Implementation and fixes for Blimp client/engine E2E communication.

blimp/net/browser_connection_handler.cc

 // 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.
 
 #include "blimp/net/browser_connection_handler.h"
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "blimp/net/blimp_connection.h"
 #include "blimp/net/blimp_message_demultiplexer.h"
@@ skipping 20 matching lines @@
 
 scoped_ptr<BlimpMessageProcessor> BrowserConnectionHandler::RegisterFeature(
     BlimpMessage::Type type,
     BlimpMessageProcessor* incoming_processor) {
   demultiplexer_->AddProcessor(type, incoming_processor);
   return multiplexer_->CreateSenderForType(type);
 }
 
 void BrowserConnectionHandler::HandleConnection(
     scoped_ptr<BlimpConnection> connection) {
-  // Since there is only a single Client, assume a newer connection should
-  // replace an existing one.
-  DropCurrentConnection();
+  VLOG(1) << "HandleConnection " << connection;
+
+  if (connection_) {
+    // We will be clobbering |connection_| intentionally, so squelch any
+    // socket errors that might arise.
+    connection_->SetConnectionErrorObserver(nullptr);

[haibinlu, 2015/12/29 00:51:45]

why remove "connection_->SetIncomingMessageProcessor(nullptr)" and
"output_buffer_->SetOutputProcessor(nullptr);"

[Kevin M, 2015/12/30 23:08:49]

Both are redundant. Deleting |connection_| renders the value of its incoming
message processor moot - it's dead anyways. Resetting the CancelableCallback in
the OutputBuffer implicitly cancels existing callbacks, so there's no need to
cancel it again beforehand.

+  }
   connection_ = std::move(connection);
-  connection_->SetConnectionErrorObserver(this);
 
   // Connect the incoming & outgoing message streams.
+  connection_->SetConnectionErrorObserver(this);

[haibinlu, 2015/12/29 00:51:45]

move this up or update the comment above.

[Kevin M, 2015/12/30 23:08:49]

Done.

   connection_->SetIncomingMessageProcessor(demultiplexer_.get());
   output_buffer_->SetOutputProcessor(
       connection_->GetOutgoingMessageProcessor());
 }
 
-void BrowserConnectionHandler::DropCurrentConnection() {
-  if (!connection_)
-    return;
-
-  connection_->SetConnectionErrorObserver(nullptr);
-  connection_->SetIncomingMessageProcessor(nullptr);
+void BrowserConnectionHandler::OnConnectionError(int error) {
+  VLOG(1) << "OnConnectionError: " << net::ErrorToString(error);
+  connection_.reset();
   output_buffer_->SetOutputProcessor(nullptr);
-  connection_.reset();
-}
-
-void BrowserConnectionHandler::OnConnectionError(int error) {
-  LOG(WARNING) << "Connection error " << net::ErrorToString(error);
-  DropCurrentConnection();
 }
 
 }  // namespace blimp