Non-Local Join for Media Router and Presentation API

chrome/browser/media/router/media_router.h

 // 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.
 
 #ifndef CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 67 matching lines @@
   // The caller may pass in nullptr for |web_contents| if tab is not applicable.
   // Each callback in |callbacks| is invoked with a response indicating
   // success or failure, in the order they are listed.
   virtual void CreateRoute(
       const MediaSource::Id& source_id,
       const MediaSink::Id& sink_id,
       const GURL& origin,
       content::WebContents* web_contents,
       const std::vector<MediaRouteResponseCallback>& callbacks) = 0;
 
+  // Joins an existing route identified by |route_id|. This is used for
+  // non-local routes since no Presentation ID is available.
+  // |source|: The source to route to the existing route.
+  // |route_id|: Route ID of the existing route.
+  // |origin|, |web_contents|: Origin and WebContents of the join route request.
+  // Used for validation when enforcing same-origin and/or same-tab scope.
+  // (See CreateRoute documentation).
+  // Each callback in |callbacks| is invoked with a response indicating
+  // success or failure, in the order they are listed.
+  virtual void JoinRouteByRouteId(
+      const MediaSource::Id& source,

[mark a. foltz, 2015/12/03 19:24:23]

source_id for consistency with CreateRoute

[matt.boetger, 2015/12/15 19:21:20]

Done.

+      const MediaRoute::Id& route_id,

[mark a. foltz, 2015/12/03 19:24:23]

Note, the route_id should include the source_id (or the source could be looked
up it).  But fine to keep it here for consistency with CreateRoute() and
JoinRoute().

[mark a. foltz, 2015/12/09 00:48:16]

You can ignore this comment.

[matt.boetger, 2015/12/15 19:21:20]

Done.

[matt.boetger, 2015/12/15 19:21:20]

Done.

+      const GURL& origin,
+      content::WebContents* web_contents,
+      const std::vector<MediaRouteResponseCallback>& callbacks) = 0;
+
   // Joins an existing route identified by |presentation_id|.
   // |source|: The source to route to the existing route.
   // |presentation_id|: Presentation ID of the existing route.
   // |origin|, |web_contents|: Origin and WebContents of the join route request.
   // Used for validation when enforcing same-origin and/or same-tab scope.
   // (See CreateRoute documentation).
   // Each callback in |callbacks| is invoked with a response indicating
   // success or failure, in the order they are listed.
   virtual void JoinRoute(
       const MediaSource::Id& source,
       const std::string& presentation_id,

[mark a. foltz, 2015/12/03 19:24:23]

I still think this API is weird, but I think I understand why it is the way it
is.  Basically the "presentation id" concept is currently not defined across
devices in Chrome at present.  Instead we allow an MRP to create a non local
route and assign it a fake route id which is used here to implement manual join.

I think one long term fix here is to define a presentation id for non-local
presentations that can be advertised by the MRP. Then we can call JoinRoute with
either kind of id.  For local presentations we automatically join, for non-local
we go through the new flow you're adding.

If there's agreement, then we should update crbug.com/510297 and add a TODO here
referencing it.

[matt.boetger, 2015/12/15 19:21:20]

If we're going to a new method, 'connectRouteByRouteId' I don't see why we need
to define a special presentation id for non-local joins - in fact, we can get
rid of the special "non-local-join" fake presentation id.  This probably needs
to be thought through a little more after we see the refactoring.    

       const GURL& origin,
       content::WebContents* web_contents,
       const std::vector<MediaRouteResponseCallback>& callbacks) = 0;
 
   // Closes the media route specified by |route_id|.
   virtual void CloseRoute(const MediaRoute::Id& route_id) = 0;
 
   // Posts |message| to a MediaSink connected via MediaRoute with |route_id|.
   virtual void SendRouteMessage(const MediaRoute::Id& route_id,
                                 const std::string& message,
@@ skipping 98 matching lines @@
       LocalMediaRoutesObserver* observer) = 0;
 
   // Removes the LocalMediaRoutesObserver |observer|.
   virtual void UnregisterLocalMediaRoutesObserver(
       LocalMediaRoutesObserver* observer) = 0;
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_H_