Import platform/external/icing

source_repository_url: "user/adorokhine/icing-search-ag"
source_branch: "staging"
source_tip_commit: "67ceaa1d6b6d7da5fa5ed3512ada340c2060250e"
target_repository_name: "platform/external/icing"
Bug: 145010258
Change-Id: I948c0d7979563d688ba08c13614ab6a54ad3a7ff
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/.gitignore
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..654a071
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,28 @@
+# How to Contribute
+
+We'd love to accept your patches and contributions to this project. There are
+just a few small guidelines you need to follow.
+
+## Contributor License Agreement
+
+Contributions to this project must be accompanied by a Contributor License
+Agreement. You (or your employer) retain the copyright to your contribution;
+this simply gives us permission to use and redistribute your contributions as
+part of the project. Head over to <https://cla.developers.google.com/> to see
+your current agreements on file or to sign a new one.
+
+You generally only need to submit a CLA once, so if you've already submitted one
+(even if it was for a different project), you probably don't need to do it
+again.
+
+## Code reviews
+
+All submissions, including submissions by project members, require review. We
+use GitHub pull requests for this purpose. Consult
+[GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
+information on using pull requests.
+
+## Community Guidelines
+
+This project follows [Google's Open Source Community
+Guidelines](https://opensource.google/conduct/).
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,202 @@
+
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+   6. Trademarks. This License does not grant permission to use the trade
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diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..fc01d33
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,18 @@
+name: "Icing Search Library"
+description:
+    "Icing is a fast, embedded, mobile-friendly full-text-search library "
+    "written in C++."
+
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://github.com/google/icing-search"
+  }
+  url {
+    type: GIT
+    value: "https://github.com/google/icing-search.git"
+  }
+  version: "6ac7095a212a01dd0d25e39843bb593486625370"
+  last_upgrade_date { year: 2019 month: 10 day: 31 }
+  license_type: NOTICE
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/NOTICE b/NOTICE
new file mode 120000
index 0000000..7a694c9
--- /dev/null
+++ b/NOTICE
@@ -0,0 +1 @@
+LICENSE
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..8f6df57
--- /dev/null
+++ b/README.md
@@ -0,0 +1,5 @@
+# Icing Search Library
+
+Icing is a fast, embedded, mobile-friendly full-text-search library written in C++.
+
+This is not an officially supported Google product.
diff --git a/icing/proto/document.proto b/icing/proto/document.proto
new file mode 100644
index 0000000..64c2e2b
--- /dev/null
+++ b/icing/proto/document.proto
@@ -0,0 +1,59 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+// Defines a unit of data understood by the IcingSearchEngine.
+// Next tag: 6
+message DocumentProto {
+  // REQUIRED: Namespace that this Document resides in.
+  // Namespaces can affect read/write permissions.
+  optional string namespace = 1;
+
+  // REQUIRED: Identifier of the Document; must be unique within the
+  // Document's `namespace`. Otherwise, the new Document will override any
+  // other Documents with the same `namespace`+`uri` that Icing knows about.
+  optional string uri = 2;
+
+  // REQUIRED: Type of the Document. This should match the 'schema_type' of
+  // one of the types given to Icing as part of the overall schema.
+  // See icing.SchemaTypeConfigProto.schema_type for details.
+  optional string schema = 3;
+
+  // Milliseconds since epoch at which the Document was created. If not
+  // specified, it will default to when the Icing receives the Document.
+  optional uint64 creation_timestamp_ms = 4;
+
+  repeated PropertyProto properties = 5;
+}
+
+// Holds a property field of the Document.
+// Next tag: 8
+message PropertyProto {
+  // Name of the property. This should be the same as one of the properties
+  // already defined in the schema for this Document's schema_type.
+  // See icing.PropertyConfigProto.property_name for details.
+  optional string name = 1;
+
+  // Only the field corresponding to the DataType specified in
+  // icing.PropertyConfigProto.data_type should be set.
+  repeated string string_values = 2;
+  repeated int64 int64_values = 3;
+  repeated double double_values = 4;
+  repeated bool boolean_values = 5;
+  repeated bytes bytes_values = 6;
+  repeated DocumentProto document_values = 7;
+}
diff --git a/icing/proto/document_wrapper.proto b/icing/proto/document_wrapper.proto
new file mode 100644
index 0000000..d17faf9
--- /dev/null
+++ b/icing/proto/document_wrapper.proto
@@ -0,0 +1,30 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+import "icing/proto/document.proto";
+
+// DocumentWrapper as a wrapper of the user-facing DocumentProto is meant to
+// be used by icing team internally. It stores the original document provided
+// by library users and metadata of the document which shouldn't be exposed to
+// library users.
+message DocumentWrapper {
+  optional DocumentProto document = 1;
+
+  // Indicates if the document is marked as deleted
+  optional bool deleted = 2;
+}
diff --git a/icing/proto/icing-search-engine-options.proto b/icing/proto/icing-search-engine-options.proto
new file mode 100644
index 0000000..f3b98dc
--- /dev/null
+++ b/icing/proto/icing-search-engine-options.proto
@@ -0,0 +1,70 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+// Next tag: 6
+message IcingSearchEngineOptions {
+  // Directory to persist files for Icing. Required.
+  // If Icing was previously initialized with this directory, it will reload
+  // the index saved by the last instance.
+  optional string base_dir = 1;
+
+  // File path to the LangId language segmentation model for the library to use.
+  // Required.
+  optional string lang_model_path = 2;
+
+  // The maximum number of tokens to be allowed per document. If a document
+  // exceeds this number of tokens, then only the first max_tokens_per_doc
+  // will be indexed.
+  //
+  // Clients may use this value to prevent the possibility of a select few
+  // documents from exhausting limits in the index that are shared between all
+  // documents (ie max allowed index size).
+  //
+  // Valid values: [1, INT_MAX], Current default is 1/5 of the default of
+  // max_document_size.
+  // Optional.
+  optional int32 max_tokens_per_doc = 3 [default = 13107];
+
+  // The maximum allowable token length. All tokens in excess of this size
+  // will be truncated to max_token_length before being indexed.
+  //
+  // Clients may use this option to prevent unnecessary indexing of long tokens.
+  // Depending on the use case, indexing all of
+  // 'Supercalifragilisticexpialidocious' may be unnecessary - a user is
+  // unlikely to type that entire query. So only indexing the first n bytes may
+  // still provide the desired behavior without wasting resources.
+  //
+  // Valid values: [1, INT_MAX]
+  // Optional.
+  optional int32 max_token_length = 4 [default = 30];
+
+  // The size (measured in bytes) at which Icing's internal indices should be
+  // merged. Icing buffers changes together before merging them into a more
+  // compact format. When the buffer exceeds index_merge_size during a Put
+  // operation, the buffer is merged into the larger, more compact index.
+  //
+  // This more compact index is more efficient to search over as the index
+  // grows larger and has smaller system health impact.
+  //
+  // Setting a low index_merge_size increases the frequency of merges -
+  // increasing indexing-time latency and flash wear. Setting a high
+  // index_merge_size leads to larger resource usage and higher query latency.
+  // Valid values: [1, INT_MAX]
+  // Optional.
+  optional int32 index_merge_size = 5 [default = 1048576];  // 1 MiB
+}
diff --git a/icing/proto/schema.proto b/icing/proto/schema.proto
new file mode 100644
index 0000000..b0a6788
--- /dev/null
+++ b/icing/proto/schema.proto
@@ -0,0 +1,176 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+import "icing/proto/term.proto";
+
+// Defines the schema that every Document of a specific "type" should adhere
+// to. These can be considered as definitions of rich structured types for
+// Documents accepted by IcingSearchEngine.
+//
+// NOTE: Instances of SchemaTypeConfigProto are strongly recommended to be
+// based on types defined in schema.org. This makes the data/config/code more
+// shareable and easier to extend in the future.
+//
+// TODO(cassiewang) Define a sample proto file that can be used by tests and for
+// documentation.
+//
+// Next tag: 5
+message SchemaTypeConfigProto {
+  // REQUIRED: Named type that uniquely identifies the structured, logical
+  // schema being defined.
+  //
+  // Recommended format: Human readable string that's one of the types defined
+  // in http://schema.org. Eg: DigitalDocument, Message, Person, etc.
+  optional string schema_type = 1;
+
+  // The time-to-live that should be enforced on every Document of this type.
+  // Documents get garbage-collected based on their creation-timestamp and the
+  // TTL of the schema they belong to.
+  //
+  // Default value of 0 keeps the Documents till they're explicitly deleted.
+  optional int64 ttl_secs = 3;
+
+  // List of all properties that are supported by Documents of this type.
+  // An Document should never have properties that are not listed here.
+  //
+  // TODO(cassiewang) Figure out if we should disallow, ignore or accept
+  // unknown properties. Accepting them could make switching between versions
+  // easier.
+  repeated PropertyConfigProto properties = 4;
+
+  reserved 2;
+}
+
+// Describes how a single property should be indexed.
+// Next tag: 3
+message IndexingConfig {
+  // Indicates how the content of this property should be matched in the index.
+  //
+  // TermMatchType.Code=UNKNOWN
+  // Content in this section will not be tokenized or indexed. Useful if the
+  // data type is not made up of terms (e.g. DOCUMENT or BYTES type). All the
+  // properties inside the nested property won't be indexed regardless of the
+  // value of the term_match_type field for the nested properties.
+  //
+  // TermMatchType.Code=EXACT_ONLY
+  // Content in this section should only be returned for queries matching the
+  // exact tokens appearing in this section.
+  // Ex. A section with "fool" should NOT match a query for "foo".
+  //
+  // TermMatchType.Code=PREFIX
+  // Content in this section should be returned for queries that are either
+  // exact matches or query matches of the tokens appearing in this section.
+  // Ex. A section with "fool" *should* match a query for "foo".
+  optional TermMatchType.Code term_match_type = 1;
+
+  message TokenizerType {
+    enum Code {
+      // It is only valid for tokenizer_type to be 'NONE' if either indexed is
+      // also 'NONE' or the data type is DOCUMENT.
+      NONE = 0;
+
+      // Tokenization for plain text.
+      PLAIN = 1;
+    }
+  }
+  optional TokenizerType.Code tokenizer_type = 2;
+}
+
+// Describes the schema of a single property of Documents that belong to a
+// specific SchemaTypeConfigProto. These can be considered as a rich, structured
+// type for each property of Documents accepted by IcingSearchEngine.
+// Next tag: 6
+message PropertyConfigProto {
+  // REQUIRED: Name that uniquely identifies a property within an Document of
+  // a specific SchemaTypeConfigProto.
+  //
+  // Recommended format: Human readable string that's one of the properties
+  // defined in schema.org for the parent SchemaTypeConfigProto.
+  // Eg: 'author' for http://schema.org/DigitalDocument.
+  // Eg: 'address' for http://schema.org/Place.
+  optional string property_name = 1;
+
+  // REQUIRED: Physical data-types of the contents of the property.
+  message DataType {
+    enum Code {
+      // This should never purposely be set. This is used for backwards
+      // compatibility reasons.
+      UNKNOWN = 0;
+      STRING = 1;
+      INT64 = 2;
+      DOUBLE = 3;
+      BOOLEAN = 4;
+
+      // Unstructured BLOB.
+      BYTES = 5;
+
+      // Indicates that the property itself is an Document, making it part
+      // a hierarchical Document schema. Any property using this data_type
+      // MUST have a valid 'schema_type'.
+      DOCUMENT = 6;
+    }
+  }
+  optional DataType.Code data_type = 2;
+
+  // REQUIRED if (data_type == DOCUMENT). OPTIONAL otherwise.
+  // Indicates the logical schema-type of the contents of this property.
+  //
+  // TODO(cassiewang): This could be useful for non-document properties, e.g.
+  // to set this field as a schema.org/address for some string property.
+  // Re-evaluate what recommendation we should give clients if we want to start
+  // using this for non-document properties as well.
+  //
+  // Recommended format: Human readable string that is one of the types defined
+  // in schema.org, matching the SchemaTypeConfigProto.schema_type of another
+  // type.
+  optional string schema_type = 3;
+
+  // REQUIRED: The cardinality of the property.
+  message Cardinality {
+    // NOTE: The order of the cardinality is purposefully set to be from least
+    // restrictive (REPEATED) to most restrictive (REQUIRED). This makes it
+    // easier to check if a field is backwards compatible by doing a simple
+    // greater-than/less-than check on the enum ints. Changing/adding new
+    // cardinalities should be done cautiously.
+    enum Code {
+      // This should never purposely be set. This is used for backwards
+      // compatibility reasons.
+      UNKNOWN = 0;
+
+      // Any number of items (including zero) [0...*].
+      REPEATED = 1;
+
+      // Zero or one value [0,1].
+      OPTIONAL = 2;
+
+      // Exactly one value [1].
+      REQUIRED = 3;
+    }
+  }
+  optional Cardinality.Code cardinality = 4;
+
+  // OPTIONAL: Properties that do not set the indexing config will not be
+  // indexed.
+  optional IndexingConfig indexing_config = 5;
+}
+
+// List of all supported types constitutes the schema used by Icing.
+// Next tag: 2
+message SchemaProto {
+  repeated SchemaTypeConfigProto types = 1;
+}
diff --git a/icing/proto/search.proto b/icing/proto/search.proto
new file mode 100644
index 0000000..b153de8
--- /dev/null
+++ b/icing/proto/search.proto
@@ -0,0 +1,103 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+import "icing/proto/document.proto";
+import "icing/proto/term.proto";
+
+// Client-supplied specifications on what documents to retrieve.
+// Next tag: 3
+message SearchSpecProto {
+  // REQUIRED: The "raw" query string that users may type. For example, "cat"
+  // will search for documents with the term cat in it.
+  optional string query = 1;
+
+  // Indicates how the query terms should match terms in the index.
+  //
+  // TermMatchType.Code=UNKNOWN
+  // Should never purposely be set and may lead to undefined behavior. This is
+  // used for backwards compatibility reasons.
+  //
+  // TermMatchType.Code=EXACT_ONLY
+  // Query terms will only match exact tokens in the index.
+  // Ex. A query term "foo" will only match indexed token "foo", and not "foot"
+  // or "football"
+  //
+  // TermMatchType.Code=PREFIX
+  // Query terms will match indexed tokens when the query term is a prefix of
+  // the token.
+  // Ex. A query term "foo" will match indexed tokens like "foo", "foot", and
+  // "football".
+  optional TermMatchType.Code term_match_type = 2;
+
+  // TODO(cassiewang): add namespace restricts
+  // TODO(cassiewang): add schema type restricts
+}
+
+// Client-supplied specifications on what to include/how to format the search
+// results.
+// Next tag: 3
+message ResultSpecProto {
+  // The maximum number of documents to return in SearchResultProto. Even if
+  // more documents have matched the SearchSpecProto, this may be used to limit
+  // the number to actually return to the client.
+  optional int32 limit = 1 [default = 10];
+
+  // Whether to collect and return debug_info in the SearchResultProto.
+  optional bool debug_info = 2;
+}
+
+// Icing lib-supplied results from a search results.
+// Next tag: 4
+message SearchResultProto {
+  // Documents that match the SearchSpecProto. Empty if there was an error.
+  repeated DocumentProto documents = 1;
+
+  // Details on what errors were encountered. Not populated if there were no
+  // errors.
+  message ErrorProto {
+    // Generic category of errors.
+    enum Status {
+      UNKNOWN = 0;
+      // TODO(cassiewang): Add more as use-cases come up
+    }
+    optional Status status = 1;
+
+    // A more descriptive message on the error. Useful during debugging
+    optional string error_message = 2;
+  }
+  optional ErrorProto error = 2;
+
+  // Various debug fields. Not populated if ResultSpecProto.debug_info = false.
+  message DebugInfoProto {
+    // The number of results that actually matched the SearchSpecProto. This is
+    // different from the number of `documents` returned since the user can
+    // set a ResultSpecProto.limit on how many results are returned to them.
+    optional uint64 num_results = 1;
+
+    // Latency to parse and execute the query, in milliseconds.
+    optional uint64 latency_ms = 2;
+
+    // The internal representation of the actual query string that was executed.
+    // This may be different from the SearchSpecProto.query if the original
+    // query was malformed.
+    optional string executed_query = 3;
+  }
+  optional DebugInfoProto debug_info = 3;
+}
+
+// TODO(cassiewang): Add a ScoringSpec.
diff --git a/icing/proto/term.proto b/icing/proto/term.proto
new file mode 100644
index 0000000..b2cffdf
--- /dev/null
+++ b/icing/proto/term.proto
@@ -0,0 +1,35 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package icing;
+
+// Encapsulates the configurations on how Icing should query/index these terms.
+// Next tag: 0
+message TermMatchType {
+  // Next tag: 3
+  enum Code {
+    // A default for all other use-cases.
+    UNKNOWN = 0;
+
+    // A term is an exact term.
+    // Ex. "foot" means "foot", and is not related to "foo" or "football"
+    EXACT_ONLY = 1;
+
+    // A term is a prefix of other terms.
+    // Ex. "foo" is a prefix of "foot"
+    PREFIX = 2;
+  }
+}