1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // This is the browser side of the resource dispatcher, it receives requests 6 // from the RenderProcessHosts, and dispatches them to URLRequests. It then 7 // fowards the messages from the URLRequests back to the correct process for 8 // handling. 9 // 10 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading 11 12 #ifndef CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_ 13 #define CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_ 14 15 #include <string> 16 17 #include "base/memory/ref_counted.h" 18 #include "base/sequenced_task_runner_helpers.h" 19 #include "base/threading/non_thread_safe.h" 20 #include "content/common/content_export.h" 21 22 class GURL; 23 24 namespace net { 25 class IOBuffer; 26 class URLRequest; 27 class URLRequestStatus; 28 } // namespace net 29 30 namespace content { 31 class ResourceController; 32 class ResourceMessageFilter; 33 class ResourceRequestInfoImpl; 34 struct ResourceResponse; 35 36 // The resource dispatcher host uses this interface to process network events 37 // for an URLRequest instance. A ResourceHandler's lifetime is bound to its 38 // associated URLRequest. 39 class CONTENT_EXPORT ResourceHandler 40 : public NON_EXPORTED_BASE(base::NonThreadSafe) { 41 public: 42 virtual ~ResourceHandler() {} 43 44 // Sets the controller for this handler. 45 virtual void SetController(ResourceController* controller); 46 47 // Called as upload progress is made. The return value is ignored. 48 virtual bool OnUploadProgress(int request_id, 49 uint64 position, 50 uint64 size) = 0; 51 52 // The request was redirected to a new URL. |*defer| has an initial value of 53 // false. Set |*defer| to true to defer the redirect. The redirect may be 54 // followed later on via ResourceDispatcherHost::FollowDeferredRedirect. If 55 // the handler returns false, then the request is cancelled. 56 virtual bool OnRequestRedirected(int request_id, const GURL& url, 57 ResourceResponse* response, 58 bool* defer) = 0; 59 60 // Response headers and meta data are available. If the handler returns 61 // false, then the request is cancelled. Set |*defer| to true to defer 62 // processing of the response. Call ResourceDispatcherHostImpl:: 63 // ResumeDeferredRequest to continue processing the response. 64 virtual bool OnResponseStarted(int request_id, 65 ResourceResponse* response, 66 bool* defer) = 0; 67 68 // Called before the net::URLRequest for |request_id| (whose url is |url|) is 69 // to be started. If the handler returns false, then the request is 70 // cancelled. Otherwise if the return value is true, the ResourceHandler can 71 // delay the request from starting by setting |*defer = true|. A deferred 72 // request will not have called net::URLRequest::Start(), and will not resume 73 // until someone calls ResourceDispatcherHost::StartDeferredRequest(). 74 virtual bool OnWillStart(int request_id, const GURL& url, bool* defer) = 0; 75 76 // Data will be read for the response. Upon success, this method places the 77 // size and address of the buffer where the data is to be written in its 78 // out-params. This call will be followed by either OnReadCompleted or 79 // OnResponseCompleted, at which point the buffer may be recycled. 80 // 81 // If the handler returns false, then the request is cancelled. Otherwise, 82 // once data is available, OnReadCompleted will be called. 83 virtual bool OnWillRead(int request_id, 84 scoped_refptr<net::IOBuffer>* buf, 85 int* buf_size, 86 int min_size) = 0; 87 88 // Data (*bytes_read bytes) was written into the buffer provided by 89 // OnWillRead. A return value of false cancels the request, true continues 90 // reading data. Set |*defer| to true to defer reading more response data. 91 // Call controller()->Resume() to continue reading response data. 92 virtual bool OnReadCompleted(int request_id, int bytes_read, 93 bool* defer) = 0; 94 95 // The response is complete. The final response status is given. Set 96 // |*defer| to true to defer destruction to a later time. Otherwise, the 97 // request will be destroyed upon return. 98 virtual void OnResponseCompleted(int request_id, 99 const net::URLRequestStatus& status, 100 const std::string& security_info, 101 bool* defer) = 0; 102 103 // This notification is synthesized by the RedirectToFileResourceHandler 104 // to indicate progress of 'download_to_file' requests. OnReadCompleted 105 // calls are consumed by the RedirectToFileResourceHandler and replaced 106 // with OnDataDownloaded calls. 107 virtual void OnDataDownloaded(int request_id, int bytes_downloaded) = 0; 108 109 protected: 110 ResourceHandler(net::URLRequest* request); 111 112 ResourceController* controller() const { return controller_; } 113 net::URLRequest* request() const { return request_; } 114 115 // Convenience functions. 116 ResourceRequestInfoImpl* GetRequestInfo() const; 117 int GetRequestID() const; 118 ResourceMessageFilter* GetFilter() const; 119 120 private: 121 ResourceController* controller_; 122 net::URLRequest* request_; 123 }; 124 125 } // namespace content 126 127 #endif // CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_ 128
