Add |SetImageDownloadLimit| to ImageFetcher to limit downloaded bytes

components/image_fetcher/core/image_data_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_IMAGE_FETCHER_CORE_IMAGE_DATA_FETCHER_H_
 #define COMPONENTS_IMAGE_FETCHER_CORE_IMAGE_DATA_FETCHER_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 24 matching lines @@
 
   using DataUseServiceName = data_use_measurement::DataUseUserData::ServiceName;
 
   explicit ImageDataFetcher(
       net::URLRequestContextGetter* url_request_context_getter);
   ~ImageDataFetcher() override;
 
   // Sets a service name against which to track data usage.
   void SetDataUseServiceName(DataUseServiceName data_use_service_name);
 
+  // Sets an upper limit for image downloads that is by default disabled.

[Marc Treib, 2017/03/27 13:16:42]

nit: Remove "that is by default disabled", IMO that doesn't belong on the
setter.

[fhorschig, 2017/03/27 14:33:43]

Done.

+  // Setting |max_download_bytes| to a negative value will disable the limit.

[Marc Treib, 2017/03/27 13:16:42]

Hm. Make it a base::Optional<int64_t> instead? IMO that's clearer than the
negative values hack.

[fhorschig, 2017/03/27 14:33:43]

Done.

+  // Already running downloads are immediately affected.
+  void SetImageDownloadLimit(int64_t max_download_bytes) {
+    max_download_bytes_ = max_download_bytes < 0 ? 0 : max_download_bytes;

[Marc Treib, 2017/03/27 13:16:42]

Move implementation to .cc file?

[fhorschig, 2017/03/27 14:33:43]

Done.

+  }
+
   // Fetches the raw image bytes from the given |image_url| and calls the given
   // |callback|. The callback is run even if fetching the URL fails. In case
   // of an error an empty string is passed to the callback.
   void FetchImageData(const GURL& image_url,
                       const ImageDataFetcherCallback& callback);
 
   // Like above, but lets the caller set a referrer.
   void FetchImageData(const GURL& image_url,
                       const ImageDataFetcherCallback& callback,
                       const std::string& referrer,
                       net::URLRequest::ReferrerPolicy referrer_policy);
 
  private:
   struct ImageDataFetcherRequest;
 
-  // Method inherited from URLFetcherDelegate
+  // Methods inherited from URLFetcherDelegate
   void OnURLFetchComplete(const net::URLFetcher* source) override;
+  void OnURLFetchDownloadProgress(const net::URLFetcher* source,
+                                  int64_t current,
+                                  int64_t total,
+                                  int64_t current_network_bytes) override;
 
   // All active image url requests.
   std::map<const net::URLFetcher*, std::unique_ptr<ImageDataFetcherRequest>>
       pending_requests_;
 
   scoped_refptr<net::URLRequestContextGetter> url_request_context_getter_;
 
   DataUseServiceName data_use_service_name_;
 
   // The next ID to use for a newly created URLFetcher. Each URLFetcher gets an
   // id when it is created. The |url_fetcher_id_| is incremented by one for each
   // newly created URLFetcher. The URLFetcher ID can be used during testing to
   // get individual URLFetchers and modify their state. Outside of tests this ID
   // is not used.
   int next_url_fetcher_id_;
 
+  // Running requests exceeding this limit will be canceled immediately. By

[Marc Treib, 2017/03/27 13:16:42]

Upper limit for the number of bytes to download per image.
(The "running requests..." part is really secondary)

[fhorschig, 2017/03/27 14:33:43]

Done.

+  // default negative and therefore disabled.
+  int64_t max_download_bytes_;
+
   DISALLOW_COPY_AND_ASSIGN(ImageDataFetcher);
 };
 
 }  // namespace image_fetcher
 
 #endif  // COMPONENTS_IMAGE_FETCHER_CORE_IMAGE_DATA_FETCHER_H_