Update docs (#291)

diff --git a/docs/dyn/logging_v2beta1.projects.sinks.html b/docs/dyn/logging_v2beta1.projects.sinks.html
index 7b94b4f..2ff8f0e 100644
--- a/docs/dyn/logging_v2beta1.projects.sinks.html
+++ b/docs/dyn/logging_v2beta1.projects.sinks.html
@@ -72,111 +72,265 @@
 
 </style>
 
-<h1><a href="logging_v2beta1.html">Google Cloud Logging API</a> . <a href="logging_v2beta1.projects.html">projects</a> . <a href="logging_v2beta1.projects.sinks.html">sinks</a></h1>
+<h1><a href="logging_v2beta1.html">Stackdriver Logging API</a> . <a href="logging_v2beta1.projects.html">projects</a> . <a href="logging_v2beta1.projects.sinks.html">sinks</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#create">create(projectName, body, x__xgafv=None)</a></code></p>
+  <code><a href="#create">create(parent=None, body, x__xgafv=None)</a></code></p>
 <p class="firstline">Creates a sink.</p>
 <p class="toc_element">
-  <code><a href="#delete">delete(sinkName, x__xgafv=None)</a></code></p>
+  <code><a href="#delete">delete(sinkName=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Deletes a sink.</p>
 <p class="toc_element">
-  <code><a href="#get">get(sinkName, x__xgafv=None)</a></code></p>
+  <code><a href="#get">get(sinkName=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Gets a sink.</p>
 <p class="toc_element">
-  <code><a href="#list">list(projectName, pageSize=None, pageToken=None, x__xgafv=None)</a></code></p>
+  <code><a href="#list">list(parent=None, pageToken=None, x__xgafv=None, pageSize=None)</a></code></p>
 <p class="firstline">Lists sinks.</p>
 <p class="toc_element">
   <code><a href="#list_next">list_next(previous_request, previous_response)</a></code></p>
 <p class="firstline">Retrieves the next page of results.</p>
 <p class="toc_element">
-  <code><a href="#update">update(sinkName, body, x__xgafv=None)</a></code></p>
-<p class="firstline">Creates or updates a sink.</p>
+  <code><a href="#update">update(sinkName=None, body, x__xgafv=None)</a></code></p>
+<p class="firstline">Updates or creates a sink.</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="create">create(projectName, body, x__xgafv=None)</code>
+    <code class="details" id="create">create(parent=None, body, x__xgafv=None)</code>
   <pre>Creates a sink.
 
 Args:
-  projectName: string, The resource name of the project in which to create the sink. Example: `"projects/my-project-id"`. The new sink must be provided in the request. (required)
+  parent: string, Required. The resource in which to create the sink.
+Example: `"projects/my-project-id"`.
+The new sink must be provided in the request. (required)
   body: object, The request body. (required)
     The object takes the form of:
 
-{ # Describes a sink used to export log entries outside Cloud Logging.
-    "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-    "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-    "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-    "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+{ # Describes a sink used to export log entries outside Stackdriver Logging.
+    "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+        # Only log entries matching the filter are exported. The filter
+        # must be consistent with the log entry format specified by the
+        # `outputVersionFormat` parameter, regardless of the format of the
+        # log entry that was originally written to Stackdriver Logging.
+        # Example filter (V2 format):
+        # 
+        #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+    "destination": "A String", # Required. The export destination. See
+        # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+        # Examples:
+        # 
+        #     "storage.googleapis.com/my-gcs-bucket"
+        #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+        #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+    "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+        # access.  This may be a service account or a group.
+        # Examples (Do not assume these specific values):
+        #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+        #    "group:cloud-logs@google.com"
+        # 
+        #   For GCS destinations, the role "roles/owner" is required on the bucket
+        #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+        #     required on the topic
+        #   For BigQuery, the role "roles/editor" is required on the dataset
+    "name": "A String", # Required. The client-assigned sink identifier, unique within the
+        # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+        # limited to 1000 characters and can include only the following characters:
+        # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+        # of the name is 100 characters.
+    "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+        # entries.  This version does not have to correspond to the version of the
+        # log entry that was written to Stackdriver Logging. If omitted, the
+        # v2 format is used.
   }
 
   x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
 
-    { # Describes a sink used to export log entries outside Cloud Logging.
-      "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-      "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-      "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-      "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+    { # Describes a sink used to export log entries outside Stackdriver Logging.
+      "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+          # Only log entries matching the filter are exported. The filter
+          # must be consistent with the log entry format specified by the
+          # `outputVersionFormat` parameter, regardless of the format of the
+          # log entry that was originally written to Stackdriver Logging.
+          # Example filter (V2 format):
+          #
+          #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+      "destination": "A String", # Required. The export destination. See
+          # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+          # Examples:
+          #
+          #     "storage.googleapis.com/my-gcs-bucket"
+          #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+          #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+      "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+          # access.  This may be a service account or a group.
+          # Examples (Do not assume these specific values):
+          #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+          #    "group:cloud-logs@google.com"
+          #
+          #   For GCS destinations, the role "roles/owner" is required on the bucket
+          #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+          #     required on the topic
+          #   For BigQuery, the role "roles/editor" is required on the dataset
+      "name": "A String", # Required. The client-assigned sink identifier, unique within the
+          # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+          # limited to 1000 characters and can include only the following characters:
+          # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+          # of the name is 100 characters.
+      "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+          # entries.  This version does not have to correspond to the version of the
+          # log entry that was written to Stackdriver Logging. If omitted, the
+          # v2 format is used.
     }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="delete">delete(sinkName, x__xgafv=None)</code>
+    <code class="details" id="delete">delete(sinkName=None, x__xgafv=None)</code>
   <pre>Deletes a sink.
 
 Args:
-  sinkName: string, The resource name of the sink to delete. Example: `"projects/my-project-id/sinks/my-sink-id"`. (required)
+  sinkName: string, Required. The resource name of the sink to delete, including the parent
+resource and the sink identifier.  Example:
+`"projects/my-project-id/sinks/my-sink-id"`.  It is an error if the sink
+does not exist. (required)
   x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
 
-    { # A generic empty message that you can re-use to avoid defining duplicated empty messages in your APIs. A typical example is to use it as the request or the response type of an API method. For instance: service Foo { rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty); } The JSON representation for `Empty` is empty JSON object `{}`.
+    { # A generic empty message that you can re-use to avoid defining duplicated
+      # empty messages in your APIs. A typical example is to use it as the request
+      # or the response type of an API method. For instance:
+      #
+      #     service Foo {
+      #       rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
+      #     }
+      #
+      # The JSON representation for `Empty` is empty JSON object `{}`.
   }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="get">get(sinkName, x__xgafv=None)</code>
+    <code class="details" id="get">get(sinkName=None, x__xgafv=None)</code>
   <pre>Gets a sink.
 
 Args:
-  sinkName: string, The resource name of the sink to return. Example: `"projects/my-project-id/sinks/my-sink-id"`. (required)
+  sinkName: string, Required. The resource name of the sink to return.
+Example: `"projects/my-project-id/sinks/my-sink-id"`. (required)
   x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
 
-    { # Describes a sink used to export log entries outside Cloud Logging.
-      "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-      "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-      "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-      "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+    { # Describes a sink used to export log entries outside Stackdriver Logging.
+      "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+          # Only log entries matching the filter are exported. The filter
+          # must be consistent with the log entry format specified by the
+          # `outputVersionFormat` parameter, regardless of the format of the
+          # log entry that was originally written to Stackdriver Logging.
+          # Example filter (V2 format):
+          #
+          #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+      "destination": "A String", # Required. The export destination. See
+          # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+          # Examples:
+          #
+          #     "storage.googleapis.com/my-gcs-bucket"
+          #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+          #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+      "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+          # access.  This may be a service account or a group.
+          # Examples (Do not assume these specific values):
+          #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+          #    "group:cloud-logs@google.com"
+          #
+          #   For GCS destinations, the role "roles/owner" is required on the bucket
+          #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+          #     required on the topic
+          #   For BigQuery, the role "roles/editor" is required on the dataset
+      "name": "A String", # Required. The client-assigned sink identifier, unique within the
+          # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+          # limited to 1000 characters and can include only the following characters:
+          # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+          # of the name is 100 characters.
+      "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+          # entries.  This version does not have to correspond to the version of the
+          # log entry that was written to Stackdriver Logging. If omitted, the
+          # v2 format is used.
     }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="list">list(projectName, pageSize=None, pageToken=None, x__xgafv=None)</code>
+    <code class="details" id="list">list(parent=None, pageToken=None, x__xgafv=None, pageSize=None)</code>
   <pre>Lists sinks.
 
 Args:
-  projectName: string, Required. The resource name of the project containing the sinks. Example: `"projects/my-logging-project"`. (required)
-  pageSize: integer, Optional. The maximum number of results to return from this request. You must check for presence of `nextPageToken` to determine if additional results are available, which you can retrieve by passing the `nextPageToken` value as the `pageToken` parameter in the next request.
-  pageToken: string, Optional. If the `pageToken` parameter is supplied, then the next page of results is retrieved. The `pageToken` parameter must be set to the value of the `nextPageToken` from the previous response. The value of `projectName` must be the same as in the previous request.
+  parent: string, Required. The cloud resource containing the sinks.
+Example: `"projects/my-logging-project"`. (required)
+  pageToken: string, Optional. If present, then retrieve the next batch of results from the
+preceding call to this method.  `pageToken` must be the value of
+`nextPageToken` from the previous response.  The values of other method
+parameters should be identical to those in the previous call.
   x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
+  pageSize: integer, Optional. The maximum number of results to return from this request.
+Non-positive values are ignored.  The presence of `nextPageToken` in the
+response indicates that more results might be available.
 
 Returns:
   An object of the form:
 
     { # Result returned from `ListSinks`.
-    "nextPageToken": "A String", # If there are more results than were returned, then `nextPageToken` is included in the response. To get the next set of results, call this method again using the value of `nextPageToken` as `pageToken`.
+    "nextPageToken": "A String", # If there might be more results than appear in this response, then
+        # `nextPageToken` is included.  To get the next set of results, call the same
+        # method again using the value of `nextPageToken` as `pageToken`.
     "sinks": [ # A list of sinks.
-      { # Describes a sink used to export log entries outside Cloud Logging.
-          "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-          "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-          "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-          "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+      { # Describes a sink used to export log entries outside Stackdriver Logging.
+          "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+              # Only log entries matching the filter are exported. The filter
+              # must be consistent with the log entry format specified by the
+              # `outputVersionFormat` parameter, regardless of the format of the
+              # log entry that was originally written to Stackdriver Logging.
+              # Example filter (V2 format):
+              #
+              #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+          "destination": "A String", # Required. The export destination. See
+              # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+              # Examples:
+              #
+              #     "storage.googleapis.com/my-gcs-bucket"
+              #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+              #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+          "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+              # access.  This may be a service account or a group.
+              # Examples (Do not assume these specific values):
+              #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+              #    "group:cloud-logs@google.com"
+              #
+              #   For GCS destinations, the role "roles/owner" is required on the bucket
+              #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+              #     required on the topic
+              #   For BigQuery, the role "roles/editor" is required on the dataset
+          "name": "A String", # Required. The client-assigned sink identifier, unique within the
+              # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+              # limited to 1000 characters and can include only the following characters:
+              # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+              # of the name is 100 characters.
+          "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+              # entries.  This version does not have to correspond to the version of the
+              # log entry that was written to Stackdriver Logging. If omitted, the
+              # v2 format is used.
         },
     ],
   }</pre>
@@ -197,31 +351,96 @@
 </div>
 
 <div class="method">
-    <code class="details" id="update">update(sinkName, body, x__xgafv=None)</code>
-  <pre>Creates or updates a sink.
+    <code class="details" id="update">update(sinkName=None, body, x__xgafv=None)</code>
+  <pre>Updates or creates a sink.
 
 Args:
-  sinkName: string, The resource name of the sink to update. Example: `"projects/my-project-id/sinks/my-sink-id"`. The updated sink must be provided in the request and have the same name that is specified in `sinkName`. If the sink does not exist, it is created. (required)
+  sinkName: string, Required. The resource name of the sink to update, including the parent
+resource and the sink identifier.  If the sink does not exist, this method
+creates the sink.  Example: `"projects/my-project-id/sinks/my-sink-id"`. (required)
   body: object, The request body. (required)
     The object takes the form of:
 
-{ # Describes a sink used to export log entries outside Cloud Logging.
-    "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-    "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-    "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-    "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+{ # Describes a sink used to export log entries outside Stackdriver Logging.
+    "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+        # Only log entries matching the filter are exported. The filter
+        # must be consistent with the log entry format specified by the
+        # `outputVersionFormat` parameter, regardless of the format of the
+        # log entry that was originally written to Stackdriver Logging.
+        # Example filter (V2 format):
+        # 
+        #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+    "destination": "A String", # Required. The export destination. See
+        # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+        # Examples:
+        # 
+        #     "storage.googleapis.com/my-gcs-bucket"
+        #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+        #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+    "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+        # access.  This may be a service account or a group.
+        # Examples (Do not assume these specific values):
+        #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+        #    "group:cloud-logs@google.com"
+        # 
+        #   For GCS destinations, the role "roles/owner" is required on the bucket
+        #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+        #     required on the topic
+        #   For BigQuery, the role "roles/editor" is required on the dataset
+    "name": "A String", # Required. The client-assigned sink identifier, unique within the
+        # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+        # limited to 1000 characters and can include only the following characters:
+        # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+        # of the name is 100 characters.
+    "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+        # entries.  This version does not have to correspond to the version of the
+        # log entry that was written to Stackdriver Logging. If omitted, the
+        # v2 format is used.
   }
 
   x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
 
-    { # Describes a sink used to export log entries outside Cloud Logging.
-      "filter": "A String", # An [advanced logs filter](/logging/docs/view/advanced_filters). Only log entries matching that filter are exported. The filter must be consistent with the log entry format specified by the `outputVersionFormat` parameter, regardless of the format of the log entry that was originally written to Cloud Logging. Example (V2 format): `"logName=projects/my-projectid/logs/syslog AND severity>=ERROR"`.
-      "destination": "A String", # The export destination. See [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs). Examples: `"storage.googleapis.com/a-bucket"`, `"bigquery.googleapis.com/projects/a-project-id/datasets/a-dataset"`.
-      "name": "A String", # Required. The client-assigned sink identifier. Example: `"my-severe-errors-to-pubsub"`. Sink identifiers are limited to 1000 characters and can include only the following characters: `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.
-      "outputVersionFormat": "A String", # The log entry version to use for this sink's exported log entries. This version does not have to correspond to the version of the log entry when it was written to Cloud Logging.
+    { # Describes a sink used to export log entries outside Stackdriver Logging.
+      "filter": "A String", # Optional. An [advanced logs filter](/logging/docs/view/advanced_filters).
+          # Only log entries matching the filter are exported. The filter
+          # must be consistent with the log entry format specified by the
+          # `outputVersionFormat` parameter, regardless of the format of the
+          # log entry that was originally written to Stackdriver Logging.
+          # Example filter (V2 format):
+          #
+          #     logName=projects/my-projectid/logs/syslog AND severity>=ERROR
+      "destination": "A String", # Required. The export destination. See
+          # [Exporting Logs With Sinks](/logging/docs/api/tasks/exporting-logs).
+          # Examples:
+          #
+          #     "storage.googleapis.com/my-gcs-bucket"
+          #     "bigquery.googleapis.com/projects/my-project-id/datasets/my-dataset"
+          #     "pubsub.googleapis.com/projects/my-project/topics/my-topic"
+      "writerIdentity": "A String", # Output only. The iam identity to which the destination needs to grant write
+          # access.  This may be a service account or a group.
+          # Examples (Do not assume these specific values):
+          #    "serviceAccount:cloud-logs@system.gserviceaccount.com"
+          #    "group:cloud-logs@google.com"
+          #
+          #   For GCS destinations, the role "roles/owner" is required on the bucket
+          #   For Cloud Pubsub destinations, the role "roles/pubsub.publisher" is
+          #     required on the topic
+          #   For BigQuery, the role "roles/editor" is required on the dataset
+      "name": "A String", # Required. The client-assigned sink identifier, unique within the
+          # project. Example: `"my-syslog-errors-to-pubsub"`.  Sink identifiers are
+          # limited to 1000 characters and can include only the following characters:
+          # `A-Z`, `a-z`, `0-9`, and the special characters `_-.`.  The maximum length
+          # of the name is 100 characters.
+      "outputVersionFormat": "A String", # Optional. The log entry version to use for this sink's exported log
+          # entries.  This version does not have to correspond to the version of the
+          # log entry that was written to Stackdriver Logging. If omitted, the
+          # v2 format is used.
     }</pre>
 </div>