components/optimization_guide/proto/hints.proto - chromium/src - Git at Google

 // Copyright 2017 The Chromium Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 syntax = "proto2";
 option optimize_for = LITE_RUNTIME;
 option java_package = "org.chromium.components.optimization_guide.proto";
 option java_outer_classname = "HintsProto";

 package optimization_guide.proto;

 import "components/optimization_guide/proto/common_types.proto";
 import "components/optimization_guide/proto/loading_predictor_metadata.proto";

 // Information about the hint that the client already has for a host.
 message MatchedHintInfo {
   // Describes the granularity of the key field.
   optional KeyRepresentation key_representation = 1;
   // The key of the hint currently used for the host.
   optional string key = 2;
   // The version of the hint for this key already stored on the client.
   optional int64 version = 3;
 }

 message HostInfo {
   // Host that the client is requesting information for.
   optional string host = 1;
   // Information about the hint that the client already has for the host.
   optional MatchedHintInfo matched_hint = 2;
 }

 // Information about a URL to request hints for.
 message UrlInfo {
   // The URL that the client is requesting information for.
   optional string url = 1;
 }

 // Information about the set of host hashes to retrieve hints for.
 message HashedHostInfos {
   // The partial host hash will be the first num_hash_bits least significant bit
   // of the hashed host.
   repeated uint32 partial_host_hashes = 1;
   optional uint32 num_hash_bits = 2;
 }

 // Request to return a set of hints that guide what optimizations to perform
 // on those hosts.
 message GetHintsRequest {
   reserved 6;

   // Information about the set of hosts to retrieve hints for.
   repeated HostInfo hosts = 1;

   // Information about the set of URLs to retrieve hints for.
   repeated UrlInfo urls = 4;

   // Information about the set of host hashes to retrieve hints for.
   optional HashedHostInfos hashed_hosts = 8;

   // The set of optimization types that the requesting client can support
   // and perform.
   //
   // It is guaranteed that the response will only contain hints for
   // optimizations present in this set.
   repeated OptimizationType supported_optimizations = 2;

   // The set of key representations that the client can process.
   //
   // It is guaranteed that the response will only contain hints for key
   // representations present in this set. If not specified,
   // [HOST_SUFFIX, FULL_URL] will be used.
   repeated KeyRepresentation supported_key_representations = 5;

   // Context in which this request is made.
   optional RequestContext context = 3;

   // The locale to associate with this request.
   //
   // It is the IETF language tag, defined in BCP 47. The region subtag is not
   // included when it adds no distinguishing information to the language tag
   // (e.g. both "en-US" and "fr" are correct here).
   optional string locale = 7;

   // Information about the request origin.
   optional OriginInfo origin_info = 9;
 }

 // Response to the GetHints request.
 message GetHintsResponse {
   // An ordered list containing hints for key/optimization combinations.
   //
   // It is guaranteed that there will only be a single hint per key and key
   // representation combination. These hints are intended to apply to a full
   // page. It is expected that the client will use the Hint record with the
   // most specific key that matches the main frame URL.
   repeated Hint hints = 1;

   // The maximum duration in which the hints, or lack of hints, provided in
   // this response are valid.
   optional Duration max_cache_duration = 2;

   // A set of hint keys to remove from the client cache.
   //
   // It is guaranteed that all entries in this list were provided by the client
   // in the corresponding request's |hosts.matched_hint| fields.
   //
   // It is expected for the client to immediately stop using all hints contained
   // in this field. Hints that are not present in |hints| or in this field
   // should adhere to the client cache's existing expiration policy.
   repeated MatchedHintInfo hints_to_remove = 3;
 }

 // Must sync with enum OptimizationType in enums.xml for metric recording.
 enum OptimizationType {
   // Values for obsolete optimizations.
   reserved 11, 12, 29;

   TYPE_UNSPECIFIED = 0;
   // This optimization blocks JavaScript on the page.
   NOSCRIPT = 1;
   // This optimization applies a set of ResourceLoadingHint(s) to load the
   // page.
   RESOURCE_LOADING = 2;
   // This optimization redirects the navigation through a lite page server.
   LITE_PAGE_REDIRECT = 3;
   // This optimization does validation of metadata fetch on navigation.
   METADATA_FETCH_VALIDATION = 4;
   // This optimization defers execution of parser-blocking script until after
   // parsing completes.
   DEFER_ALL_SCRIPT = 5;
   // This optimization is used to provide aggregated performance information
   // about the page and pages it links to.
   PERFORMANCE_HINTS = 6;
   // This optimization allows page loads going through the data reduction
   // proxy to be transformed by the proxy.
   LITE_PAGE = 7;
   // This optimization compresses public images.
   COMPRESS_PUBLIC_IMAGES = 8;
   // This optimization provides the Loading Predictor with resources predicted
   // to be on the page.
   LOADING_PREDICTOR = 9;
   // This optimization provides information about hosts that historically
   // provide a fast and responsive user experience.
   FAST_HOST_HINTS = 10;
   // This optimization provides information about how to throttle meda requests
   // to reduce the bitrate of adaptively streamed media.
   LITE_VIDEO = 13;
   // This optimization is used to provide aggregated performance information
   // about pages linked to from the current page.
   LINK_PERFORMANCE = 14;
   // Detects if a page is a shopping page or not. A tradeoff has been made here
   // where the number of shopping page predictions for non-shopping pages is
   // increased to reduce the number of non-shopping page predictions for
   // shopping pages.
   SHOPPING_PAGE_PREDICTOR = 15;
   // This optimization provides information about hosts that are identified as
   // commonly logged-in.
   LOGIN_DETECTION = 16;
   // Provides key information about the merchant represented by the current
   // host.
   MERCHANT_TRUST_SIGNALS = 17;
   // Provides pricing data so the user can track prices and price updates.
   PRICE_TRACKING = 18;
   // This optimization does validation of bloom filter.
   BLOOM_FILTER_VALIDATION = 19;
   // Provides 'About this site' data about the site being visited.
   ABOUT_THIS_SITE = 20;
   // Provides key information about the merchant represented by the current
   // host -- VERSION 2.
   MERCHANT_TRUST_SIGNALS_V2 = 21;
   // Provides the entities that are present on the page.
   PAGE_ENTITIES = 22;
   // This optimization provides information for whether a page should be
   // included in a history cluster.
   HISTORY_CLUSTERS = 23;
   // Determines if a page is eligible for 'Thank creator' functionality.
   THANK_CREATOR_ELIGIBLE = 24;
   // This optimization provides information about hosts that are blocked for
   // IBAN autofill.
   IBAN_AUTOFILL_BLOCKED = 25;
   // This optimization provides information about images for a URL.
   SALIENT_IMAGE = 26;
   // This optimization provides information about a sampling rate of Autofill
   // UKM metrics per origin based on origin popularity.
   AUTOFILL_SAMPLING_RATE = 27;
   // This optimization provides information about whether a merchant is
   // opted-out of Visa virtual cards for a URL.
   VCN_MERCHANT_OPT_OUT_VISA = 28;
 }

 // Presents semantics for how page load URLs should be matched.
 enum KeyRepresentation {
   REPRESENTATION_UNSPECIFIED = 0;
   // The suffix to match in the hostname of a page load URL.
   //
   // Example: A host suffix of example.com would match pages with host
   // sports.example.com, but not fooexample.com.
   HOST_SUFFIX = 1 [deprecated = true];
   // The full URL to match.
   //
   // This will be an exact match of a page load URL, including query params and
   // fragments.
   FULL_URL = 2;
   // The host to match.
   //
   // This will be an exact match of a page load host.
   HOST = 3;
   // This will be a partial hash of a page load host.
   HASHED_HOST = 4;
 }

 message Optimization {
   reserved 2, 3, 4, 5, 10, 11, 12, 14;
   // The type of optimization the hint applies to.
   optional OptimizationType optimization_type = 1;
   // The version of the tuning group for the optimization type.
   //
   // This will only be populated if this optimization is being autotuned.
   //
   // If this is set to UINT64_MAX, this optimization should be considered as
   // not allowed and was only included for metrics purposes.
   optional uint64 tuning_version = 6;
   // The metadata associated with the optimization type.
   //
   // It is expected that the client and server have agreed upon the appropriate
   // metadata type for the optimization type.
   //
   // New clients should utilize any_metadata rather than adding another field.
   oneof metadata {
     LoadingPredictorMetadata loading_predictor_metadata = 13;
     Any any_metadata = 15;
   }
 }

 message PageHint {
   reserved 2;

   // The pattern to match against the committed page URL.
   //
   // The pattern may be a single substring to match against the full URL or it
   // may be an ordered set of substrings to match where the substrings are
   // separated by the ‘*’ wildcard character (with an implicit ‘*’ at the
   // beginning and end).
   optional string page_pattern = 1;
   // An ordered set of optimizations that should be allowlisted for this page
   // pattern.
   //
   // The client will use the first optimization that it supports.
   repeated Optimization allowlisted_optimizations = 3;
 }

 message Hint {
   // Describes the granularity of the key field.
   optional KeyRepresentation key_representation = 1;
   // The key that applies to this hint. The key_representation field describes
   // the form in which this key takes. Guaranteed to be non-empty.
   optional string key = 2;
   // An unordered set of optimizations that should be allowlisted for this
   // hint.
   //
   // This field is currently only specified for key_representation of HOST.
   repeated Optimization allowlisted_optimizations = 3;
   // An ordered set of per-page hints. Only the first PageHint record
   // that matches a committed page URL should be used for that page load.
   repeated PageHint page_hints = 4;
   // Version that generated this hint.
   //
   // It is expected that this version be sent along with subsequent requests
   // for hosts that match this hint.
   optional string version = 5;
   // The maximum duration for which the hint should be used for.
   optional Duration max_cache_duration = 6;
 }

 // Configuration and data for a Bloom filter.
 //
 // Note that some additional aspects of the BloomFilter are separately
 // specified between the client and server including the specific MurmurHash3
 // hashing function, how the hashing function is seeded, how bits are
 // addressed in the byte vector, and the nature of the strings that the
 // Bloom filter holds (whether host, host suffix, URL path, etc.).
 message BloomFilter {
   // Specifies the number of hash functions to use in the Bloom filter.
   // This essentially means how many bits will be set in the bit array
   // for a string member of the Bloom filter.
   optional uint32 num_hash_functions = 1;
   // The number of bits in the Bloom filter's bit array.
   optional uint32 num_bits = 2;
   // The bit array data of the Bloom filter provided via a byte vector.
   // The number of bytes provided must be large enough to hold the
   // specified number of bits (num_bits).
   optional bytes data = 3;
 }

 // A scalable filter for an optimization type.
 //
 // Next ID: 6
 message OptimizationFilter {
   // The type of optimization this filter applies to.
   optional OptimizationType optimization_type = 1;
   // The filter data represented as a Bloom filter.
   optional BloomFilter bloom_filter = 2;
   // Additional filters represented as regexps matched against the main page
   // URL. If matched, the URL will be considered as contained in the filter.
   repeated string regexps = 3;
   // Additional filters represented as regexps matched against the main page
   // URL. If matched, the URL will be considered as not contained in the filter.
   //
   // This set of regexps should be checked prior to any matching against the
   // contained bloom_filter or regexps fields.
   repeated string exclusion_regexps = 5;
   // Whether additional host suffixes (other than the host) should be checked
   // against the filter.
   optional bool skip_host_suffix_checking = 4;
 }

 message Configuration {
   // An ordered list containing hints for key/optimization combinations.
   //
   // It is guaranteed that there will only be a single hint per key and key
   // representation combination. These hints are intended to apply to a full
   // page.
   //
   // Note, this list may contain multiple hints that apply to a page. For
   // example, if there are hints for (HOST_SUFFIX,example.com) and
   // (HOST_SUFFIX,sports.example.com), these may both apply to
   // sports.example.com/foo.
   //
   // The client will use the first Hint record with a key that matches the
   // main frame URL. Therefore, the server should provide all the hint
   // details for that key that it wants to provide as the client will only
   // look at that one record to decide which optimization to apply.
   repeated Hint hints = 1;
   // A set of per-optimization blocklists.
   //
   // It is guaranteed that an optimization type will not have filters in both
   // |optimization_blocklists| and |optimization_allowlists|.
   repeated OptimizationFilter optimization_blocklists = 2;
   // A set of per-optimization allowlists.
   //
   // It is guaranteed that an optimization type will not have filters in both
   // |optimization_blocklists| and |optimization_allowlists|.
   repeated OptimizationFilter optimization_allowlists = 3;
 }

 enum HintSource {
   HINT_SOURCE_UNKNOWN = 0;
   // Served from the Chrome Optimization Hints Component.
   HINT_SOURCE_OPTIMIZATION_HINTS_COMPONENT = 1;
   // Served from the Chrome Optimization Guide Service.
   HINT_SOURCE_OPTIMIZATION_GUIDE_SERVICE = 2;
 }

 message Version {
   reserved 2;

   // The time the hint was generated.
   optional Timestamp generation_timestamp = 1;
   // The source from which the hint was served from.
   optional HintSource hint_source = 3;
 }
	// Copyright 2017 The Chromium Authors
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	syntax = "proto2";
	option optimize_for = LITE_RUNTIME;
	option java_package = "org.chromium.components.optimization_guide.proto";
	option java_outer_classname = "HintsProto";

	package optimization_guide.proto;

	import "components/optimization_guide/proto/common_types.proto";
	import "components/optimization_guide/proto/loading_predictor_metadata.proto";

	// Information about the hint that the client already has for a host.
	message MatchedHintInfo {
	// Describes the granularity of the key field.
	optional KeyRepresentation key_representation = 1;
	// The key of the hint currently used for the host.
	optional string key = 2;
	// The version of the hint for this key already stored on the client.
	optional int64 version = 3;
	}

	message HostInfo {
	// Host that the client is requesting information for.
	optional string host = 1;
	// Information about the hint that the client already has for the host.
	optional MatchedHintInfo matched_hint = 2;
	}

	// Information about a URL to request hints for.
	message UrlInfo {
	// The URL that the client is requesting information for.
	optional string url = 1;
	}

	// Information about the set of host hashes to retrieve hints for.
	message HashedHostInfos {
	// The partial host hash will be the first num_hash_bits least significant bit
	// of the hashed host.
	repeated uint32 partial_host_hashes = 1;
	optional uint32 num_hash_bits = 2;
	}

	// Request to return a set of hints that guide what optimizations to perform
	// on those hosts.
	message GetHintsRequest {
	reserved 6;

	// Information about the set of hosts to retrieve hints for.
	repeated HostInfo hosts = 1;

	// Information about the set of URLs to retrieve hints for.
	repeated UrlInfo urls = 4;

	// Information about the set of host hashes to retrieve hints for.
	optional HashedHostInfos hashed_hosts = 8;

	// The set of optimization types that the requesting client can support
	// and perform.
	//
	// It is guaranteed that the response will only contain hints for
	// optimizations present in this set.
	repeated OptimizationType supported_optimizations = 2;

	// The set of key representations that the client can process.
	//
	// It is guaranteed that the response will only contain hints for key
	// representations present in this set. If not specified,
	// [HOST_SUFFIX, FULL_URL] will be used.
	repeated KeyRepresentation supported_key_representations = 5;

	// Context in which this request is made.
	optional RequestContext context = 3;

	// The locale to associate with this request.
	//
	// It is the IETF language tag, defined in BCP 47. The region subtag is not
	// included when it adds no distinguishing information to the language tag
	// (e.g. both "en-US" and "fr" are correct here).
	optional string locale = 7;

	// Information about the request origin.
	optional OriginInfo origin_info = 9;
	}

	// Response to the GetHints request.
	message GetHintsResponse {
	// An ordered list containing hints for key/optimization combinations.
	//
	// It is guaranteed that there will only be a single hint per key and key
	// representation combination. These hints are intended to apply to a full
	// page. It is expected that the client will use the Hint record with the
	// most specific key that matches the main frame URL.
	repeated Hint hints = 1;

	// The maximum duration in which the hints, or lack of hints, provided in
	// this response are valid.
	optional Duration max_cache_duration = 2;

	// A set of hint keys to remove from the client cache.
	//
	// It is guaranteed that all entries in this list were provided by the client
	// in the corresponding request's \|hosts.matched_hint\| fields.
	//
	// It is expected for the client to immediately stop using all hints contained
	// in this field. Hints that are not present in \|hints\| or in this field
	// should adhere to the client cache's existing expiration policy.
	repeated MatchedHintInfo hints_to_remove = 3;
	}

	// Must sync with enum OptimizationType in enums.xml for metric recording.
	enum OptimizationType {
	// Values for obsolete optimizations.
	reserved 11, 12, 29;

	TYPE_UNSPECIFIED = 0;
	// This optimization blocks JavaScript on the page.
	NOSCRIPT = 1;
	// This optimization applies a set of ResourceLoadingHint(s) to load the
	// page.
	RESOURCE_LOADING = 2;
	// This optimization redirects the navigation through a lite page server.
	LITE_PAGE_REDIRECT = 3;
	// This optimization does validation of metadata fetch on navigation.
	METADATA_FETCH_VALIDATION = 4;
	// This optimization defers execution of parser-blocking script until after
	// parsing completes.
	DEFER_ALL_SCRIPT = 5;
	// This optimization is used to provide aggregated performance information
	// about the page and pages it links to.
	PERFORMANCE_HINTS = 6;
	// This optimization allows page loads going through the data reduction
	// proxy to be transformed by the proxy.
	LITE_PAGE = 7;
	// This optimization compresses public images.
	COMPRESS_PUBLIC_IMAGES = 8;
	// This optimization provides the Loading Predictor with resources predicted
	// to be on the page.
	LOADING_PREDICTOR = 9;
	// This optimization provides information about hosts that historically
	// provide a fast and responsive user experience.
	FAST_HOST_HINTS = 10;
	// This optimization provides information about how to throttle meda requests
	// to reduce the bitrate of adaptively streamed media.
	LITE_VIDEO = 13;
	// This optimization is used to provide aggregated performance information
	// about pages linked to from the current page.
	LINK_PERFORMANCE = 14;
	// Detects if a page is a shopping page or not. A tradeoff has been made here
	// where the number of shopping page predictions for non-shopping pages is
	// increased to reduce the number of non-shopping page predictions for
	// shopping pages.
	SHOPPING_PAGE_PREDICTOR = 15;
	// This optimization provides information about hosts that are identified as
	// commonly logged-in.
	LOGIN_DETECTION = 16;
	// Provides key information about the merchant represented by the current
	// host.
	MERCHANT_TRUST_SIGNALS = 17;
	// Provides pricing data so the user can track prices and price updates.
	PRICE_TRACKING = 18;
	// This optimization does validation of bloom filter.
	BLOOM_FILTER_VALIDATION = 19;
	// Provides 'About this site' data about the site being visited.
	ABOUT_THIS_SITE = 20;
	// Provides key information about the merchant represented by the current
	// host -- VERSION 2.
	MERCHANT_TRUST_SIGNALS_V2 = 21;
	// Provides the entities that are present on the page.
	PAGE_ENTITIES = 22;
	// This optimization provides information for whether a page should be
	// included in a history cluster.
	HISTORY_CLUSTERS = 23;
	// Determines if a page is eligible for 'Thank creator' functionality.
	THANK_CREATOR_ELIGIBLE = 24;
	// This optimization provides information about hosts that are blocked for
	// IBAN autofill.
	IBAN_AUTOFILL_BLOCKED = 25;
	// This optimization provides information about images for a URL.
	SALIENT_IMAGE = 26;
	// This optimization provides information about a sampling rate of Autofill
	// UKM metrics per origin based on origin popularity.
	AUTOFILL_SAMPLING_RATE = 27;
	// This optimization provides information about whether a merchant is
	// opted-out of Visa virtual cards for a URL.
	VCN_MERCHANT_OPT_OUT_VISA = 28;
	}

	// Presents semantics for how page load URLs should be matched.
	enum KeyRepresentation {
	REPRESENTATION_UNSPECIFIED = 0;
	// The suffix to match in the hostname of a page load URL.
	//
	// Example: A host suffix of example.com would match pages with host
	// sports.example.com, but not fooexample.com.
	HOST_SUFFIX = 1 [deprecated = true];
	// The full URL to match.
	//
	// This will be an exact match of a page load URL, including query params and
	// fragments.
	FULL_URL = 2;
	// The host to match.
	//
	// This will be an exact match of a page load host.
	HOST = 3;
	// This will be a partial hash of a page load host.
	HASHED_HOST = 4;
	}

	message Optimization {
	reserved 2, 3, 4, 5, 10, 11, 12, 14;
	// The type of optimization the hint applies to.
	optional OptimizationType optimization_type = 1;
	// The version of the tuning group for the optimization type.
	//
	// This will only be populated if this optimization is being autotuned.
	//
	// If this is set to UINT64_MAX, this optimization should be considered as
	// not allowed and was only included for metrics purposes.
	optional uint64 tuning_version = 6;
	// The metadata associated with the optimization type.
	//
	// It is expected that the client and server have agreed upon the appropriate
	// metadata type for the optimization type.
	//
	// New clients should utilize any_metadata rather than adding another field.
	oneof metadata {
	LoadingPredictorMetadata loading_predictor_metadata = 13;
	Any any_metadata = 15;
	}
	}

	message PageHint {
	reserved 2;

	// The pattern to match against the committed page URL.
	//
	// The pattern may be a single substring to match against the full URL or it
	// may be an ordered set of substrings to match where the substrings are
	// separated by the ‘’ wildcard character (with an implicit ‘’ at the
	// beginning and end).
	optional string page_pattern = 1;
	// An ordered set of optimizations that should be allowlisted for this page
	// pattern.
	//
	// The client will use the first optimization that it supports.
	repeated Optimization allowlisted_optimizations = 3;
	}

	message Hint {
	// Describes the granularity of the key field.
	optional KeyRepresentation key_representation = 1;
	// The key that applies to this hint. The key_representation field describes
	// the form in which this key takes. Guaranteed to be non-empty.
	optional string key = 2;
	// An unordered set of optimizations that should be allowlisted for this
	// hint.
	//
	// This field is currently only specified for key_representation of HOST.
	repeated Optimization allowlisted_optimizations = 3;
	// An ordered set of per-page hints. Only the first PageHint record
	// that matches a committed page URL should be used for that page load.
	repeated PageHint page_hints = 4;
	// Version that generated this hint.
	//
	// It is expected that this version be sent along with subsequent requests
	// for hosts that match this hint.
	optional string version = 5;
	// The maximum duration for which the hint should be used for.
	optional Duration max_cache_duration = 6;
	}

	// Configuration and data for a Bloom filter.
	//
	// Note that some additional aspects of the BloomFilter are separately
	// specified between the client and server including the specific MurmurHash3
	// hashing function, how the hashing function is seeded, how bits are
	// addressed in the byte vector, and the nature of the strings that the
	// Bloom filter holds (whether host, host suffix, URL path, etc.).
	message BloomFilter {
	// Specifies the number of hash functions to use in the Bloom filter.
	// This essentially means how many bits will be set in the bit array
	// for a string member of the Bloom filter.
	optional uint32 num_hash_functions = 1;
	// The number of bits in the Bloom filter's bit array.
	optional uint32 num_bits = 2;
	// The bit array data of the Bloom filter provided via a byte vector.
	// The number of bytes provided must be large enough to hold the
	// specified number of bits (num_bits).
	optional bytes data = 3;
	}

	// A scalable filter for an optimization type.
	//
	// Next ID: 6
	message OptimizationFilter {
	// The type of optimization this filter applies to.
	optional OptimizationType optimization_type = 1;
	// The filter data represented as a Bloom filter.
	optional BloomFilter bloom_filter = 2;
	// Additional filters represented as regexps matched against the main page
	// URL. If matched, the URL will be considered as contained in the filter.
	repeated string regexps = 3;
	// Additional filters represented as regexps matched against the main page
	// URL. If matched, the URL will be considered as not contained in the filter.
	//
	// This set of regexps should be checked prior to any matching against the
	// contained bloom_filter or regexps fields.
	repeated string exclusion_regexps = 5;
	// Whether additional host suffixes (other than the host) should be checked
	// against the filter.
	optional bool skip_host_suffix_checking = 4;
	}

	message Configuration {
	// An ordered list containing hints for key/optimization combinations.
	//
	// It is guaranteed that there will only be a single hint per key and key
	// representation combination. These hints are intended to apply to a full
	// page.
	//
	// Note, this list may contain multiple hints that apply to a page. For
	// example, if there are hints for (HOST_SUFFIX,example.com) and
	// (HOST_SUFFIX,sports.example.com), these may both apply to
	// sports.example.com/foo.
	//
	// The client will use the first Hint record with a key that matches the
	// main frame URL. Therefore, the server should provide all the hint
	// details for that key that it wants to provide as the client will only
	// look at that one record to decide which optimization to apply.
	repeated Hint hints = 1;
	// A set of per-optimization blocklists.
	//
	// It is guaranteed that an optimization type will not have filters in both
	// \|optimization_blocklists\| and \|optimization_allowlists\|.
	repeated OptimizationFilter optimization_blocklists = 2;
	// A set of per-optimization allowlists.
	//
	// It is guaranteed that an optimization type will not have filters in both
	// \|optimization_blocklists\| and \|optimization_allowlists\|.
	repeated OptimizationFilter optimization_allowlists = 3;
	}

	enum HintSource {
	HINT_SOURCE_UNKNOWN = 0;
	// Served from the Chrome Optimization Hints Component.
	HINT_SOURCE_OPTIMIZATION_HINTS_COMPONENT = 1;
	// Served from the Chrome Optimization Guide Service.
	HINT_SOURCE_OPTIMIZATION_GUIDE_SERVICE = 2;
	}

	message Version {
	reserved 2;

	// The time the hint was generated.
	optional Timestamp generation_timestamp = 1;
	// The source from which the hint was served from.
	optional HintSource hint_source = 3;
	}