Add support for subresource request fallback in AppCache for the network service..

content/browser/appcache/appcache_url_loader_job.h

 // Copyright (c) 2017 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 CONTENT_BROWSER_APPCACHE_APPCACHE_URL_LOADER_JOB_H_
 #define CONTENT_BROWSER_APPCACHE_APPCACHE_URL_LOADER_JOB_H_
 
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "content/browser/appcache/appcache_entry.h"
 #include "content/browser/appcache/appcache_job.h"
 #include "content/browser/appcache/appcache_request_handler.h"
 #include "content/browser/appcache/appcache_response.h"
 #include "content/browser/appcache/appcache_storage.h"
 #include "content/browser/loader/url_loader_request_handler.h"
 #include "content/common/content_export.h"
 #include "content/public/common/resource_request.h"
 #include "content/public/common/url_loader.mojom.h"
 #include "mojo/public/cpp/bindings/associated_binding.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/public/cpp/system/data_pipe.h"
 
 namespace content {
 
 class AppCacheRequest;
+class AppCacheURLLoaderRequest;
 class NetToMojoPendingBuffer;
 class URLLoaderFactoryGetter;
-struct SubresourceLoadInfo;
 
 // Holds information about the subresource load request like the routing id,
 // request id, the client pointer, etc.
 struct SubresourceLoadInfo {
   SubresourceLoadInfo();
   ~SubresourceLoadInfo();
 
   mojom::URLLoaderAssociatedRequest url_loader_request;
   int32_t routing_id;
   int32_t request_id;
   uint32_t options;
   ResourceRequest request;
   mojom::URLLoaderClientPtr client;
   net::MutableNetworkTrafficAnnotationTag traffic_annotation;
 };
 
 // AppCacheJob wrapper for a mojom::URLLoader implementation which returns
 // responses stored in the AppCache.
 class CONTENT_EXPORT AppCacheURLLoaderJob : public AppCacheJob,
                                             public AppCacheStorage::Delegate,
-                                            public mojom::URLLoader {
+                                            public mojom::URLLoader,
+                                            public mojom::URLLoaderClient {
  public:
   ~AppCacheURLLoaderJob() override;
 
   // Sets up the bindings.
   void Start(mojom::URLLoaderRequest request, mojom::URLLoaderClientPtr client);
 
   // AppCacheJob overrides.
   void Kill() override;
   bool IsStarted() const override;
   void DeliverAppCachedResponse(const GURL& manifest_url,
                                 int64_t cache_id,
                                 const AppCacheEntry& entry,
                                 bool is_fallback) override;
   void DeliverNetworkResponse() override;
   void DeliverErrorResponse() override;
   const GURL& GetURL() const override;
   AppCacheURLLoaderJob* AsURLLoaderJob() override;
 
   // mojom::URLLoader implementation:
   void FollowRedirect() override;
   void SetPriority(net::RequestPriority priority,
                    int32_t intra_priority_value) override;
 
+  // mojom::URLLoaderClient implementation.
+  // These methods are called by the network loader for subresource requests
+  // which go to the network. We serve fallback content in these methods
+  // if applicable.
+  void OnReceiveResponse(const ResourceResponseHead& response_head,
+                         const base::Optional<net::SSLInfo>& ssl_info,
+                         mojom::DownloadedTempFilePtr downloaded_file) override;
+  void OnReceiveRedirect(const net::RedirectInfo& redirect_info,
+                         const ResourceResponseHead& response_head) override;
+  void OnDataDownloaded(int64_t data_len, int64_t encoded_data_len) override;
+  void OnUploadProgress(int64_t current_position,
+                        int64_t total_size,
+                        OnUploadProgressCallback ack_callback) override;
+  void OnReceiveCachedMetadata(const std::vector<uint8_t>& data) override;
+  void OnTransferSizeUpdated(int32_t transfer_size_diff) override;
+  void OnStartLoadingResponseBody(
+      mojo::ScopedDataPipeConsumerHandle body) override;
+  void OnComplete(const ResourceRequestCompletionStatus& status) override;
+
   void set_main_resource_loader_callback(LoaderCallback callback) {
     main_resource_loader_callback_ = std::move(callback);
   }
 
   // Subresource request load information is passed in the
   // |subresource_load_info| parameter. This includes the request id, the
   // client pointer, etc.
   // |default_url_loader| is used to retrieve the network loader for requests
   // intended to be sent to the network.
   void SetSubresourceLoadInfo(
       std::unique_ptr<SubresourceLoadInfo> subresource_load_info,
       URLLoaderFactoryGetter* default_url_loader);
 
   // Ownership of the |handler| is transferred to us via this call. This is
   // only for subresource requests.
   void set_request_handler(std::unique_ptr<AppCacheRequestHandler> handler) {
     sub_resource_handler_ = std::move(handler);
   }
 
  protected:
   // AppCacheJob::Create() creates this instance.
   friend class AppCacheJob;
 
   AppCacheURLLoaderJob(const ResourceRequest& request,
+                       AppCacheURLLoaderRequest* url_loader_request,
                        AppCacheStorage* storage);
 
   // AppCacheStorage::Delegate methods
   void OnResponseInfoLoaded(AppCacheResponseInfo* response_info,
                             int64_t response_id) override;
 
   // AppCacheResponseReader completion callback
   void OnReadComplete(int result);
 
   void OnConnectionError();
 
   // Helper to send the AppCacheResponseInfo to the URLLoaderClient.
   void SendResponseInfo();
 
   // Helper function to read the data from the AppCache.
   void ReadMore();
 
   // Callback invoked when the data pipe can be written to.
   void OnResponseBodyStreamReady(MojoResult result);
 
   // Notifies the client about request completion.
   void NotifyCompleted(int error_code);
 
+  // Creates the URLLoaderClient proxy. Used to setup the proxy URLLoaderClient
+  // which enables us to inspect responses coming back from the network service
+  // for AppCache fallback.
+  mojom::URLLoaderClientPtr CreateLoaderClientProxy();
+
   // The current request.
   ResourceRequest request_;
 
   base::WeakPtr<AppCacheStorage> storage_;
 
   // Time when the request started.
   base::TimeTicks start_time_tick_;
 
   // The AppCache manifest URL.
   GURL manifest_url_;
 
   // The AppCache id.
   int64_t cache_id_;
 
   AppCacheEntry entry_;
 
   // Set to true if we are loading fallback content.
   bool is_fallback_;
 
   // The data pipe used to transfer AppCache data to the client.
   mojo::DataPipe data_pipe_;
 
   // Binds the URLLoaderClient with us.
   mojo::Binding<mojom::URLLoader> binding_;
 
   // The URLLoaderClient pointer. We call this interface with notifications
   // about the URL load
   mojom::URLLoaderClientPtr client_info_;

[michaeln, 2017/07/18 19:19:22]

naming: client_
(_info sounds more like a data structure than an interface ptr)

[ananta, 2017/07/18 19:52:40]

Done.

 
   // mojo data pipe entities.
   mojo::ScopedDataPipeProducerHandle response_body_stream_;
 
   scoped_refptr<NetToMojoPendingBuffer> pending_write_;
 
   mojo::SimpleWatcher writable_handle_watcher_;
 
   // The Callback to be invoked in the network service land to indicate if
   // the main resource request can be serviced via the AppCache.
   LoaderCallback main_resource_loader_callback_;
 
   // We own the AppCacheRequestHandler instance for subresource requests.
   std::unique_ptr<AppCacheRequestHandler> sub_resource_handler_;
 
   scoped_refptr<URLLoaderFactoryGetter> default_url_loader_factory_getter_;
 
   // Holds subresource url loader information.
   std::unique_ptr<SubresourceLoadInfo> subresource_load_info_;
 
   // Timing information for the most recent request.  Its start times are
   // populated in DeliverAppCachedResponse().
   net::LoadTimingInfo load_timing_info_;
 
   // Used for subresource requests which go to the network.
   mojom::URLLoaderAssociatedPtr network_loader_request_;

[michaeln, 2017/07/18 19:19:22]

naming: network_loader_

[ananta, 2017/07/18 19:52:40]

Done.

 
   // Binds the subresource URLLoaderClient with us. We can use the regular
   // binding_ member above when we remove the need for the associated requests
   // issue with URLLoaderFactory.
   std::unique_ptr<mojo::AssociatedBinding<mojom::URLLoader>>
       associated_binding_;
 
+  // Proxy URLLoaderClient binding for subresource requests.
+  mojo::Binding<mojom::URLLoaderClient> loader_client_proxy_binding_;

[michaeln, 2017/07/18 19:19:22]

naming: network_loader_client_binding_

[ananta, 2017/07/18 19:52:40]

Done.

+
+  // The AppCacheURLLoaderRequest instance. We use this to set the response
+  // info when we receive it.
+  AppCacheURLLoaderRequest* url_loader_request_instance_;

[michaeln, 2017/07/18 19:19:22]

naming: appcache_request_

[ananta, 2017/07/18 19:52:40]

Done.

+
   DISALLOW_COPY_AND_ASSIGN(AppCacheURLLoaderJob);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_APPCACHE_APPCACHE_URL_LOADER_JOB_H_