// Copyright 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_HANDLER_H_
#define GOOGLE_APIS_GCM_ENGINE_CONNECTION_HANDLER_H_
#include "base/callback.h"
#include "google_apis/gcm/base/gcm_export.h"
namespace net{
class StreamSocket;
} // namespace net
namespace google {
namespace protobuf {
class MessageLite;
} // namespace protobuf
} // namepsace google
namespace mcs_proto {
class LoginRequest;
}
namespace gcm {
class SocketInputStream;
class SocketOutputStream;
// Handles performing the protocol handshake and sending/receiving protobuf
// messages. Note that no retrying or queueing is enforced at this layer.
// Once a connection error is encountered, the ConnectionHandler will disconnect
// the socket and must be reinitialized with a new StreamSocket before
// messages can be sent/received again.
class GCM_EXPORT ConnectionHandler {
public:
typedef base::Callback<void(scoped_ptr<google::protobuf::MessageLite>)>
ProtoReceivedCallback;
typedef base::Closure ProtoSentCallback;
typedef base::Callback<void(int)> ConnectionChangedCallback;
ConnectionHandler();
virtual ~ConnectionHandler();
// Starts a new MCS connection handshake (using |login_request|) and, upon
// success, begins listening for incoming/outgoing messages.
//
// Note: It is correct and expected to call Init more than once, as connection
// issues are encountered and new connections must be made.
virtual void Init(const mcs_proto::LoginRequest& login_request,
net::StreamSocket* socket) = 0;
// Resets the handler and any internal state. Should be called any time
// a connection reset happens externally to the handler.
virtual void Reset() = 0;
// Checks that a handshake has been completed and a message is not already
// in flight.
virtual bool CanSendMessage() const = 0;
// Send an MCS protobuf message. CanSendMessage() must be true.
virtual void SendMessage(const google::protobuf::MessageLite& message) = 0;
};
} // namespace gcm
#endif // GOOGLE_APIS_GCM_ENGINE_CONNECTION_HANDLER_H_