Add status service for remoting host.

remoting/host/host_status_service.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 REMOTING_HOST_HOST_STATUS_SERVICE_H_
+#define REMOTING_HOST_HOST_STATUS_SERVICE_H_
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "remoting/host/websocket_listener.h"
+
+namespace base {
+class DictionaryValue;
+}  // namespace remoting
+
+namespace remoting {
+
+class HostStatusService {

[alexeypa (please no reviews), 2012/11/15 19:45:56]

nit: Add a comment explaining what is this class for.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

+ public:
+  HostStatusService();
+  ~HostStatusService();
+
+  void SetState(bool started, const std::string& host_id);

[alexeypa (please no reviews), 2012/11/15 19:45:56]

nit: Add a comment explaining what this method does.

[Wez, 2012/11/15 23:34:59]

nit: I think it's cleaner to have two separate setters for these.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

+
+ private:
+  class Connection;

[Wez, 2012/11/15 23:34:59]

We seem to be re-inventing the socket-server wheel here, again; is there no
existing class we can re-use for this?

[Sergey Ulanov, 2012/11/16 00:52:10]

I'm not sure what you mean. We need to allow multiple parallel connections to
the service (e.g. from different instances of the webapp), this requires having
a class that knows how to handle messages from each connection separately. 

+  friend class Connection;
+
+  bool IsAllowedOrigin(const std::string& origin);

[alexeypa (please no reviews), 2012/11/15 19:45:56]

nit: Add a comment explaining what this method does.

[Sergey Ulanov, 2012/11/16 00:52:10]

Added, but I think the name of the method is descriptive enough.

[Wez, 2012/11/20 05:55:53]

What I meant was a comment like "Returns true if |origin| is one of the remoting
extension URLs." for example.

[Sergey Ulanov, 2012/11/22 00:29:35]

Done.

+
+  // Callback for WebsocketListener.
+  void OnNewConnection(scoped_ptr<WebsocketConnection> connection);
+
+  // Called from Connection instances.
+  void OnConnectionClosed(Connection* connection);
+  scoped_ptr<base::DictionaryValue> GetStatusMessage();

[alexeypa (please no reviews), 2012/11/15 19:45:56]

nit: Add a comment explaining what this method does.

[Wez, 2012/11/15 23:34:59]

And similarly the comments for OnFoo should describe what OnFoo does.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

+
+  WebsocketListener websocket_listener_;

[alexeypa (please no reviews), 2012/11/15 19:45:56]

nit: Add comments explaining what these member variables are for.

[Sergey Ulanov, 2012/11/16 00:52:10]

The purpose of |websocket_listener_| and |connections_| should be obvious from
the names. Added comments for other memebers.

+  std::string host_name_;

[Wez, 2012/11/15 23:34:59]

nit: Add a comment explaining what this is used for, and re-name to something
more descriptive; specifically, this is not the name of the host whose status we
are reporting, but actually some socket name.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done. Renamed to service_host_name_

+  std::set<Connection*> connections_;
+
+  bool started_;
+  std::string host_id_;

[Wez, 2012/11/15 23:34:59]

nit: Add a comment e.g. "State values to provide to clients.

[Sergey Ulanov, 2012/11/16 00:52:10]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(HostStatusService);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_HOST_HOST_STATUS_SERVICE_H_