Reporting of policy errors via host-offline-reason: part 3

remoting/host/host_signaling_manager.h

+// Copyright 2014 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_SIGNALING_MANAGER_H_
+#define REMOTING_HOST_HOST_SIGNALING_MANAGER_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "remoting/base/auto_thread_task_runner.h"
+#include "remoting/base/rsa_key_pair.h"
+#include "remoting/host/oauth_token_getter.h"
+#include "remoting/signaling/xmpp_signal_strategy.h"
+
+namespace base {
+class TimeDelta;
+}
+
+namespace net {
+class NetworkChangeNotifier;
+}
+
+namespace remoting {
+
+class ChromotingHostContext;
+class DnsBlackholeChecker;
+class HeartbeatSender;
+class OAuthTokenGetter;
+class SignalStrategy;
+class SignalingConnector;
+
+// HostSignalingManager has 2 functions:
+// 1. Keep sending regular heartbeats to the Chromoting Directory.
+// 2. Keep the host process alive while sending host-offline-reason heartbeat.
+class HostSignalingManager {
+ public:
+  class Listener {
+   public:
+    virtual ~Listener() {}
+
+    // Invoked after the first successful heartbeat.
+    virtual void OnHeartbeatSuccessful() = 0;
+
+    // Invoked when the host ID is permanently not recognized by the server.
+    virtual void OnUnknownHostIdError() = 0;
+
+    // Invoked when authentication fails.
+    virtual void OnAuthFailed() = 0;
+  };
+
+  // TODO(lukasza): Refactor to limit the number of parameters below.
+  // Probably necessitates refactoring HostProcess to extract a new
+  // class to read and store config/policy/cmdline values.
+  //
+  // |listener| has to be valid until either
+  //    1) the returned HostSignalingManager is destroyed
+  // or 2) SendHostOfflineReasonAndDelete is called.
+  static scoped_ptr<HostSignalingManager> Create(
+      Listener* listener,
+      const scoped_refptr<AutoThreadTaskRunner>& network_task_runner,
+      const scoped_refptr<net::URLRequestContextGetter>&
+          url_request_context_getter,
+      const XmppSignalStrategy::XmppServerConfig& xmpp_server_config,
+      const std::string& talkgadget_prefix_policy,
+      const std::string& host_id,
+      const scoped_refptr<const RsaKeyPair>& host_key_pair,
+      const std::string& directory_bot_jid,
+      scoped_ptr<OAuthTokenGetter::OAuthCredentials> oauth_credentials);
+
+  ~HostSignalingManager();
+
+  // Get the SignalStrategy to use for talking to the Chromoting bot.
+  // Returned SignalStrategy remains owned by the HostSignalingManager.
+  SignalStrategy* signal_strategy() { return signal_strategy_.get(); }
+
+  // Kicks off sending a heartbeat containing a host-offline-reason attribute.
+  // Prevents future calls to the |listener| provided to the Create method.
+  //
+  // Will delete |this| once either the bot acks receiving the
+  // |host_offline_reason|, or the |timeout| is reached.  Deleting
+  // |this| will release |network_task_runner_| and allow the host
+  // process to exit.
+  void SendHostOfflineReasonAndDelete(const std::string& host_offline_reason,
+                                      const base::TimeDelta& timeout);
+
+ private:
+  HostSignalingManager(
+      scoped_ptr<base::WeakPtrFactory<Listener>> weak_factory_for_listener,
+      const scoped_refptr<AutoThreadTaskRunner>& network_task_runner,
+      scoped_ptr<net::NetworkChangeNotifier> network_change_notifier,
+      scoped_ptr<SignalStrategy> signal_strategy,
+      scoped_ptr<SignalingConnector> signaling_connector,
+      scoped_ptr<HeartbeatSender> heartbeat_sender);
+
+  void OnHostOfflineReasonAck(bool success);
+
+  // Used to bind HeartbeatSender and SignalingConnector callbacks to |listener|
+  // in a way that allows "detaching" the |listener| when either |this| is
+  // destoyed or when SendHostOfflineReasonAndDelete method is called.

[Wez, 2015/01/10 01:43:32]

typo: destroyed

+  scoped_ptr<base::WeakPtrFactory<Listener>> weak_factory_for_listener_;
+
+  // By holding a reference to |network_task_runner_|, HostSignalingManager is
+  // extending the lifetime of the host process.  This is needed for the case
+  // where an instance of HostProcess has been already destroyed, but we want

[Wez, 2015/01/10 01:43:32]

nit: already been

[Łukasz Anforowicz, 2015/01/12 18:05:14]

Done.  I actually had this written the other way around and thought that this
sounds more English-like this way... oh, well... :-)

+  // to keep the process running while SendHostOfflineReasonAndDelete tries to

[Wez, 2015/01/10 01:43:32]

nit: No need for the full method name; suggest "... while we try to ..."

[Łukasz Anforowicz, 2015/01/12 18:05:14]

Done.

+  // establish a connection and send host-offline-reason.
+  scoped_refptr<AutoThreadTaskRunner> network_task_runner_;
+
+  // Order of fields below is important for destroying them in the right order.
+  // - |heartbeat_sender_| and |signaling_connector_| have to be destroyed
+  //   before |signal_strategy_| because their destructors need to call
+  //   signal_strategy_->RemoveListener(this)
+  // - |signaling_connector_| has to be destroyed before
+  //   |network_change_notifier_| because its destructor needs to deregister
+  //   network change notifications
+  scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
+  scoped_ptr<SignalStrategy> signal_strategy_;
+  scoped_ptr<SignalingConnector> signaling_connector_;
+  scoped_ptr<HeartbeatSender> heartbeat_sender_;
+
+  DISALLOW_COPY_AND_ASSIGN(HostSignalingManager);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_HOST_HOST_SIGNALING_MANAGER_H_