[Blimp Net] Adds BrowserConnectionHandler.

It Contains a demultiplexer for routing incoming messages to their respective
features, and a multiplexer/buffer object for writing outgoing messages.

It is created on browser startup, and persists for the lifetime of the application.

BUG=561207

Review URL: https://codereview.chromium.org/1474583002

Cr-Commit-Position: refs/heads/master@{#362192}

1 files changed, 70 insertions, 0 deletions

diff --git a/blimp/net/browser_connection_handler.h b/blimp/net/browser_connection_handler.h
new file mode 100644
index 0000000..d739e50
--- /dev/null
+++ b/blimp/net/browser_connection_handler.h
@@ -0,0 +1,70 @@
+// Copyright 2015 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 BLIMP_NET_BROWSER_CONNECTION_HANDLER_H_
+#define BLIMP_NET_BROWSER_CONNECTION_HANDLER_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "blimp/common/proto/blimp_message.pb.h"
+#include "blimp/net/blimp_net_export.h"
+#include "blimp/net/connection_error_observer.h"
+#include "blimp/net/connection_handler.h"
+
+namespace blimp {
+
+class BlimpConnection;
+class BlimpMessageDemultiplexer;
+class BlimpMessageMultiplexer;
+class BlimpMessageOutputBuffer;
+class BlimpMessageProcessor;
+
+// Routes incoming messages to their respective features, and buffers and sends
+// messages out via underlying BlimpConnection.
+// A BrowserConnectionHandler is created on browser startup, and persists for
+// the lifetime of the application.
+class BLIMP_NET_EXPORT BrowserConnectionHandler
+    : public ConnectionHandler,
+      public ConnectionErrorObserver {
+  BrowserConnectionHandler();
+  ~BrowserConnectionHandler() override;
+
+  // Registers a message processor which will receive all messages of the |type|
+  // specified. Only one handler may be added per type.
+  // That caller must ensure |incoming_processor| remains valid while
+  // this object is in-use.
+  //
+  // Returns a BlimpMessageProcessor object for sending messages of type |type|.
+  scoped_ptr<BlimpMessageProcessor> RegisterFeature(
+      BlimpMessage::Type type,
+      BlimpMessageProcessor* incoming_processor);
+
+  // ConnectionHandler implementation.
+  void HandleConnection(scoped_ptr<BlimpConnection> connection) override;
+
+  // ConnectionErrorObserver implementation.
+  void OnConnectionError(int error) override;
+
+ private:
+  void DropCurrentConnection();
+
+  // Holds network resources while there is a Client connected.
+  scoped_ptr<BlimpConnection> connection_;
+
+  // Routes incoming messages to the relevant feature-specific handlers.
+  scoped_ptr<BlimpMessageDemultiplexer> demultiplexer_;
+
+  // Provides buffering of outgoing messages, for use in session-recovery.
+  scoped_ptr<BlimpMessageOutputBuffer> output_buffer_;
+
+  // Routes outgoing messages from feature-specific handlers to a single
+  // message stream.
+  scoped_ptr<BlimpMessageMultiplexer> multiplexer_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserConnectionHandler);
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_NET_BROWSER_CONNECTION_HANDLER_H_