing the
-                                # snooze type and snooze time in the list of string parameters.
-                              "value": "A String", # The value of the parameter.
-                              "key": "A String", # The name of the parameter for the action script.
-                            },
-                          ],
-                        },
-                      },
-                    },
-                  },
-                  "content": "A String", # The text of the content. Formatted text supported and always required.
-                  "iconUrl": "A String", # The icon specified by a URL.
-                  "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
-                      # are clickable.
-                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                      "url": "A String", # The URL to open.
-                    },
-                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                        # For example, an Apps Script can be invoked to handle the form.
-                      "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                          # clicked/activated.
-                      "parameters": [ # List of action parameters.
-                        { # List of string parameters to supply when the action method is invoked.
-                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                            # snooze next week. You might use action method = snooze(), passing the
-                            # snooze type and snooze time in the list of string parameters.
-                          "value": "A String", # The value of the parameter.
-                          "key": "A String", # The name of the parameter for the action script.
-                        },
-                      ],
-                    },
-                  },
-                  "icon": "A String", # An enum value that will be replaced by the Chat API with the
-                      # corresponding icon image.
-                },
-                "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
-                  "aspectRatio": 3.14, # The aspect ratio of this image (width/height).
-                  "imageUrl": "A String", # The URL of the image.
-                  "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                    "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                      "url": "A String", # The URL to open.
-                    },
-                    "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                        # For example, an Apps Script can be invoked to handle the form.
-                      "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                          # clicked/activated.
-                      "parameters": [ # List of action parameters.
-                        { # List of string parameters to supply when the action method is invoked.
-                            # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                            # snooze next week. You might use action method = snooze(), passing the
-                            # snooze type and snooze time in the list of string parameters.
-                          "value": "A String", # The value of the parameter.
-                          "key": "A String", # The name of the parameter for the action script.
-                        },
-                      ],
-                    },
-                  },
-                },
-                "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
-                  "text": "A String",
-                },
-              },
-            ],
-            "header": "A String", # The header of the section, text formatted supported.
-          },
-        ],
-        "name": "A String", # Name of the card.
-        "header": { # The header of the card. A header usually contains a title and an image.
-          "imageStyle": "A String", # The image's type (e.g. square border or circular border).
-          "imageUrl": "A String", # The URL of the image in the card header.
-          "subtitle": "A String", # The subtitle of the card header.
-          "title": "A String", # The title must be specified. The header has a fixed height: if both a
-              # title and subtitle is specified, each will take up 1 line. If only the
-              # title is specified, it will take up both lines.
-        },
-      },
-    ],
-    "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
-        # user, but any links to images, web pages, videos, etc. included here will
-        # generate preview chips.
-    "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
-        # server.
     "sender": { # A user in Hangouts Chat. # The user who created the message.
-      "displayName": "A String", # The user's display name.
       "type": "A String", # User type.
+      "domainId": "A String", # Obfuscated domain information.
+      "displayName": "A String", # The user's display name.
       "name": "A String", # Resource name, in the format "users/*".
     },
   }
 
-  updateMask: string, Required. The field paths to be updated.
+  updateMask: string, Required. The field paths to be updated, comma separated if there are
+multiple.
 
-Currently supported field paths: "text", "cards".
+Currently supported field paths:
+* text
+* cards
   x__xgafv: string, V1 error format.
     Allowed values
       1 - v1 error format
@@ -1359,8 +1438,8 @@
             # Example: spaces/AAAAMpdlehY/threads/UMxbHmzDlr4
       },
       "space": { # A room or DM in Hangouts Chat. # The space the message belongs to.
-        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "type": "A String", # Output only. The type of a space.
+        "displayName": "A String", # Output only. The display name (only if the space is a room).
         "name": "A String", # Resource name of the space, in the form "spaces/*".
             #
             # Example: spaces/AAAAMpdlehYs
@@ -1368,6 +1447,242 @@
       "text": "A String", # Plain-text body of the message.
       "fallbackText": "A String", # A plain-text description of the message's cards, used when the actual cards
           # cannot be displayed (e.g. mobile notifications).
+      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
+          # server.
+      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
+      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
+          # elements such as: formatted texts, buttons, clickable images. Cards are
+          # normally displayed below the plain-text body of the message.
+        { # A card is a UI element that can contain UI widgets such as texts, images.
+          "cardActions": [ # The actions of this card.
+            { # A card action is
+                # the action associated with the card. For an invoice card, a
+                # typical action would be: delete invoice, email invoice or open the
+                # invoice in browser.
+              "actionLabel": "A String", # The label used to be displayed in the action menu item.
+              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
+                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                    # For example, an Apps Script can be invoked to handle the form.
+                  "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                      # form submission. This information is echoed back to the bot as part of
+                      # the card click event. The same method name can be used for several
+                      # elements that trigger a common behavior if desired.
+                  "parameters": [ # List of action parameters.
+                    { # List of string parameters to supply when the action method is invoked.
+                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                        # snooze next week. You might use action method = snooze(), passing the
+                        # snooze type and snooze time in the list of string parameters.
+                      "key": "A String", # The name of the parameter for the action script.
+                      "value": "A String", # The value of the parameter.
+                    },
+                  ],
+                },
+                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                  "url": "A String", # The URL to open.
+                },
+              },
+            },
+          ],
+          "sections": [ # Sections are separated by a line divider.
+            { # A section contains a collection of widgets that are rendered
+                # (vertically) in the order that they are specified. Across all platforms,
+                # cards have a narrow fixed width, so
+                # there is currently no need for layout properties (e.g. float).
+              "widgets": [ # A section must contain at least 1 widget.
+                { # A widget is a UI element that presents texts, images, etc.
+                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
+                      # fields should be set.
+                    { # A button. Can be a text button or an image button.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                  ],
+                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
+                      # element may also contain some actions such as onclick button.
+                    "contentMultiline": True or False, # If the content should be multiline.
+                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
+                    "topLabel": "A String", # The text of the top label. Formatted text supported.
+                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
+                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
+                        "iconUrl": "A String", # The icon specified by a URL.
+                        "name": "A String", # The name of this image_button which will be used for accessibility.
+                            # Default value will be provided if developers don't specify.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
+                            # API.
+                      },
+                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
+                        "text": "A String", # The text of the button.
+                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
+                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                              # For example, an Apps Script can be invoked to handle the form.
+                            "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                                # form submission. This information is echoed back to the bot as part of
+                                # the card click event. The same method name can be used for several
+                                # elements that trigger a common behavior if desired.
+                            "parameters": [ # List of action parameters.
+                              { # List of string parameters to supply when the action method is invoked.
+                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                                  # snooze next week. You might use action method = snooze(), passing the
+                                  # snooze type and snooze time in the list of string parameters.
+                                "key": "A String", # The name of the parameter for the action script.
+                                "value": "A String", # The value of the parameter.
+                              },
+                            ],
+                          },
+                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                            "url": "A String", # The URL to open.
+                          },
+                        },
+                      },
+                    },
+                    "content": "A String", # The text of the content. Formatted text supported and always required.
+                    "iconUrl": "A String", # The icon specified by a URL.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
+                        # are clickable.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
+                        # corresponding icon image.
+                  },
+                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
+                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height). This field allows clients
+                        # to reserve the right height for the image while waiting for it to load.
+                        # It's not meant to override the native aspect ratio of the image.
+                        # If unset, the server fills it by prefetching the image.
+                    "imageUrl": "A String", # The URL of the image.
+                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
+                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
+                          # For example, an Apps Script can be invoked to handle the form.
+                        "actionMethodName": "A String", # The method name is used to identify which part of the form triggered the
+                            # form submission. This information is echoed back to the bot as part of
+                            # the card click event. The same method name can be used for several
+                            # elements that trigger a common behavior if desired.
+                        "parameters": [ # List of action parameters.
+                          { # List of string parameters to supply when the action method is invoked.
+                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
+                              # snooze next week. You might use action method = snooze(), passing the
+                              # snooze type and snooze time in the list of string parameters.
+                            "key": "A String", # The name of the parameter for the action script.
+                            "value": "A String", # The value of the parameter.
+                          },
+                        ],
+                      },
+                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
+                        "url": "A String", # The URL to open.
+                      },
+                    },
+                  },
+                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
+                    "text": "A String",
+                  },
+                },
+              ],
+              "header": "A String", # The header of the section, text formatted supported.
+            },
+          ],
+          "name": "A String", # Name of the card.
+          "header": { # The header of the card. A header usually contains a title and an image.
+            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
+            "imageUrl": "A String", # The URL of the image in the card header.
+            "subtitle": "A String", # The subtitle of the card header.
+            "title": "A String", # The title must be specified. The header has a fixed height: if both a
+                # title and subtitle is specified, each will take up 1 line. If only the
+                # title is specified, it will take up both lines.
+          },
+        },
+      ],
+      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
+          # user, but any links to images, web pages, videos, etc. included here will
+          # generate preview chips.
       "annotations": [ # Output only. Annotations associated with the text in this message.
         { # Annotations associated with the plain-text body of the message.
             #
@@ -1396,8 +1711,9 @@
           "userMention": { # Annotation metadata for user mentions (@). # The metadata of user mention.
             "type": "A String", # The type of user mention.
             "user": { # A user in Hangouts Chat. # The user mentioned.
-              "displayName": "A String", # The user's display name.
               "type": "A String", # User type.
+              "domainId": "A String", # Obfuscated domain information.
+              "displayName": "A String", # The user's display name.
               "name": "A String", # Resource name, in the format "users/*".
             },
           },
@@ -1408,228 +1724,10 @@
               # annotation corresponds to.
         },
       ],
-      "argumentText": "A String", # Plain-text body of the message with all bot mentions stripped out.
-      "cards": [ # Rich, formatted and interactive cards that can be used to display UI
-          # elements such as: formatted texts, buttons, clickable images. Cards are
-          # normally displayed below the plain-text body of the message.
-        { # A card is a UI element that can contain UI widgets such as texts, images.
-          "cardActions": [ # The actions of this card.
-            { # A card action is
-                # the action associated with the card. For an invoice card, a
-                # typical action would be: delete invoice, email invoice or open the
-                # invoice in browser.
-              "actionLabel": "A String", # The label used to be displayed in the action menu item.
-              "onClick": { # An onclick action (e.g. open a link). # The onclick action for this action item.
-                "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                  "url": "A String", # The URL to open.
-                },
-                "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                    # For example, an Apps Script can be invoked to handle the form.
-                  "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                      # clicked/activated.
-                  "parameters": [ # List of action parameters.
-                    { # List of string parameters to supply when the action method is invoked.
-                        # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                        # snooze next week. You might use action method = snooze(), passing the
-                        # snooze type and snooze time in the list of string parameters.
-                      "value": "A String", # The value of the parameter.
-                      "key": "A String", # The name of the parameter for the action script.
-                    },
-                  ],
-                },
-              },
-            },
-          ],
-          "sections": [ # Sections are separated by a line divider.
-            { # A section contains a collection of widgets that are rendered
-                # (vertically) in the order that they are specified. Across all platforms,
-                # cards have a narrow fixed width, so
-                # there is currently no need for layout properties (e.g. float).
-              "widgets": [ # A section must contain at least 1 widget.
-                { # A widget is a UI element that presents texts, images, etc.
-                  "buttons": [ # A list of buttons. Buttons is also oneof data and only one of these
-                      # fields should be set.
-                    { # A button. Can be a text button or an image button.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                  ],
-                  "keyValue": { # A UI element contains a key (label) and a value (content). And this # Display a key value item in this widget.
-                      # element may also contain some actions such as onclick button.
-                    "contentMultiline": True or False, # If the content should be multiline.
-                    "bottomLabel": "A String", # The text of the bottom label. Formatted text supported.
-                    "topLabel": "A String", # The text of the top label. Formatted text supported.
-                    "button": { # A button. Can be a text button or an image button. # A button that can be clicked to trigger an action.
-                      "imageButton": { # An image button with an onclick action. # A button with image and onclick action.
-                        "iconUrl": "A String", # The icon specified by a URL.
-                        "name": "A String", # The name of this image_button which will be used for accessibility.
-                            # Default value will be provided if developers don't specify.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                        "icon": "A String", # The icon specified by an enum that indices to an icon provided by Chat
-                            # API.
-                      },
-                      "textButton": { # A button with text and onclick action. # A button with text and onclick action.
-                        "text": "A String", # The text of the button.
-                        "onClick": { # An onclick action (e.g. open a link). # The onclick action of the button.
-                          "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                            "url": "A String", # The URL to open.
-                          },
-                          "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                              # For example, an Apps Script can be invoked to handle the form.
-                            "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                                # clicked/activated.
-                            "parameters": [ # List of action parameters.
-                              { # List of string parameters to supply when the action method is invoked.
-                                  # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                                  # snooze next week. You might use action method = snooze(), passing the
-                                  # snooze type and snooze time in the list of string parameters.
-                                "value": "A String", # The value of the parameter.
-                                "key": "A String", # The name of the parameter for the action script.
-                              },
-                            ],
-                          },
-                        },
-                      },
-                    },
-                    "content": "A String", # The text of the content. Formatted text supported and always required.
-                    "iconUrl": "A String", # The icon specified by a URL.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action. Only the top label, bottom label and content region
-                        # are clickable.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                    "icon": "A String", # An enum value that will be replaced by the Chat API with the
-                        # corresponding icon image.
-                  },
-                  "image": { # An image that is specified by a URL and can have an onclick action. # Display an image in this widget.
-                    "aspectRatio": 3.14, # The aspect ratio of this image (width/height).
-                    "imageUrl": "A String", # The URL of the image.
-                    "onClick": { # An onclick action (e.g. open a link). # The onclick action.
-                      "openLink": { # A link that opens a new window. # This onclick triggers an open link action if specified.
-                        "url": "A String", # The URL to open.
-                      },
-                      "action": { # A form action describes the behavior when the form is submitted. # A form action will be trigger by this onclick if specified.
-                          # For example, an Apps Script can be invoked to handle the form.
-                        "actionMethodName": "A String", # Apps Script function to invoke when the containing element is
-                            # clicked/activated.
-                        "parameters": [ # List of action parameters.
-                          { # List of string parameters to supply when the action method is invoked.
-                              # For example, consider three snooze buttons: snooze now, snooze 1 day,
-                              # snooze next week. You might use action method = snooze(), passing the
-                              # snooze type and snooze time in the list of string parameters.
-                            "value": "A String", # The value of the parameter.
-                            "key": "A String", # The name of the parameter for the action script.
-                          },
-                        ],
-                      },
-                    },
-                  },
-                  "textParagraph": { # A paragraph of text. Formatted text supported. # Display a text paragraph in this widget.
-                    "text": "A String",
-                  },
-                },
-              ],
-              "header": "A String", # The header of the section, text formatted supported.
-            },
-          ],
-          "name": "A String", # Name of the card.
-          "header": { # The header of the card. A header usually contains a title and an image.
-            "imageStyle": "A String", # The image's type (e.g. square border or circular border).
-            "imageUrl": "A String", # The URL of the image in the card header.
-            "subtitle": "A String", # The subtitle of the card header.
-            "title": "A String", # The title must be specified. The header has a fixed height: if both a
-                # title and subtitle is specified, each will take up 1 line. If only the
-                # title is specified, it will take up both lines.
-          },
-        },
-      ],
-      "previewText": "A String", # Text for generating preview chips. This text will not be displayed to the
-          # user, but any links to images, web pages, videos, etc. included here will
-          # generate preview chips.
-      "createTime": "A String", # Output only. The time at which the message was created in Hangouts Chat
-          # server.
       "sender": { # A user in Hangouts Chat. # The user who created the message.
-        "displayName": "A String", # The user's display name.
         "type": "A String", # User type.
+        "domainId": "A String", # Obfuscated domain information.
+        "displayName": "A String", # The user's display name.
         "name": "A String", # Resource name, in the format "users/*".
       },
     }</pre>