1 // Copyright 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 #ifndef SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_
6 #define SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_
10 #include "base/basictypes.h"
11 #include "base/callback.h"
12 #include "base/compiler_specific.h"
13 #include "base/gtest_prod_util.h"
14 #include "base/memory/ref_counted.h"
15 #include "base/synchronization/lock.h"
16 #include "base/synchronization/waitable_event.h"
17 #include "net/base/network_time_notifier.h"
18 #include "net/url_request/url_fetcher_delegate.h"
19 #include "net/url_request/url_request_context.h"
20 #include "net/url_request/url_request_context_getter.h"
21 #include "sync/base/sync_export.h"
22 #include "sync/internal_api/public/base/cancelation_observer.h"
23 #include "sync/internal_api/public/http_post_provider_factory.h"
24 #include "sync/internal_api/public/http_post_provider_interface.h"
34 class HttpResponseHeaders;
35 class HttpUserAgentSettings;
41 class CancelationSignal;
43 // Callback for updating the network time.
45 // const base::Time& network_time - the new network time.
46 // const base::TimeDelta& resolution - how precise the reading is.
47 // const base::TimeDelta& latency - the http request's latency.
48 typedef base::Callback<void(const base::Time&,
49 const base::TimeDelta&,
50 const base::TimeDelta&)> NetworkTimeUpdateCallback;
52 // A bridge between the syncer and Chromium HTTP layers.
53 // Provides a way for the sync backend to use Chromium directly for HTTP
54 // requests rather than depending on a third party provider (e.g libcurl).
55 // This is a one-time use bridge. Create one for each request you want to make.
56 // It is RefCountedThreadSafe because it can PostTask to the io loop, and thus
57 // needs to stick around across context switches, etc.
58 class SYNC_EXPORT_PRIVATE HttpBridge
59 : public base::RefCountedThreadSafe<HttpBridge>,
60 public HttpPostProviderInterface,
61 public net::URLFetcherDelegate {
63 // A request context used for HTTP requests bridged from the sync backend.
64 // A bridged RequestContext has a dedicated in-memory cookie store and does
65 // not use a cache. Thus the same type can be used for incognito mode.
66 class RequestContext : public net::URLRequestContext {
68 // |baseline_context| is used to obtain the accept-language
69 // and proxy service information for bridged requests.
70 // Typically |baseline_context| should be the net::URLRequestContext of the
71 // currently active profile.
73 net::URLRequestContext* baseline_context,
74 const scoped_refptr<base::SingleThreadTaskRunner>&
76 const std::string& user_agent);
78 // The destructor MUST be called on the IO thread.
79 virtual ~RequestContext();
82 net::URLRequestContext* const baseline_context_;
83 const scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
84 scoped_ptr<net::HttpUserAgentSettings> http_user_agent_settings_;
86 DISALLOW_COPY_AND_ASSIGN(RequestContext);
89 // Lazy-getter for RequestContext objects.
90 class SYNC_EXPORT_PRIVATE RequestContextGetter
91 : public net::URLRequestContextGetter {
94 net::URLRequestContextGetter* baseline_context_getter,
95 const std::string& user_agent);
97 // net::URLRequestContextGetter implementation.
98 virtual net::URLRequestContext* GetURLRequestContext() OVERRIDE;
99 virtual scoped_refptr<base::SingleThreadTaskRunner>
100 GetNetworkTaskRunner() const OVERRIDE;
103 virtual ~RequestContextGetter();
106 scoped_refptr<net::URLRequestContextGetter> baseline_context_getter_;
107 const scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
108 // User agent to apply to the net::URLRequestContext.
109 const std::string user_agent_;
111 // Lazily initialized by GetURLRequestContext().
112 scoped_ptr<RequestContext> context_;
114 DISALLOW_COPY_AND_ASSIGN(RequestContextGetter);
117 HttpBridge(RequestContextGetter* context,
118 const NetworkTimeUpdateCallback& network_time_update_callback);
120 // HttpPostProvider implementation.
121 virtual void SetExtraRequestHeaders(const char* headers) OVERRIDE;
122 virtual void SetURL(const char* url, int port) OVERRIDE;
123 virtual void SetPostPayload(const char* content_type, int content_length,
124 const char* content) OVERRIDE;
125 virtual bool MakeSynchronousPost(int* error_code,
126 int* response_code) OVERRIDE;
127 virtual void Abort() OVERRIDE;
129 // WARNING: these response content methods are used to extract plain old data
130 // and not null terminated strings, so you should make sure you have read
131 // GetResponseContentLength() characters when using GetResponseContent. e.g
132 // string r(b->GetResponseContent(), b->GetResponseContentLength()).
133 virtual int GetResponseContentLength() const OVERRIDE;
134 virtual const char* GetResponseContent() const OVERRIDE;
135 virtual const std::string GetResponseHeaderValue(
136 const std::string& name) const OVERRIDE;
138 // net::URLFetcherDelegate implementation.
139 virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
141 net::URLRequestContextGetter* GetRequestContextGetterForTest() const;
144 friend class base::RefCountedThreadSafe<HttpBridge>;
146 virtual ~HttpBridge();
148 // Protected virtual so the unit test can override to shunt network requests.
149 virtual void MakeAsynchronousPost();
152 friend class SyncHttpBridgeTest;
153 friend class ::HttpBridgeTest;
155 // Called on the IO loop to issue the network request. The extra level
156 // of indirection is so that the unit test can override this behavior but we
157 // still have a function to statically pass to PostTask.
158 void CallMakeAsynchronousPost() { MakeAsynchronousPost(); }
160 // Used to destroy a fetcher when the bridge is Abort()ed, to ensure that
161 // a reference to |this| is held while flushing any pending fetch completion
162 // callbacks coming from the IO thread en route to finally destroying the
164 void DestroyURLFetcherOnIOThread(net::URLFetcher* fetcher);
166 void UpdateNetworkTime();
168 // The message loop of the thread we were created on. This is the thread that
169 // will block on MakeSynchronousPost while the IO thread fetches data from
171 // This should be the main syncer thread (SyncerThread) which is what blocks
172 // on network IO through curl_easy_perform.
173 base::MessageLoop* const created_on_loop_;
175 // The URL to POST to.
176 GURL url_for_request_;
178 // POST payload information.
179 std::string content_type_;
180 std::string request_content_;
181 std::string extra_headers_;
183 // A waitable event we use to provide blocking semantics to
184 // MakeSynchronousPost. We block created_on_loop_ while the IO loop fetches
186 base::WaitableEvent http_post_completed_;
188 struct URLFetchState {
191 // Our hook into the network layer is a URLFetcher. USED ONLY ON THE IO
192 // LOOP, so we can block created_on_loop_ while the fetch is in progress.
193 // NOTE: This is not a scoped_ptr for a reason. It must be deleted on the
194 // same thread that created it, which isn't the same thread |this| gets
195 // deleted on. We must manually delete url_poster_ on the IO loop.
196 net::URLFetcher* url_poster;
198 // Start and finish time of request. Set immediately before sending
199 // request and after receiving response.
200 base::Time start_time;
203 // Used to support 'Abort' functionality.
206 // Cached response data.
207 bool request_completed;
208 bool request_succeeded;
209 int http_response_code;
211 std::string response_content;
212 scoped_refptr<net::HttpResponseHeaders> response_headers;
215 // This lock synchronizes use of state involved in the flow to fetch a URL
216 // using URLFetcher, including |fetch_state_| and
217 // |context_getter_for_request_| on any thread, for example, this flow needs
218 // to be synchronized to gracefully clean up URLFetcher and return
219 // appropriate values in |error_code|.
220 mutable base::Lock fetch_state_lock_;
221 URLFetchState fetch_state_;
223 // Gets a customized net::URLRequestContext for bridged requests. See
224 // RequestContext definition for details.
225 scoped_refptr<RequestContextGetter> context_getter_for_request_;
227 const scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
229 // Callback for updating network time.
230 NetworkTimeUpdateCallback network_time_update_callback_;
232 DISALLOW_COPY_AND_ASSIGN(HttpBridge);
235 class SYNC_EXPORT HttpBridgeFactory : public HttpPostProviderFactory,
236 public CancelationObserver {
239 net::URLRequestContextGetter* baseline_context_getter,
240 const NetworkTimeUpdateCallback& network_time_update_callback,
241 CancelationSignal* cancelation_signal);
242 virtual ~HttpBridgeFactory();
244 // HttpPostProviderFactory:
245 virtual void Init(const std::string& user_agent) OVERRIDE;
246 virtual HttpPostProviderInterface* Create() OVERRIDE;
247 virtual void Destroy(HttpPostProviderInterface* http) OVERRIDE;
249 // CancelationObserver implementation:
250 virtual void OnSignalReceived() OVERRIDE;
253 // Protects |request_context_getter_| and |baseline_request_context_getter_|.
254 base::Lock context_getter_lock_;
256 // This request context is the starting point for the request_context_getter_
257 // that we eventually use to make requests. During shutdown we must drop all
258 // references to it before the ProfileSyncService's Shutdown() call is
260 scoped_refptr<net::URLRequestContextGetter> baseline_request_context_getter_;
262 // This request context is built on top of the baseline context and shares
263 // common components. Takes a reference to the
264 // baseline_request_context_getter_. It's mostly used on sync thread when
265 // creating connection but is released as soon as possible during shutdown.
266 // Protected by |context_getter_lock_|.
267 scoped_refptr<HttpBridge::RequestContextGetter> request_context_getter_;
269 NetworkTimeUpdateCallback network_time_update_callback_;
271 CancelationSignal* const cancelation_signal_;
273 DISALLOW_COPY_AND_ASSIGN(HttpBridgeFactory);
276 } // namespace syncer
278 #endif // SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_