[Sync] Move HttpBridge to sync/

chrome/browser/sync/glue/http_bridge.h

-// Copyright (c) 2012 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 CHROME_BROWSER_SYNC_GLUE_HTTP_BRIDGE_H_
-#define CHROME_BROWSER_SYNC_GLUE_HTTP_BRIDGE_H_
-#pragma once
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/gtest_prod_util.h"
-#include "base/memory/ref_counted.h"
-#include "base/synchronization/lock.h"
-#include "base/synchronization/waitable_event.h"
-#include "googleurl/src/gurl.h"
-#include "net/url_request/url_fetcher_delegate.h"
-#include "net/url_request/url_request_context.h"
-#include "net/url_request/url_request_context_getter.h"
-#include "sync/internal_api/public/http_post_provider_factory.h"
-#include "sync/internal_api/public/http_post_provider_interface.h"
-
-class MessageLoop;
-class HttpBridgeTest;
-
-namespace net {
-class HttpResponseHeaders;
-class URLFetcher;
-}
-
-namespace browser_sync {
-
-// A bridge between the syncer and Chromium HTTP layers.
-// Provides a way for the sync backend to use Chromium directly for HTTP
-// requests rather than depending on a third party provider (e.g libcurl).
-// This is a one-time use bridge. Create one for each request you want to make.
-// It is RefCountedThreadSafe because it can PostTask to the io loop, and thus
-// needs to stick around across context switches, etc.
-class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
-                   public csync::HttpPostProviderInterface,
-                   public net::URLFetcherDelegate {
- public:
-  // A request context used for HTTP requests bridged from the sync backend.
-  // A bridged RequestContext has a dedicated in-memory cookie store and does
-  // not use a cache. Thus the same type can be used for incognito mode.
-  class RequestContext : public net::URLRequestContext {
-   public:
-    // |baseline_context| is used to obtain the accept-language,
-    // accept-charsets, and proxy service information for bridged requests.
-    // Typically |baseline_context| should be the net::URLRequestContext of the
-    // currently active profile.
-    explicit RequestContext(net::URLRequestContext* baseline_context);
-
-    // The destructor MUST be called on the IO thread.
-    virtual ~RequestContext();
-
-    // Set the user agent for requests using this context. The default is
-    // the browser's UA string.
-    void set_user_agent(const std::string& ua) { user_agent_ = ua; }
-
-    virtual const std::string& GetUserAgent(const GURL& url) const OVERRIDE {
-      // If the user agent is set explicitly return that, otherwise call the
-      // base class method to return default value.
-      return user_agent_.empty() ?
-          net::URLRequestContext::GetUserAgent(url) : user_agent_;
-    }
-
-   private:
-    std::string user_agent_;
-    net::URLRequestContext* baseline_context_;
-
-    DISALLOW_COPY_AND_ASSIGN(RequestContext);
-  };
-
-  // Lazy-getter for RequestContext objects.
-  class RequestContextGetter : public net::URLRequestContextGetter {
-   public:
-    explicit RequestContextGetter(
-        net::URLRequestContextGetter* baseline_context_getter);
-
-    void set_user_agent(const std::string& ua) { user_agent_ = ua; }
-    bool is_user_agent_set() const { return !user_agent_.empty(); }
-
-    // net::URLRequestContextGetter implementation.
-    virtual net::URLRequestContext* GetURLRequestContext() OVERRIDE;
-    virtual scoped_refptr<base::SingleThreadTaskRunner>
-        GetNetworkTaskRunner() const OVERRIDE;
-
-   protected:
-    virtual ~RequestContextGetter();
-
-   private:
-    // User agent to apply to the net::URLRequestContext.
-    std::string user_agent_;
-
-    scoped_refptr<net::URLRequestContextGetter> baseline_context_getter_;
-
-    // Lazily initialized by GetURLRequestContext().
-    scoped_ptr<RequestContext> context_;
-
-    DISALLOW_COPY_AND_ASSIGN(RequestContextGetter);
-  };
-
-  explicit HttpBridge(RequestContextGetter* context);
-
-  // csync::HttpPostProvider implementation.
-  virtual void SetUserAgent(const char* user_agent) OVERRIDE;
-  virtual void SetExtraRequestHeaders(const char* headers) OVERRIDE;
-  virtual void SetURL(const char* url, int port) OVERRIDE;
-  virtual void SetPostPayload(const char* content_type, int content_length,
-                              const char* content) OVERRIDE;
-  virtual bool MakeSynchronousPost(int* error_code,
-                                   int* response_code) OVERRIDE;
-  virtual void Abort() OVERRIDE;
-
-  // WARNING: these response content methods are used to extract plain old data
-  // and not null terminated strings, so you should make sure you have read
-  // GetResponseContentLength() characters when using GetResponseContent. e.g
-  // string r(b->GetResponseContent(), b->GetResponseContentLength()).
-  virtual int GetResponseContentLength() const OVERRIDE;
-  virtual const char* GetResponseContent() const OVERRIDE;
-  virtual const std::string GetResponseHeaderValue(
-      const std::string& name) const OVERRIDE;
-
-  // net::URLFetcherDelegate implementation.
-  virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
-
-#if defined(UNIT_TEST)
-  net::URLRequestContextGetter* GetRequestContextGetter() const {
-    return context_getter_for_request_;
-  }
-#endif
-
- protected:
-  friend class base::RefCountedThreadSafe<HttpBridge>;
-
-  virtual ~HttpBridge();
-
-  // Protected virtual so the unit test can override to shunt network requests.
-  virtual void MakeAsynchronousPost();
-
- private:
-  friend class ::HttpBridgeTest;
-
-  // Called on the IO loop to issue the network request. The extra level
-  // of indirection is so that the unit test can override this behavior but we
-  // still have a function to statically pass to PostTask.
-  void CallMakeAsynchronousPost() { MakeAsynchronousPost(); }
-
-  // Used to destroy a fetcher when the bridge is Abort()ed, to ensure that
-  // a reference to |this| is held while flushing any pending fetch completion
-  // callbacks coming from the IO thread en route to finally destroying the
-  // fetcher.
-  void DestroyURLFetcherOnIOThread(net::URLFetcher* fetcher);
-
-  // Gets a customized net::URLRequestContext for bridged requests. See
-  // RequestContext definition for details.
-  scoped_refptr<RequestContextGetter> context_getter_for_request_;
-
-  // The message loop of the thread we were created on. This is the thread that
-  // will block on MakeSynchronousPost while the IO thread fetches data from
-  // the network.
-  // This should be the main syncer thread (SyncerThread) which is what blocks
-  // on network IO through curl_easy_perform.
-  MessageLoop* const created_on_loop_;
-
-  // The URL to POST to.
-  GURL url_for_request_;
-
-  // POST payload information.
-  std::string content_type_;
-  std::string request_content_;
-  std::string extra_headers_;
-
-  // A waitable event we use to provide blocking semantics to
-  // MakeSynchronousPost. We block created_on_loop_ while the IO loop fetches
-  // network request.
-  base::WaitableEvent http_post_completed_;
-
-  struct URLFetchState {
-    URLFetchState();
-    ~URLFetchState();
-    // Our hook into the network layer is a URLFetcher. USED ONLY ON THE IO
-    // LOOP, so we can block created_on_loop_ while the fetch is in progress.
-    // NOTE: This is not a scoped_ptr for a reason. It must be deleted on the
-    // same thread that created it, which isn't the same thread |this| gets
-    // deleted on. We must manually delete url_poster_ on the IO loop.
-    net::URLFetcher* url_poster;
-
-    // Used to support 'Abort' functionality.
-    bool aborted;
-
-    // Cached response data.
-    bool request_completed;
-    bool request_succeeded;
-    int http_response_code;
-    int error_code;
-    std::string response_content;
-    scoped_refptr<net::HttpResponseHeaders> response_headers;
-  };
-
-  // This lock synchronizes use of state involved in the flow to fetch a URL
-  // using URLFetcher.  Because we can Abort() from any thread, for example,
-  // this flow needs to be synchronized to gracefully clean up URLFetcher and
-  // return appropriate values in |error_code|.
-  mutable base::Lock fetch_state_lock_;
-  URLFetchState fetch_state_;
-
-  DISALLOW_COPY_AND_ASSIGN(HttpBridge);
-};
-
-class HttpBridgeFactory : public csync::HttpPostProviderFactory {
- public:
-  explicit HttpBridgeFactory(
-      net::URLRequestContextGetter* baseline_context_getter);
-  virtual ~HttpBridgeFactory();
-
-  // csync::HttpPostProviderFactory:
-  virtual csync::HttpPostProviderInterface* Create() OVERRIDE;
-  virtual void Destroy(csync::HttpPostProviderInterface* http) OVERRIDE;
-
- private:
-  // This request context is built on top of the baseline context and shares
-  // common components.
-  HttpBridge::RequestContextGetter* GetRequestContextGetter();
-
-  scoped_refptr<HttpBridge::RequestContextGetter> request_context_getter_;
-
-  DISALLOW_COPY_AND_ASSIGN(HttpBridgeFactory);
-};
-
-}  //  namespace browser_sync
-
-#endif  // CHROME_BROWSER_SYNC_GLUE_HTTP_BRIDGE_H_