Implementation of network level throttler.

net/http/http_network_transaction.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 NET_HTTP_HTTP_NETWORK_TRANSACTION_H_
 #define NET_HTTP_HTTP_NETWORK_TRANSACTION_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "crypto/ec_private_key.h"
 #include "net/base/net_error_details.h"
+#include "net/base/network_stream_throttler.h"
 #include "net/base/request_priority.h"
 #include "net/http/http_auth.h"
 #include "net/http/http_request_headers.h"
 #include "net/http/http_response_info.h"
 #include "net/http/http_stream_factory.h"
 #include "net/http/http_transaction.h"
 #include "net/log/net_log.h"
 #include "net/proxy/proxy_service.h"
 #include "net/socket/connection_attempts.h"
 #include "net/ssl/channel_id_service.h"
@@ skipping 14 matching lines @@
 class HttpStream;
 class HttpStreamRequest;
 class IOBuffer;
 class ProxyInfo;
 class SpdySession;
 class SSLPrivateKey;
 struct HttpRequestInfo;
 
 class NET_EXPORT_PRIVATE HttpNetworkTransaction
     : public HttpTransaction,
-      public HttpStreamRequest::Delegate {
+      public HttpStreamRequest::Delegate,
+      public NetworkStreamThrottler::Delegate {
  public:
   HttpNetworkTransaction(RequestPriority priority,
                          HttpNetworkSession* session);
 
   ~HttpNetworkTransaction() override;
 
   // HttpTransaction methods:
   int Start(const HttpRequestInfo* request_info,
             const CompletionCallback& callback,
             const BoundNetLog& net_log) override;
@@ skipping 53 matching lines @@
   void OnNeedsClientAuth(const SSLConfig& used_ssl_config,
                          SSLCertRequestInfo* cert_info) override;
   void OnHttpsProxyTunnelResponse(const HttpResponseInfo& response_info,
                                   const SSLConfig& used_ssl_config,
                                   const ProxyInfo& used_proxy_info,
                                   HttpStream* stream) override;
 
   void OnQuicBroken() override;
   void GetConnectionAttempts(ConnectionAttempts* out) const override;
 
+  // NetworkStreamThrottler::Delegate methods:
+  void OnThrottleStateChanged() override;
+
  private:
   friend class HttpNetworkTransactionSSLTest;
 
   FRIEND_TEST_ALL_PREFIXES(HttpNetworkTransactionTest,
                            ResetStateForRestart);
   FRIEND_TEST_ALL_PREFIXES(HttpNetworkTransactionTest, EnableNPN);
   FRIEND_TEST_ALL_PREFIXES(HttpNetworkTransactionTest, DisableNPN);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            WindowUpdateReceived);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            WindowUpdateSent);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            WindowUpdateOverflow);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            FlowControlStallResume);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            FlowControlStallResumeAfterSettings);
   FRIEND_TEST_ALL_PREFIXES(SpdyNetworkTransactionTest,
                            FlowControlNegativeSendWindowSize);
 
   enum State {
+    STATE_THROTTLE,
     STATE_NOTIFY_BEFORE_CREATE_STREAM,
     STATE_CREATE_STREAM,
     STATE_CREATE_STREAM_COMPLETE,
     STATE_INIT_STREAM,
     STATE_INIT_STREAM_COMPLETE,
     STATE_GENERATE_PROXY_AUTH_TOKEN,
     STATE_GENERATE_PROXY_AUTH_TOKEN_COMPLETE,
     STATE_GENERATE_SERVER_AUTH_TOKEN,
     STATE_GENERATE_SERVER_AUTH_TOKEN_COMPLETE,
     STATE_GET_PROVIDED_TOKEN_BINDING_KEY,
@@ skipping 26 matching lines @@
   void DoCallback(int result);
   void OnIOComplete(int result);
 
   // Runs the state transition loop.
   int DoLoop(int result);
 
   // Each of these methods corresponds to a State value.  Those with an input
   // argument receive the result from the previous state.  If a method returns
   // ERR_IO_PENDING, then the result from OnIOComplete will be passed to the
   // next state method as the result arg.
+  int DoThrottle();
   int DoNotifyBeforeCreateStream();
   int DoCreateStream();
   int DoCreateStreamComplete(int result);
   int DoInitStream();
   int DoInitStreamComplete(int result);
   int DoGenerateProxyAuthToken();
   int DoGenerateProxyAuthTokenComplete(int result);
   int DoGenerateServerAuthToken();
   int DoGenerateServerAuthTokenComplete(int result);
   int DoGetProvidedTokenBindingKey();
@@ skipping 183 matching lines @@
   WebSocketHandshakeStreamBase::CreateHelper*
       websocket_handshake_stream_base_create_helper_;
 
   BeforeNetworkStartCallback before_network_start_callback_;
   BeforeProxyHeadersSentCallback before_proxy_headers_sent_callback_;
 
   ConnectionAttempts connection_attempts_;
   IPEndPoint remote_endpoint_;
   // Network error details for this transaction.
   NetErrorDetails net_error_details_;
+
+  // Communciate lifetime of transaction to the throttler, and
+  // throttled state to the transaction.
+  std::unique_ptr<NetworkStreamThrottler::Throttle> throttle_;
+
   DISALLOW_COPY_AND_ASSIGN(HttpNetworkTransaction);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_NETWORK_TRANSACTION_H_