[Presentation API] (browser side) Implement reconnect() for 1-UA mode

chrome/browser/media/router/offscreen_presentation_manager.h

 // Copyright 2016 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_OFFSCREEN_PRESENTATION_MANAGER_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_OFFSCREEN_PRESENTATION_MANAGER_H_
 
 #include <map>
 #include <memory>
 #include <string>
 #include <unordered_map>
 
 #include "base/macros.h"
 #include "base/threading/thread_checker.h"
+#include "chrome/browser/media/router/media_route.h"
 #include "chrome/browser/media/router/render_frame_host_id.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "content/public/browser/presentation_service_delegate.h"
 
 class GURL;
 
 namespace media_router {
 // Manages all offscreen presentations started in the associated Profile and
 // facilitates communication between the controllers and the receiver of an
 // offscreen presentation.
@@ skipping 101 matching lines @@
   virtual void OnOffscreenPresentationReceiverCreated(
       const std::string& presentation_id,
       const GURL& presentation_url,
       const content::ReceiverConnectionAvailableCallback& receiver_callback);
 
   // Unregisters ReceiverConnectionAvailableCallback associated with
   // |presentation_id|.
   virtual void OnOffscreenPresentationReceiverTerminated(
       const std::string& presentation_id);
 
+  // Register |route| to offscreen presentation object associated with
+  // |presentation_id| and |presentation_url|.
+  // Creates a new presentation if no presentation with |presentation_id|
+  // exists.
+  virtual void RegisterOffscreenPresentationRoute(
+      const std::string& presentation_id,
+      const GURL& presentation_url,
+      const MediaRoute& route);
+
+  // Returns true if this class has an offscreen presentation with
+  // |presentation_id|.
+  virtual bool IsOffscreenPresentation(const std::string& presentation_id);
+
+  // Returns nullptr if |presentation_id| is not associated with an offscreen
+  // presentation.
+  virtual const MediaRoute* GetRoute(const std::string& presentation_id);
+
  private:
   // Represents an offscreen presentation registered with
   // OffscreenPresentationManager. Contains callback to the receiver to inform
   // it of new connections established from a controller. Contains set of
   // controllers registered to OffscreenPresentationManager before corresponding
   // receiver.
   class OffscreenPresentation {
    public:
     OffscreenPresentation(const std::string& presentation_id,
                           const GURL& presentation_url);
@@ skipping 14 matching lines @@
     // pending controller with |render_frame_id|.
     void UnregisterController(const RenderFrameHostId& render_frame_id);
 
     // Register |receiver_callback| to current offscreen_presentation object.
     // For each controller in |pending_controllers_| map, invoke
     // |receiver_callback| with controller as parameter. Clear
     // |pending_controllers_| map afterwards.
     void RegisterReceiver(
         const content::ReceiverConnectionAvailableCallback& receiver_callback);
 
+    // Register |route| to this class.
+    void RegisterRoute(const MediaRoute& route);
+
    private:
     friend class OffscreenPresentationManagerTest;
     friend class OffscreenPresentationManager;
 
     // Returns false if receiver_callback_ is null and there are no pending
     // controllers.
     bool IsValid() const;
 
     const std::string presentation_id_;
     const GURL presentation_url_;
+    std::unique_ptr<MediaRoute> route_;

[imcheng, 2017/02/24 01:37:46]

What does it mean to have an OffscreenPresentation without a route set? Is this
possible because the object might have been created on the receiver side first?

[zhaobin, 2017/02/24 02:35:33]

Yes. RegisterReceiver() is invoked by receiver's PresentationDispatcher and
PSImpl::SetClient(). RegisterRoute() is invoked by controller's
PSDImpl::OnStartSessionSucceeded(). Order could be random?

[imcheng, 2017/02/24 20:52:25]

Hmm, this almost feels as if we should have a presentation ID to MediaRoute
mapping in MediaRouter instead. It could also help us solve the problem of
deduplicating JoinRoute / ConnectRouteByRouteId. Mark, WDYT?

[mark a. foltz, 2017/03/01 06:26:32]

What if we added a presentationId field to MediaRoute and a method in MR to look
through MediaRoutes for a matching ID?

 
     // Callback to invoke whenever a receiver connection is available.
     content::ReceiverConnectionAvailableCallback receiver_callback_;
 
     // Stores controller information.
     // |controller_connection_ptr|: Mojo::InterfacePtr to
     // blink::PresentationConnection object in controlling frame;
     // |receiver_connection_request|: Mojo::InterfaceRequest to be bind to
     // blink::PresentationConnection object in receiver frame.
     struct ControllerConnection {
@@ skipping 40 matching lines @@
   OffscreenPresentationMap offscreen_presentations_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(OffscreenPresentationManager);
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_OFFSCREEN_PRESENTATION_MANAGER_H_