Emit track_ended event

Author: mickel8

lib/ex_webrtc/peer_connection.ex

@@ -441,7 +441,8 @@ defmodule ExWebRTC.PeerConnection do
         if tr.stopping do
           {:reply, :ok, state}
         else
-          tr = RTPTransceiver.stop_sending_and_receiving(tr)
+          on_track_ended = on_track_ended(state.owner, tr.receiver.track.id)
+          tr = RTPTransceiver.stop_sending_and_receiving(tr, on_track_ended)
           transceivers = List.replace_at(state.transceivers, idx, tr)
           state = %{state | transceivers: transceivers}
           state = update_negotiation_needed(state)
@@ -1026,7 +1027,11 @@ defmodule ExWebRTC.PeerConnection do
 
     tr = process_remote_track(tr, direction, owner)
     tr = if sdp_type == :answer, do: %RTPTransceiver{tr | current_direction: direction}, else: tr
-    tr = if SDPUtils.is_rejected(mline), do: RTPTransceiver.stop(tr), else: tr
+
+    tr =
+      if SDPUtils.is_rejected(mline),
+        do: RTPTransceiver.stop(tr, on_track_ended(owner, tr.receiver.track.id)),
+        else: tr
 
     case idx do
       nil ->
@@ -1210,5 +1215,7 @@ defmodule ExWebRTC.PeerConnection do
     if ssrc in ssrcs, do: do_generate_ssrc(ssrcs, max_attempts - 1), else: ssrc
   end
 
+  defp on_track_ended(owner, track_id), do: fn -> notify(owner, {:track_ended, track_id}) end
+
   defp notify(pid, msg), do: send(pid, {:ex_webrtc, self(), msg})
 end

lib/ex_webrtc/rtp_transceiver.ex

@@ -162,17 +162,22 @@ defmodule ExWebRTC.RTPTransceiver do
     %__MODULE__{transceiver | mid: mid, sender: sender}
   end
 
-  @spec stop(t()) :: t()
-  def stop(transceiver) do
-    tr = if transceiver.stopping, do: transceiver, else: stop_sending_and_receiving(transceiver)
+  @spec stop(t(), (-> term())) :: t()
+  def stop(transceiver, on_track_ended) do
+    tr =
+      if transceiver.stopping,
+        do: transceiver,
+        else: stop_sending_and_receiving(transceiver, on_track_ended)
+
     # should we reset stopping or leave it as true?
     %__MODULE__{tr | stopped: true, stopping: false, current_direction: nil}
   end
 
-  @spec stop_sending_and_receiving(t()) :: t()
-  def stop_sending_and_receiving(transceiver) do
+  @spec stop_sending_and_receiving(t(), (-> term())) :: t()
+  def stop_sending_and_receiving(transceiver, on_track_ended) do
     # TODO send RTCP BYE for each RTP stream
     # TODO stop receiving media
+    on_track_ended.()
     %__MODULE__{transceiver | direction: :inactive, stopping: true}
   end
 

test/ex_webrtc/peer_connection_test.exs

@@ -446,9 +446,10 @@ defmodule ExWebRTC.PeerConnectionTest do
   describe "stop_transceiver/2" do
     test "before the first offer" do
       {:ok, pc1} = PeerConnection.start_link()
-      {:ok, _pc2} = PeerConnection.start_link()
       {:ok, tr} = PeerConnection.add_transceiver(pc1, :audio)
       :ok = PeerConnection.stop_transceiver(pc1, tr.id)
+      assert_receive {:ex_webrtc, ^pc1, {:track_ended, track_id}}
+      assert tr.receiver.track.id == track_id
       {:ok, offer} = PeerConnection.create_offer(pc1)
       sdp = ExSDP.parse!(offer.sdp)
       assert sdp.media == []
@@ -465,6 +466,10 @@ defmodule ExWebRTC.PeerConnectionTest do
 
       :ok = PeerConnection.stop_transceiver(pc1, tr.id)
 
+      assert_receive {:ex_webrtc, ^pc1, :negotiation_needed}
+      assert_receive {:ex_webrtc, ^pc1, {:track_ended, track_id}}
+      assert tr.receiver.track.id == track_id
+
       assert [
                %RTPTransceiver{
                  current_direction: :sendonly,
@@ -474,8 +479,6 @@ defmodule ExWebRTC.PeerConnectionTest do
                }
              ] = PeerConnection.get_transceivers(pc1)
 
-      assert_receive {:ex_webrtc, ^pc1, :negotiation_needed}
-
       {:ok, offer} = PeerConnection.create_offer(pc1)
       :ok = PeerConnection.set_local_description(pc1, offer)
 
@@ -493,6 +496,8 @@ defmodule ExWebRTC.PeerConnectionTest do
       # immediately after setting remote description
       :ok = PeerConnection.set_remote_description(pc2, offer)
 
+      assert_receive {:ex_webrtc, ^pc2, {:track_ended, _track_id}}
+
       assert [
                %RTPTransceiver{
                  current_direction: nil,