Adding a request counter to the snippets fetcher.

components/ntp_snippets/ntp_snippets_fetcher.h

 // Copyright 2016 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.
 
 #ifndef COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_FETCHER_H_
 #define COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_FETCHER_H_
 
 #include <memory>
 #include <set>
 #include <string>
+#include <utility>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "base/optional.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
 #include "components/ntp_snippets/ntp_snippet.h"
+#include "components/ntp_snippets/request_throttler.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "net/url_request/url_request_context_getter.h"
 
+class PrefService;
 class SigninManagerBase;
 
 namespace base {
 class Value;
 }  // namespace base
 
 namespace net {
 class HttpRequestHeaders;
 }  // namespace net
 
@@ skipping 36 matching lines @@
   enum class Personalization {
     kPersonal,
     kNonPersonal,
     kBoth
   };
 
   NTPSnippetsFetcher(
       SigninManagerBase* signin_manager,
       OAuth2TokenService* oauth2_token_service,
       scoped_refptr<net::URLRequestContextGetter> url_request_context_getter,
+      PrefService* pref_service,
       const ParseJSONCallback& parse_json_callback,
       bool is_stable_channel);
   ~NTPSnippetsFetcher() override;
 
   // Set a callback that is called when a new set of snippets are downloaded,
   // overriding any previously set callback.
   void SetCallback(const SnippetsAvailableCallback& callback);
 
   // Fetches snippets from the server. |hosts| restricts the results to a set of
   // hosts, e.g. "www.google.com". An empty host set produces an error.
   //
   // If an ongoing fetch exists, it will be cancelled and a new one started,
   // without triggering an additional callback (i.e. not noticeable by
   // subscriber of SetCallback()).
+  //
+  // Fetches snippets only if the daily quota not exceeded, unless
+  // |force_request| is set to true. Use force only for user-initiated fetches.
   void FetchSnippetsFromHosts(const std::set<std::string>& hosts,
                               const std::string& language_code,
-                              int count);
+                              int count,
+                              bool force_request);
 
   // Debug string representing the status/result of the last fetch attempt.
   const std::string& last_status() const { return last_status_; }
 
   // Returns the last JSON fetched from the server.
   const std::string& last_json() const {
     return last_fetch_json_;
   }
 
   // Returns the personalization setting of the fetcher.
@@ skipping 104 matching lines @@
   bool is_stable_channel_;
 
   // The variant of the fetching to use, loaded from variation parameters.
   Personalization personalization_;
   // Should we apply host restriction? It is loaded from variation parameters.
   bool use_host_restriction_;
 
   // Allow for an injectable tick clock for testing.
   std::unique_ptr<base::TickClock> tick_clock_;
 
+  // Request throttler for limiting requests.
+  RequestThrottler request_throttler_;
+
   base::WeakPtrFactory<NTPSnippetsFetcher> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NTPSnippetsFetcher);
 };
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_FETCHER_H_