[Media Router] Add CastMediaSinkService

chrome/browser/media/router/discovery/mdns/cast_media_sink_service.h

+// Copyright 2017 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 CHROME_BROWSER_MEDIA_ROUTER_DISCOVERY_MDNS_CAST_MEDIA_SINK_SERVICE_H_
+#define CHROME_BROWSER_MEDIA_ROUTER_DISCOVERY_MDNS_CAST_MEDIA_SINK_SERVICE_H_
+
+#include <memory>
+#include <set>
+
+#include "base/memory/ref_counted.h"
+#include "base/threading/thread_checker.h"
+#include "chrome/browser/media/router/discovery/mdns/dns_sd_delegate.h"
+#include "chrome/browser/media/router/discovery/mdns/dns_sd_registry.h"
+#include "chrome/browser/media/router/discovery/media_sink_service_base.h"
+#include "components/cast_channel/cast_channel_enum.h"
+#include "extensions/browser/api/cast_channel/cast_socket_service.h"

[zhaobin, 2017/06/07 18:41:12]

This will become components/cast_channel/cast_socket_service after the
//extensions -> //components patch lands.

[zhaobin, 2017/06/10 02:19:35]

Done.

+
+namespace extensions {
+namespace api {
+namespace cast_channel {
+class CastSocketService;
+}  // namespace cast_channel
+}  // namespace api
+}  // namespace extensions
+
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+namespace media_router {
+
+// A service which can be used to start background discovery and resolution of
+// Cast devices (Smart TVs, Game Consoles, etc.).

[mark a. foltz, 2017/06/07 21:13:33]

Cast isn't supported on most smart TVs or game consoles.  So just leave off the
last part.

[zhaobin, 2017/06/10 02:19:35]

Done.

+// Public APIs should be invoked on the UI thread.
+class CastMediaSinkService
+    : public MediaSinkServiceBase,
+      public DnsSdRegistry::DnsSdObserver,
+      public base::RefCountedThreadSafe<CastMediaSinkService> {
+ public:
+  CastMediaSinkService(const OnSinksDiscoveredCallback& callback,
+                       content::BrowserContext* browser_context);
+
+  // MediaSinkService implementation
+  void Start() override;
+  void Stop() override;
+
+ protected:
+  // Used to mock out the DnsSdRegistry for testing.
+  void SetDnsSdRegistryForTesting(DnsSdRegistry* registry);
+
+ private:
+  friend class base::RefCountedThreadSafe<CastMediaSinkService>;
+
+  ~CastMediaSinkService() override;
+
+  // DnsSdRegistry::DnsSdObserver implementation
+  void OnDnsSdEvent(const std::string& service_type,
+                    const DnsSdRegistry::DnsSdServiceList& services) override;
+
+  // Open cast channel on IO thread.
+  // |service|: mDNS service description.
+  // |ip_endpoint|: cast channel's target IP endpoint.
+  void OpenChannelOnIOThread(const DnsSdService& service,
+                             const net::IPEndPoint& ip_endpoint);
+
+  // Invoked when opening cast channel on IO thread completes.
+  // |service|: mDNS service description.
+  // |channel_id|: channel id of newly created cast channel.
+  // |channel_error|: error encounted when opending cast channel.
+  void OnChannelOpenedOnIOThread(const DnsSdService& service,
+                                 int channel_id,
+                                 cast_channel::ChannelError channel_error);
+
+  // Invoked by |OnChannelOpenedOnIOThread| to post task on UI thread.
+  // |service|: mDNS service description.
+  // |channel_id|: channel id of newly created cast channel.
+  // |audio_only|: if cast channel is audio only or not.
+  void OnChannelOpenOnUIThread(const DnsSdService& service,
+                               int channel_id,
+                               bool audio_only);
+
+  // Raw pointer to DnsSdRegistry singleton.
+  DnsSdRegistry* dns_sd_registry_ = nullptr;
+
+  // Service list from current round of discovery.
+  DnsSdRegistry::DnsSdServiceList current_services_;
+
+  // Service managing creating and removing cast channels.
+  scoped_refptr<extensions::api::cast_channel::CastSocketService>
+      cast_socket_service_;
+
+  THREAD_CHECKER(thread_checker_);
+
+  DISALLOW_COPY_AND_ASSIGN(CastMediaSinkService);
+};
+
+}  // namespace media_router
+
+#endif  // CHROME_BROWSER_MEDIA_ROUTER_DISCOVERY_MDNS_CAST_MEDIA_SINK_SERVICE_H_