Integrate throttling logic into AffiliationBackend.

components/password_manager/core/browser/affiliation_backend.cc

Index: components/password_manager/core/browser/affiliation_backend.cc
diff --git a/components/password_manager/core/browser/affiliation_backend.cc b/components/password_manager/core/browser/affiliation_backend.cc
index ec937608af23d26e17d6fdf7bce07e4672aea742..5b2c637beb046053f8284ef0a4b124068d858a6d 100644
--- a/components/password_manager/core/browser/affiliation_backend.cc
+++ b/components/password_manager/core/browser/affiliation_backend.cc
@@ -9,12 +9,12 @@
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
-#include "base/task_runner.h"
-#include "base/thread_task_runner_handle.h"
 #include "base/threading/thread_checker.h"
 #include "base/time/clock.h"
+#include "base/time/tick_clock.h"
 #include "base/time/time.h"
 #include "components/password_manager/core/browser/affiliation_database.h"
+#include "components/password_manager/core/browser/affiliation_fetch_throttler.h"
 #include "components/password_manager/core/browser/affiliation_fetcher.h"
 #include "components/password_manager/core/browser/facet_manager.h"
 #include "net/url_request/url_request_context_getter.h"
@@ -23,9 +23,13 @@ namespace password_manager {
 
 AffiliationBackend::AffiliationBackend(
     const scoped_refptr<net::URLRequestContextGetter>& request_context_getter,
-    scoped_ptr<base::Clock> time_source)
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    scoped_ptr<base::Clock> time_source,
+    scoped_ptr<base::TickClock> time_tick_source)
     : request_context_getter_(request_context_getter),
+      task_runner_(task_runner),
       clock_(time_source.Pass()),
+      tick_clock_(time_tick_source.Pass()),
       weak_ptr_factory_(this) {
   DCHECK_LT(base::Time(), clock_->Now());
 }
@@ -35,6 +39,11 @@ AffiliationBackend::~AffiliationBackend() {
 
 void AffiliationBackend::Initialize(const base::FilePath& db_path) {
   thread_checker_.reset(new base::ThreadChecker);
+
+  DCHECK(!throttler_);
+  throttler_.reset(
+      new AffiliationFetchThrottler(this, task_runner_, tick_clock_.get()));
+
   cache_.reset(new AffiliationDatabase());
   if (!cache_->Init(db_path)) {
     // TODO(engedy): Implement this. crbug.com/437865.
@@ -99,20 +108,6 @@ FacetManager* AffiliationBackend::GetOrCreateFacetManager(
   return facet_managers_.get(facet_uri);
 }
 
-void AffiliationBackend::SendNetworkRequest() {
-  DCHECK(!fetcher_);
-
-  std::vector<FacetURI> requested_facet_uris;
-  for (const auto& facet_manager_pair : facet_managers_) {
-    if (facet_manager_pair.second->DoesRequireFetch())
-      requested_facet_uris.push_back(facet_manager_pair.first);
-  }
-  DCHECK(!requested_facet_uris.empty());
-  fetcher_.reset(AffiliationFetcher::Create(request_context_getter_.get(),
-                                            requested_facet_uris, this));
-  fetcher_->StartRequest();
-}
-
 void AffiliationBackend::OnSendNotification(const FacetURI& facet_uri) {
   DCHECK(thread_checker_ && thread_checker_->CalledOnValidThread());
 
@@ -132,17 +127,14 @@ bool AffiliationBackend::ReadAffiliationsFromDatabase(
 }
 
 void AffiliationBackend::SignalNeedNetworkRequest() {
-  // TODO(engedy): Add more sophisticated throttling logic. crbug.com/437865.
-  if (fetcher_)
-    return;
-  SendNetworkRequest();
+  throttler_->SignalNetworkRequestNeeded();
 }
 
 void AffiliationBackend::RequestNotificationAtTime(const FacetURI& facet_uri,
                                                    base::Time time) {
   // TODO(engedy): Avoid spamming the task runner; only ever schedule the first
   // callback. crbug.com/437865.
-  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+  task_runner_->PostDelayedTask(
       FROM_HERE, base::Bind(&AffiliationBackend::OnSendNotification,
                             weak_ptr_factory_.GetWeakPtr(), facet_uri),
       time - clock_->Now());
@@ -151,7 +143,9 @@ void AffiliationBackend::RequestNotificationAtTime(const FacetURI& facet_uri,
 void AffiliationBackend::OnFetchSucceeded(
     scoped_ptr<AffiliationFetcherDelegate::Result> result) {
   DCHECK(thread_checker_ && thread_checker_->CalledOnValidThread());
+
   fetcher_.reset();
+  throttler_->InformOfNetworkRequestComplete(true);
 
   for (const AffiliatedFacets& affiliated_facets : *result) {
     AffiliatedFacetsWithUpdateTime affiliation;
@@ -182,7 +176,7 @@ void AffiliationBackend::OnFetchSucceeded(
   // requests came in while the current fetch was in flight.
   for (const auto& facet_manager_pair : facet_managers_) {
     if (facet_manager_pair.second->DoesRequireFetch()) {
-      SendNetworkRequest();
+      throttler_->SignalNetworkRequestNeeded();
       return;
     }
   }
@@ -191,15 +185,46 @@ void AffiliationBackend::OnFetchSucceeded(
 void AffiliationBackend::OnFetchFailed() {
   DCHECK(thread_checker_ && thread_checker_->CalledOnValidThread());
 
-  // TODO(engedy): Implement this. crbug.com/437865.
-  NOTIMPLEMENTED();
+  fetcher_.reset();
+  throttler_->InformOfNetworkRequestComplete(false);
+
+  // Trigger a retry if a fetch is still needed.
+  for (const auto& facet_manager_pair : facet_managers_) {
+    if (facet_manager_pair.second->DoesRequireFetch()) {
+      throttler_->SignalNetworkRequestNeeded();
+      return;
+    }
+  }
 }
 
 void AffiliationBackend::OnMalformedResponse() {
   DCHECK(thread_checker_ && thread_checker_->CalledOnValidThread());
 
-  // TODO(engedy): Implement this. crbug.com/437865.
-  NOTIMPLEMENTED();
+  // TODO(engedy): Potentially handle this case differently. crbug.com/437865.
+  OnFetchFailed();
+}
+
+bool AffiliationBackend::OnCanSendNetworkRequest() {
+  DCHECK(!fetcher_);
+  std::vector<FacetURI> requested_facet_uris;
+  for (const auto& facet_manager_pair : facet_managers_) {
+    if (facet_manager_pair.second->DoesRequireFetch())
+      requested_facet_uris.push_back(facet_manager_pair.first);
+  }
+
+  // In case a request is no longer needed, return false to indicate this.
+  if (requested_facet_uris.empty())
+    return false;
+
+  fetcher_.reset(AffiliationFetcher::Create(request_context_getter_.get(),
+                                            requested_facet_uris, this));
+  fetcher_->StartRequest();
+  return true;
+}
+
+void AffiliationBackend::SetThrottlerForTesting(
+    scoped_ptr<AffiliationFetchThrottler> throttler) {
+  throttler_ = throttler.Pass();
 }
 
 }  // namespace password_manager