[GCM] Add port 443 fallback logic and histograms

google_apis/gcm/engine/connection_factory_impl.h

 // Copyright (c) 2013 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 GOOGLE_APIS_GCM_ENGINE_CONNECTION_FACTORY_IMPL_H_
 #define GOOGLE_APIS_GCM_ENGINE_CONNECTION_FACTORY_IMPL_H_
 
 #include "google_apis/gcm/engine/connection_factory.h"
 
 #include "base/memory/weak_ptr.h"
@@ skipping 14 matching lines @@
 namespace gcm {
 
 class ConnectionHandlerImpl;
 
 class GCM_EXPORT ConnectionFactoryImpl :
     public ConnectionFactory,
     public net::NetworkChangeNotifier::ConnectionTypeObserver,
     public net::NetworkChangeNotifier::IPAddressObserver {
  public:
   ConnectionFactoryImpl(
-      const GURL& mcs_endpoint,
+      const std::vector<GURL>& mcs_endpoints,
       const net::BackoffEntry::Policy& backoff_policy,
       scoped_refptr<net::HttpNetworkSession> network_session,
       net::NetLog* net_log);
   virtual ~ConnectionFactoryImpl();
 
   // ConnectionFactory implementation.
   virtual void Initialize(
       const BuildLoginRequestCallback& request_builder,
       const ConnectionHandler::ProtoReceivedCallback& read_callback,
       const ConnectionHandler::ProtoSentCallback& write_callback) OVERRIDE;
   virtual ConnectionHandler* GetConnectionHandler() const OVERRIDE;
   virtual void Connect() OVERRIDE;
   virtual bool IsEndpointReachable() const OVERRIDE;
   virtual base::TimeTicks NextRetryAttempt() const OVERRIDE;
   virtual void SignalConnectionReset(ConnectionResetReason reason) OVERRIDE;
 
   // NetworkChangeNotifier observer implementations.
   virtual void OnConnectionTypeChanged(
       net::NetworkChangeNotifier::ConnectionType type) OVERRIDE;
   virtual void OnIPAddressChanged() OVERRIDE;
 
+  // Returns the server to which the factory is currently connected, or if
+  // a connection is currently pending, the server to which the next connection
+  // attempt will be made.
+  GURL GetCurrentEndpoint() const;
+
  protected:
   // Implementation of Connect(..). If not in backoff, uses |login_request_|
   // in attempting a connection/handshake. On connection/handshake failure, goes
   // into backoff.
   // Virtual for testing.
   virtual void ConnectImpl();
 
   // Helper method for initalizing the connection hander.
   // Virtual for testing.
   virtual void InitHandler();
@@ skipping 15 matching lines @@
 
  private:
   // Proxy resolution and connection functions.
   void OnProxyResolveDone(int status);
   void OnProxyConnectDone(int status);
   int ReconsiderProxyAfterError(int error);
   void ReportSuccessfulProxyConnection();
 
   void CloseSocket();
 
-  // The MCS endpoint to make connections to.
-  const GURL mcs_endpoint_;
+  // The MCS endpoints to make connections to, sorted in order of priority.
+  const std::vector<GURL> mcs_endpoints_;
+  // Index to the endpoint for which a connection should be attempted next.
+  size_t next_endpoint_;
+  // Index to the endpoint that was last successfully connected.
+  size_t last_successful_endpoint_;
 
   // The backoff policy to use.
   const net::BackoffEntry::Policy backoff_policy_;
 
   // ---- net:: components for establishing connections. ----
   // Network session for creating new connections.
   const scoped_refptr<net::HttpNetworkSession> network_session_;
   // Net log to use in connection attempts.
   net::BoundNetLog bound_net_log_;
   // The current PAC request, if one exists. Owned by the proxy service.
@@ skipping 29 matching lines @@
   BuildLoginRequestCallback request_builder_;
 
   base::WeakPtrFactory<ConnectionFactoryImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ConnectionFactoryImpl);
 };
 
 }  // namespace gcm
 
 #endif  // GOOGLE_APIS_GCM_ENGINE_CONNECTION_FACTORY_IMPL_H_