Plumb session tokens for signed-out feed requests.

Bug: 1110384
Change-Id: I7c0324071625e4bf25e3b797d5a1fb60bdedd1c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2476134Reviewed-by: Dan H <harringtond@chromium.org>
Reviewed-by: Carlos Knippschild <carlosk@chromium.org>
Commit-Queue: Roger McFarlane <rogerm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826859}

chrome/android/feed/core/java/src/org/chromium/chrome/browser/feed/v2/FeedStreamSurface.java

@@ -359,6 +359,10 @@ public class FeedStreamSurface implements SurfaceActionsHandler, FeedActionsHand
 
         @Override
         public String getAccountName() {
+            // Don't return account name if there's a signed-out session ID.
+            if (!getSignedOutSessionId().isEmpty()) {
+                return "";
+            }
             assert ThreadUtils.runningOnUiThread();
             CoreAccountInfo primaryAccount =
                     IdentityServicesProvider.get()
@@ -375,9 +379,20 @@ public class FeedStreamSurface implements SurfaceActionsHandler, FeedActionsHand
 
         @Override
         public String getClientInstanceId() {
+            // Don't return client instance id if there's a signed-out session ID.
+            if (!getSignedOutSessionId().isEmpty()) {
+                return "";
+            }
             assert ThreadUtils.runningOnUiThread();
             return FeedServiceBridge.getClientInstanceId();
         }
+
+        @Override
+        public String getSignedOutSessionId() {
+            assert ThreadUtils.runningOnUiThread();
+            return FeedStreamSurfaceJni.get().getSessionId(
+                    mNativeFeedStreamSurface, FeedStreamSurface.this);
+        }
     }
 
     /**
@@ -1173,6 +1188,7 @@ public class FeedStreamSurface implements SurfaceActionsHandler, FeedActionsHand
         long init(FeedStreamSurface caller);
         boolean isActivityLoggingEnabled(long nativeFeedStreamSurface, FeedStreamSurface caller);
         int[] getExperimentIds();
+        String getSessionId(long nativeFeedStreamSurface, FeedStreamSurface caller);
         void reportFeedViewed(long nativeFeedStreamSurface, FeedStreamSurface caller);
         void reportSliceViewed(
                 long nativeFeedStreamSurface, FeedStreamSurface caller, String sliceId);

chrome/browser/android/feed/v2/feed_stream_surface.cc

@@ -172,6 +172,13 @@ bool FeedStreamSurface::IsActivityLoggingEnabled(
   return feed_stream_api_ && feed_stream_api_->IsActivityLoggingEnabled();
 }
 
+base::android::ScopedJavaLocalRef<jstring> FeedStreamSurface::GetSessionId(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj) {
+  return base::android::ConvertUTF8ToJavaString(
+      env, feed_stream_api_ ? feed_stream_api_->GetSessionId() : std::string());
+}
+
 void FeedStreamSurface::ReportOpenAction(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj,

chrome/browser/android/feed/v2/feed_stream_surface.h

@@ -66,11 +66,16 @@ class FeedStreamSurface : public FeedStreamApi::SurfaceInterface {
   void SurfaceClosed(JNIEnv* env,
                      const base::android::JavaParamRef<jobject>& obj);
 
-  // Is activity Loggine enabled (ephemeral).
+  // Is activity logging enabled (ephemeral).
   bool IsActivityLoggingEnabled(
       JNIEnv* env,
       const base::android::JavaParamRef<jobject>& obj);
 
+  // Get the signed-out session id, if any (ephemeral).
+  base::android::ScopedJavaLocalRef<jstring> GetSessionId(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& obj);
+
   // Event reporting functions. These have no side-effect beyond recording
   // metrics. See |FeedStreamApi| for definitions.
   void ReportSliceViewed(JNIEnv* env,

components/feed/core/proto/BUILD.gn

@@ -28,6 +28,7 @@ proto_library("proto_v2") {
     "v2/ui.proto",
     "v2/wire/action_payload.proto",
     "v2/wire/capability.proto",
+    "v2/wire/chrome_client_info.proto",
     "v2/wire/chrome_feed_response_metadata.proto",
     "v2/wire/chrome_fulfillment_info.proto",
     "v2/wire/client_info.proto",

components/feed/core/proto/v2/store.proto

@@ -51,15 +51,24 @@ message StreamData {
   bool logging_enabled = 8;
   // Has the privacy notice been fulfilled?
   bool privacy_notice_fulfilled = 9;
+
   reserved 3, 5;
 }
 
 // Data that doesn't belong to a stream.
 message Metadata {
+  // Session identifier used for signed-out feed requests and interactions.
+  message SessionID {
+    string token = 1;
+    int64 expiry_time_ms = 2;
+  }
+
   // Token used to read or write to the same storage.
   bytes consistency_token = 1;
   // ID for the next pending action.
   int32 next_action_id = 2;
+  // The most recent session identifier.
+  SessionID session_id = 3;
 }
 
 // A set of StreamStructures that should be applied to a stream.

components/feed/core/proto/v2/wire/chrome_client_info.proto

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+package feedwire;
+
+option optimize_for = LITE_RUNTIME;
+
+// Information about the client performing the request, relevant only to Chrome
+// surfaces.
+message ChromeClientInfo {
+  // The signed-out session identifier (Zwieback) token, for clients which embed
+  // this information in-band instead of using an HTTP Cookie.
+  optional string session_id = 3;
+}

components/feed/core/proto/v2/wire/chrome_feed_response_metadata.proto

@@ -11,4 +11,5 @@ option optimize_for = LITE_RUNTIME;
 message ChromeFeedResponseMetadata {
   optional bool privacy_notice_fulfilled = 1;
   optional bool logging_enabled = 2;
+  optional string session_id = 3;
 }

components/feed/core/proto/v2/wire/client_info.proto

@@ -8,6 +8,7 @@ package feedwire;
 
 option optimize_for = LITE_RUNTIME;
 
+import "components/feed/core/proto/v2/wire/chrome_client_info.proto";
 import "components/feed/core/proto/v2/wire/display_info.proto";
 import "components/feed/core/proto/v2/wire/version.proto";
 
@@ -58,4 +59,8 @@ message ClientInfo {
   // this comes from GServices check-in which uses the SIM card MCC (mobile
   // country code), with fallback to IP geo lookup.
   optional string device_country = 9;
+
+  // Information about the client performing the request, relevant only to
+  // Chrome surfaces.
+  optional ChromeClientInfo chrome_client_info = 338478298;
 }

components/feed/core/v2/config.cc

@@ -76,6 +76,16 @@ void OverrideWithFinch(Config* config) {
           kInterestFeedV2, "upload_actions_on_enter_background",
           config->upload_actions_on_enter_background);
 
+  config->send_signed_out_session_logs =
+      base::GetFieldTrialParamByFeatureAsBool(
+          kInterestFeedV2, "send_signed_out_session_logs",
+          config->send_signed_out_session_logs);
+
+  config->session_id_max_age =
+      base::TimeDelta::FromDays(base::GetFieldTrialParamByFeatureAsInt(
+          kInterestFeedV2, "session_id_max_age_days",
+          config->session_id_max_age.InDays()));
+
   // Erase any capabilities with "enable_CAPABILITY = false" set.
   base::EraseIf(config->experimental_capabilities, CapabilityDisabled);
 }

components/feed/core/v2/config.h

@@ -38,6 +38,10 @@ struct Config {
   int load_more_trigger_lookahead = 5;
   // Whether to attempt uploading actions when Chrome is hidden.
   bool upload_actions_on_enter_background = true;
+  // Whether to send (pseudonymous) logs for signed-out sessions.
+  bool send_signed_out_session_logs = true;
+  // The max age of a signed-out session token.
+  base::TimeDelta session_id_max_age = base::TimeDelta::FromDays(30);
   // Set of optional capabilities included in requests. See
   // CreateFeedQueryRequest() for required capabilities.
   base::flat_set<feedwire::Capability> experimental_capabilities = {

components/feed/core/v2/feed_stream.cc

@@ -113,7 +113,7 @@ void FeedStream::Metadata::Populate(feedstore::Metadata metadata) {
   metadata_ = std::move(metadata);
 }
 
-std::string FeedStream::Metadata::GetConsistencyToken() const {
+const std::string& FeedStream::Metadata::GetConsistencyToken() const {
   return metadata_.consistency_token();
 }
 
@@ -122,6 +122,36 @@ void FeedStream::Metadata::SetConsistencyToken(std::string consistency_token) {
   store_->WriteMetadata(metadata_, base::DoNothing());
 }
 
+const std::string& FeedStream::Metadata::GetSessionIdToken() const {
+  return metadata_.session_id().token();
+}
+
+base::Time FeedStream::Metadata::GetSessionIdExpiryTime() const {
+  return base::Time::FromDeltaSinceWindowsEpoch(
+      base::TimeDelta::FromMilliseconds(
+          metadata_.session_id().expiry_time_ms()));
+}
+
+void FeedStream::Metadata::SetSessionId(std::string token,
+                                        base::Time expiry_time) {
+  feedstore::Metadata::SessionID* session_id = metadata_.mutable_session_id();
+  session_id->set_token(std::move(token));
+  session_id->set_expiry_time_ms(
+      expiry_time.ToDeltaSinceWindowsEpoch().InMilliseconds());
+  store_->WriteMetadata(metadata_, base::DoNothing());
+}
+
+void FeedStream::Metadata::MaybeUpdateSessionId(
+    base::Optional<std::string> token,
+    const base::Clock* clock) {
+  if (token && metadata_.session_id().token() != *token) {
+    base::Time expiry_time =
+        token->empty() ? base::Time()
+                       : clock->Now() + GetFeedConfig().session_id_max_age;
+    SetSessionId(*token, expiry_time);
+  }
+}
+
 LocalActionId FeedStream::Metadata::GetNextActionId() {
   uint32_t id = metadata_.next_action_id();
   // Never use 0, as that's an invalid LocalActionId.
@@ -239,7 +269,13 @@ bool FeedStream::IsActivityLoggingEnabled() const {
 
 void FeedStream::UpdateIsActivityLoggingEnabled() {
   is_activity_logging_enabled_ =
-      model_ && model_->signed_in() && model_->logging_enabled();
+      model_ &&
+      ((model_->signed_in() && model_->logging_enabled()) ||
+       (!model_->signed_in() && GetFeedConfig().send_signed_out_session_logs));
+}
+
+std::string FeedStream::GetSessionId() const {
+  return GetMetadata()->GetSessionIdToken();
 }
 
 void FeedStream::AttachSurface(SurfaceInterface* surface) {
@@ -302,7 +338,7 @@ bool FeedStream::IsArticlesListVisible() {
   return profile_prefs_->GetBoolean(prefs::kArticlesListVisible);
 }
 
-std::string FeedStream::GetClientInstanceId() {
+std::string FeedStream::GetClientInstanceId() const {
   return prefs::GetClientInstanceId(*profile_prefs_);
 }
 
@@ -571,14 +607,38 @@ bool FeedStream::ShouldForceSignedOutFeedQueryRequest() const {
   return base::TimeTicks::Now() < signed_out_refreshes_until_;
 }
 
-RequestMetadata FeedStream::GetRequestMetadata() {
+RequestMetadata FeedStream::GetRequestMetadata(bool is_for_next_page) const {
   RequestMetadata result;
   result.chrome_info = chrome_info_;
   result.display_metrics = delegate_->GetDisplayMetrics();
   result.language_tag = delegate_->GetLanguageTag();
-  result.client_instance_id = GetClientInstanceId();
   result.notice_card_acknowledged =
       notice_card_tracker_.HasAcknowledgedNoticeCard();
+
+  if (is_for_next_page) {
+    // If we are continuing an existing feed, use whatever session continuity
+    // mechanism is currently associated with the stream: client-instance-id
+    // for signed-in feed, session_id token for signed-out.
+    DCHECK(model_);
+    if (model_->signed_in()) {
+      result.client_instance_id = GetClientInstanceId();
+    } else {
+      result.session_id = GetMetadata()->GetSessionIdToken();
+    }
+  } else {
+    // The request is for the first page of the feed. Use client_instance_id
+    // for signed in requests and session_id token (if any, and not expired)
+    // for signed-out.
+    if (delegate_->IsSignedIn() && !ShouldForceSignedOutFeedQueryRequest()) {
+      result.client_instance_id = GetClientInstanceId();
+    } else if (!GetMetadata()->GetSessionIdToken().empty() &&
+               GetMetadata()->GetSessionIdExpiryTime() > clock_->Now()) {
+      result.session_id = GetMetadata()->GetSessionIdToken();
+    }
+  }
+
+  DCHECK(result.session_id.empty() || result.client_instance_id.empty());
+
   return result;
 }
 
@@ -739,6 +799,7 @@ void FeedStream::ReportSliceViewed(SurfaceId surface_id,
     metrics_reporter_->ContentSliceViewed(surface_id, index);
   }
 }
+// TODO(crbug/1147237): Rename this method and related members?
 bool FeedStream::CanUploadActions() const {
   return can_upload_actions_with_notice_card_ ||
          !prefs::GetLastFetchHadNoticeCard(*profile_prefs_);

components/feed/core/v2/feed_stream.h

@@ -92,9 +92,15 @@ class FeedStream : public FeedStreamApi,
 
     void Populate(feedstore::Metadata metadata);
 
-    std::string GetConsistencyToken() const;
+    const std::string& GetConsistencyToken() const;
     void SetConsistencyToken(std::string consistency_token);
 
+    const std::string& GetSessionIdToken() const;
+    base::Time GetSessionIdExpiryTime() const;
+    void SetSessionId(std::string token, base::Time expiry_time);
+    void MaybeUpdateSessionId(base::Optional<std::string> token,
+                              const base::Clock* clock);
+
     LocalActionId GetNextActionId();
 
    private:
@@ -125,11 +131,12 @@ class FeedStream : public FeedStreamApi,
   // FeedStreamApi.
 
   bool IsActivityLoggingEnabled() const override;
+  std::string GetSessionId() const override;
   void AttachSurface(SurfaceInterface*) override;
   void DetachSurface(SurfaceInterface*) override;
   void SetArticlesListVisible(bool is_visible) override;
   bool IsArticlesListVisible() override;
-  std::string GetClientInstanceId() override;
+  std::string GetClientInstanceId() const override;
   void ExecuteRefreshTask() override;
   ImageFetchId FetchImage(
       const GURL& url,
@@ -215,6 +222,7 @@ class FeedStream : public FeedStreamApi,
   FeedStore* GetStore() { return store_; }
   RequestThrottler* GetRequestThrottler() { return &request_throttler_; }
   Metadata* GetMetadata() { return &metadata_; }
+  const Metadata* GetMetadata() const { return &metadata_; }
   MetricsReporter* GetMetricsReporter() const { return metrics_reporter_; }
 
   // Returns the time of the last content fetch.
@@ -256,7 +264,7 @@ class FeedStream : public FeedStreamApi,
 
   const base::Clock* GetClock() const { return clock_; }
   const base::TickClock* GetTickClock() const { return tick_clock_; }
-  RequestMetadata GetRequestMetadata();
+  RequestMetadata GetRequestMetadata(bool is_for_next_page) const;
 
   const WireResponseTranslator* GetWireResponseTranslator() const {
     return wire_response_translator_;

components/feed/core/v2/notice_card_tracker.cc

@@ -36,7 +36,7 @@ void NoticeCardTracker::OnOpenAction(int index) {
   MaybeUpdateNoticeCardClicksCount(index);
 }
 
-bool NoticeCardTracker::HasAcknowledgedNoticeCard() {
+bool NoticeCardTracker::HasAcknowledgedNoticeCard() const {
   constexpr char kNoticeCardViewsCountThresholdParamName[] =
       "notice-card-views-count-threshold";
   constexpr char kNoticeCardClicksCountThresholdParamName[] =

components/feed/core/v2/notice_card_tracker.h

@@ -27,7 +27,7 @@ class NoticeCardTracker {
 
   // Indicates whether there were enough views or clicks done on the notice
   // card to consider it as acknowledged by the user.
-  bool HasAcknowledgedNoticeCard();
+  bool HasAcknowledgedNoticeCard() const;
 
  private:
   bool HasNoticeCardActionsCountPrerequisites(int index);

components/feed/core/v2/proto_util.cc

@@ -13,6 +13,7 @@
 #include "build/build_config.h"
 #include "components/feed/core/proto/v2/store.pb.h"
 #include "components/feed/core/proto/v2/wire/capability.pb.h"
+#include "components/feed/core/proto/v2/wire/chrome_client_info.pb.h"
 #include "components/feed/core/proto/v2/wire/feed_request.pb.h"
 #include "components/feed/core/proto/v2/wire/request.pb.h"
 #include "components/feed/core/v2/config.h"
@@ -125,9 +126,15 @@ feedwire::Request CreateFeedQueryRequest(
   *feed_request.mutable_client_info() = CreateClientInfo(request_metadata);
   feedwire::FeedQuery& query = *feed_request.mutable_feed_query();
   query.set_reason(request_reason);
-  if (!consistency_token.empty()) {
+
+  // |consistency_token|, for action reporting, is only applicable to signed-in
+  // requests. The presence of |client_instance_id|, also signed-in only, can be
+  // used a proxy for checking if we're creating a signed-in request.
+  if (!consistency_token.empty() &&
+      !request_metadata.client_instance_id.empty()) {
     feed_request.mutable_consistency_token()->set_token(consistency_token);
   }
+
   if (!next_page_token.empty()) {
     DCHECK_EQ(request_reason, feedwire::FeedQuery::NEXT_PAGE_SCROLL);
     query.mutable_next_page_token()
@@ -187,7 +194,6 @@ bool CompareContent(const feedstore::Content& a, const feedstore::Content& b) {
 
 feedwire::ClientInfo CreateClientInfo(const RequestMetadata& request_metadata) {
   feedwire::ClientInfo client_info;
-  client_info.set_client_instance_id(request_metadata.client_instance_id);
 
   feedwire::DisplayInfo& display_info = *client_info.add_display_info();
   display_info.set_screen_density(request_metadata.display_metrics.density);
@@ -207,6 +213,19 @@ feedwire::ClientInfo CreateClientInfo(const RequestMetadata& request_metadata) {
   *client_info.mutable_platform_version() = GetPlatformVersionMessage();
   *client_info.mutable_app_version() =
       GetAppVersionMessage(request_metadata.chrome_info);
+
+  // client_instance_id and session_id should not both be set at the same time.
+  DCHECK(request_metadata.client_instance_id.empty() ||
+         request_metadata.session_id.empty());
+
+  // Populate client_instance_id, session_id, or neither.
+  if (!request_metadata.client_instance_id.empty()) {
+    client_info.set_client_instance_id(request_metadata.client_instance_id);
+  } else if (!request_metadata.session_id.empty()) {
+    client_info.mutable_chrome_client_info()->set_session_id(
+        request_metadata.session_id);
+  }
+
   return client_info;
 }
 

components/feed/core/v2/protocol_translator.cc

@@ -306,6 +306,18 @@ RefreshResponseData TranslateWireResponse(
   result->stream_data.set_privacy_notice_fulfilled(
       response_metadata.privacy_notice_fulfilled());
 
+  base::Optional<std::string> session_id = base::nullopt;
+  if (was_signed_in_request) {
+    // Signed-in requests don't use session_id tokens; set an empty value to
+    // ensure that there are no old session_id tokens left hanging around.
+    session_id = std::string();
+  } else if (response_metadata.has_session_id()) {
+    // Signed-out requests can set a new session token; otherwise, we leave
+    // the default base::nullopt value to keep whatever token is already in
+    // play.
+    session_id = response_metadata.session_id();
+  }
+
   MetricsReporter::ActivityLoggingEnabled(response_metadata.logging_enabled());
   MetricsReporter::NoticeCardFulfilledObsolete(
       response_metadata.privacy_notice_fulfilled());
@@ -313,6 +325,7 @@ RefreshResponseData TranslateWireResponse(
   RefreshResponseData response_data;
   response_data.model_update_request = std::move(result);
   response_data.request_schedule = std::move(global_data.request_schedule);
+  response_data.session_id = std::move(session_id);
 
   return response_data;
 }

components/feed/core/v2/protocol_translator.h

@@ -64,6 +64,9 @@ struct RefreshResponseData {
 
   // Server-defined request schedule, if provided.
   base::Optional<RequestSchedule> request_schedule;
+
+  // Server-defined session id token, if provided.
+  base::Optional<std::string> session_id;
 };
 
 base::Optional<feedstore::DataOperation> TranslateDataOperation(

components/feed/core/v2/public/feed_stream_api.h

@@ -63,9 +63,14 @@ class FeedStreamApi {
   // as the feed is refreshed or the user signs in/out.
   virtual bool IsActivityLoggingEnabled() const = 0;
 
-  // Returns the client_instance_id. This value is reset whenever the feed
-  // stream is cleared (on sign-in, sign-out, and some data clear events).
-  virtual std::string GetClientInstanceId() = 0;
+  // Returns the signed-in client_instance_id. This value is reset whenever the
+  // feed stream is cleared (on sign-in, sign-out, and some data clear events).
+  virtual std::string GetClientInstanceId() const = 0;
+
+  // Returns the client's signed-out session id. This value is reset whenever
+  // the feed stream is cleared (on sign-in, sign-out, and some data clear
+  // events).
+  virtual std::string GetSessionId() const = 0;
 
   // Invoked by RefreshTaskScheduler's scheduled task.
   virtual void ExecuteRefreshTask() = 0;

components/feed/core/v2/tasks/load_more_task.cc

@@ -68,7 +68,7 @@ void LoadMoreTask::UploadActionsComplete(UploadActionsTask::Result result) {
   fetch_start_time_ = stream_->GetTickClock()->NowTicks();
   stream_->GetNetwork()->SendQueryRequest(
       CreateFeedQueryLoadMoreRequest(
-          stream_->GetRequestMetadata(),
+          stream_->GetRequestMetadata(/*is_for_next_page=*/true),
           stream_->GetMetadata()->GetConsistencyToken(),
           stream_->GetModel()->GetNextPageToken()),
       force_signed_out_request,
@@ -94,6 +94,10 @@ void LoadMoreTask::QueryRequestComplete(
 
   loaded_new_content_from_network_ =
       !translated_response.model_update_request->stream_structures.empty();
+
+  stream_->GetMetadata()->MaybeUpdateSessionId(translated_response.session_id,
+                                               stream_->GetClock());
+
   model->Update(std::move(translated_response.model_update_request));
 
   if (translated_response.request_schedule)

components/feed/core/v2/tasks/load_stream_from_store_task.cc

@@ -126,8 +126,6 @@ void LoadStreamFromStoreTask::Complete(LoadStreamStatus status) {
   if (status == LoadStreamStatus::kLoadedFromStore &&
       load_type_ == LoadType::kFullLoad) {
     task_result.update_request = std::move(update_request_);
-  } else {
-    task_result.consistency_token = consistency_token_;
   }
   std::move(result_callback_).Run(std::move(task_result));
   TaskComplete();

components/feed/core/v2/tasks/load_stream_from_store_task.h

@@ -76,7 +76,6 @@ class LoadStreamFromStoreTask : public offline_pages::Task {
 
   // Data to be stuffed into the Result when the task is complete.
   std::unique_ptr<StreamModelUpdateRequest> update_request_;
-  std::string consistency_token_;
   std::vector<feedstore::StoredAction> pending_actions_;
 
   base::WeakPtrFactory<LoadStreamFromStoreTask> weak_ptr_factory_{this};

components/feed/core/v2/tasks/load_stream_task.cc

@@ -123,7 +123,8 @@ void LoadStreamTask::UploadActionsComplete(UploadActionsTask::Result result) {
   latencies_->StepComplete(LoadLatencyTimes::kUploadActions);
   stream_->GetNetwork()->SendQueryRequest(
       CreateFeedQueryRefreshRequest(
-          GetRequestReason(load_type_), stream_->GetRequestMetadata(),
+          GetRequestReason(load_type_),
+          stream_->GetRequestMetadata(/*is_for_next_page=*/false),
           stream_->GetMetadata()->GetConsistencyToken()),
       force_signed_out_request,
       base::BindOnce(&LoadStreamTask::QueryRequestComplete, GetWeakPtr()));
@@ -167,6 +168,9 @@ void LoadStreamTask::QueryRequestComplete(
   stream_->SetLastStreamLoadHadNoticeCard(isNoticeCardFulfilled);
   MetricsReporter::NoticeCardFulfilled(isNoticeCardFulfilled);
 
+  stream_->GetMetadata()->MaybeUpdateSessionId(response_data.session_id,
+                                               stream_->GetClock());
+
   if (load_type_ != LoadType::kBackgroundRefresh) {
     auto model = std::make_unique<StreamModel>();
     model->Update(std::move(response_data.model_update_request));

components/feed/core/v2/test/stream_builder.cc

@@ -158,12 +158,13 @@ std::vector<feedstore::DataOperation> MakeTypicalStreamOperations() {
   };
 }
 
-std::unique_ptr<StreamModelUpdateRequest> MakeTypicalInitialModelState(
-    int first_cluster_id,
-    base::Time last_added_time,
-    bool signed_in,
-    bool logging_enabled,
-    bool privacy_notice_fulfilled) {
+StreamModelUpdateRequestGenerator::StreamModelUpdateRequestGenerator() =
+    default;
+StreamModelUpdateRequestGenerator::~StreamModelUpdateRequestGenerator() =
+    default;
+
+std::unique_ptr<StreamModelUpdateRequest>
+StreamModelUpdateRequestGenerator::MakeFirstPage(int first_cluster_id) const {
   auto initial_update = std::make_unique<StreamModelUpdateRequest>();
   const int i = first_cluster_id;
   const int j = first_cluster_id + 1;
@@ -191,12 +192,8 @@ std::unique_ptr<StreamModelUpdateRequest> MakeTypicalInitialModelState(
   return initial_update;
 }
 
-std::unique_ptr<StreamModelUpdateRequest> MakeTypicalNextPageState(
-    int page_number,
-    base::Time last_added_time,
-    bool signed_in,
-    bool logging_enabled,
-    bool privacy_notice_fulfilled) {
+std::unique_ptr<StreamModelUpdateRequest>
+StreamModelUpdateRequestGenerator::MakeNextPage(int page_number) const {
   auto initial_update = std::make_unique<StreamModelUpdateRequest>();
   initial_update->source =
       StreamModelUpdateRequest::Source::kInitialLoadFromStore;
@@ -224,4 +221,32 @@ std::unique_ptr<StreamModelUpdateRequest> MakeTypicalNextPageState(
   return initial_update;
 }
 
+std::unique_ptr<StreamModelUpdateRequest> MakeTypicalInitialModelState(
+    int first_cluster_id,
+    base::Time last_added_time,
+    bool signed_in,
+    bool logging_enabled,
+    bool privacy_notice_fulfilled) {
+  StreamModelUpdateRequestGenerator generator;
+  generator.last_added_time = last_added_time;
+  generator.signed_in = signed_in;
+  generator.logging_enabled = logging_enabled;
+  generator.privacy_notice_fulfilled = privacy_notice_fulfilled;
+  return generator.MakeFirstPage(first_cluster_id);
+}
+
+std::unique_ptr<StreamModelUpdateRequest> MakeTypicalNextPageState(
+    int page_number,
+    base::Time last_added_time,
+    bool signed_in,
+    bool logging_enabled,
+    bool privacy_notice_fulfilled) {
+  StreamModelUpdateRequestGenerator generator;
+  generator.last_added_time = last_added_time;
+  generator.signed_in = signed_in;
+  generator.logging_enabled = logging_enabled;
+  generator.privacy_notice_fulfilled = privacy_notice_fulfilled;
+  return generator.MakeNextPage(page_number);
+}
+
 }  // namespace feed

components/feed/core/v2/test/stream_builder.h

@@ -12,6 +12,7 @@
 #include "base/time/time.h"
 #include "components/feed/core/proto/v2/store.pb.h"
 #include "components/feed/core/v2/proto_util.h"
+#include "components/feed/core/v2/protocol_translator.h"
 #include "components/feed/core/v2/types.h"
 
 // Functions that help build a feedstore::StreamStructure for testing.
@@ -43,6 +44,25 @@ feedstore::Record MakeRecord(
 feedstore::Record MakeRecord(feedstore::StreamSharedState shared_state);
 feedstore::Record MakeRecord(feedstore::StreamData stream_data);
 
+// Helper structure to configure and return RefreshResponseData and
+// StreamModelUpdateRequest objects denoting typical initial and next page
+// refresh response payloads.
+struct StreamModelUpdateRequestGenerator {
+  base::Time last_added_time = kTestTimeEpoch;
+  bool signed_in = true;
+  bool logging_enabled = true;
+  bool privacy_notice_fulfilled = true;
+
+  StreamModelUpdateRequestGenerator();
+  ~StreamModelUpdateRequestGenerator();
+
+  std::unique_ptr<StreamModelUpdateRequest> MakeFirstPage(
+      int first_cluster_id = 0) const;
+
+  std::unique_ptr<StreamModelUpdateRequest> MakeNextPage(
+      int page_number = 2) const;
+};
+
 // Returns data operations to create a typical stream:
 // Root
 // |-Cluster 0

components/feed/core/v2/types.h

@@ -39,6 +39,7 @@ struct RequestMetadata {
   ChromeInfo chrome_info;
   std::string language_tag;
   std::string client_instance_id;
+  std::string session_id;
   DisplayMetrics display_metrics;
   bool notice_card_acknowledged = false;
 };