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.
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
10 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
12 #ifndef CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_
13 #define CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_
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"
27 class URLRequestStatus
;
31 class ResourceController
;
32 class ResourceMessageFilter
;
33 class ResourceRequestInfoImpl
;
34 struct ResourceResponse
;
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
) {
42 virtual ~ResourceHandler() {}
44 // Sets the controller for this handler.
45 virtual void SetController(ResourceController
* controller
);
47 // Called as upload progress is made. The return value is ignored.
48 virtual bool OnUploadProgress(int request_id
,
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
,
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
,
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;
76 // Called before the net::URLRequest for |request_id| (whose url is |url|}
77 // uses the network for the first time to load the resource. If the handler
78 // returns false, then the request is cancelled. Otherwise if the return value
79 // is true, the ResourceHandler can delay the request from starting by setting
80 // |*defer = true|. Call controller()->Resume() to continue if deferred.
81 virtual bool OnBeforeNetworkStart(int request_id
,
85 // Data will be read for the response. Upon success, this method places the
86 // size and address of the buffer where the data is to be written in its
87 // out-params. This call will be followed by either OnReadCompleted or
88 // OnResponseCompleted, at which point the buffer may be recycled.
90 // If the handler returns false, then the request is cancelled. Otherwise,
91 // once data is available, OnReadCompleted will be called.
92 virtual bool OnWillRead(int request_id
,
93 scoped_refptr
<net::IOBuffer
>* buf
,
97 // Data (*bytes_read bytes) was written into the buffer provided by
98 // OnWillRead. A return value of false cancels the request, true continues
99 // reading data. Set |*defer| to true to defer reading more response data.
100 // Call controller()->Resume() to continue reading response data.
101 virtual bool OnReadCompleted(int request_id
, int bytes_read
,
104 // The response is complete. The final response status is given. Set
105 // |*defer| to true to defer destruction to a later time. Otherwise, the
106 // request will be destroyed upon return.
107 virtual void OnResponseCompleted(int request_id
,
108 const net::URLRequestStatus
& status
,
109 const std::string
& security_info
,
112 // This notification is synthesized by the RedirectToFileResourceHandler
113 // to indicate progress of 'download_to_file' requests. OnReadCompleted
114 // calls are consumed by the RedirectToFileResourceHandler and replaced
115 // with OnDataDownloaded calls.
116 virtual void OnDataDownloaded(int request_id
, int bytes_downloaded
) = 0;
119 ResourceHandler(net::URLRequest
* request
);
121 ResourceController
* controller() const { return controller_
; }
122 net::URLRequest
* request() const { return request_
; }
124 // Convenience functions.
125 ResourceRequestInfoImpl
* GetRequestInfo() const;
126 int GetRequestID() const;
127 ResourceMessageFilter
* GetFilter() const;
130 ResourceController
* controller_
;
131 net::URLRequest
* request_
;
134 } // namespace content
136 #endif // CONTENT_BROWSER_LOADER_RESOURCE_HANDLER_H_