Apply requested changes

Author: LVala

examples/echo/.DS_Store

@@ -61,6 +61,8 @@ defmodule ExWebRTC.PeerConnection do
   """
   @type connection_state() :: :closed | :failed | :disconnected | :new | :connecting | :connected
 
+  @twcc_uri "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"
+
   #### API ####
   @doc """
   Returns a list of all running peer connections.
@@ -734,10 +736,7 @@ defmodule ExWebRTC.PeerConnection do
     case transceiver do
       %RTPTransceiver{} ->
         {packet, state} =
-          case Map.fetch(
-                 state.config.video_rtp_hdr_exts,
-                 "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"
-               ) do
+          case Map.fetch(state.config.video_rtp_hdr_exts, @twcc_uri) do
             {:ok, %{id: id}} ->
               twcc =
                 ExRTP.Packet.Extension.TWCC.new(state.sent_packets)
@@ -818,20 +817,16 @@ defmodule ExWebRTC.PeerConnection do
   def handle_info({:dtls_transport, _pid, {:rtp, data}}, state) do
     with {:ok, demuxer, mid, packet} <- Demuxer.demux(state.demuxer, data),
          {idx, %RTPTransceiver{} = t} <- find_transceiver(state.transceivers, mid) do
-      %{twcc_recorder: twcc_recorder} = state
-
+      # we always update the ssrc's for the one's from the latest packet
+      # although this is not a necessity, the feedbacks are transport-wide
       twcc_recorder = %TWCCRecorder{
-        twcc_recorder
+        state.twcc_recorder
         | media_ssrc: packet.ssrc,
           sender_ssrc: t.sender.ssrc
       }
 
       twcc_recorder =
-        with {:ok, %{id: id}} <-
-               Map.fetch(
-                 state.config.video_rtp_hdr_exts,
-                 "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"
-               ),
+        with {:ok, %{id: id}} <- Map.fetch(state.config.video_rtp_hdr_exts, @twcc_uri),
              {:ok, raw_ext} <- ExRTP.Packet.fetch_extension(packet, id),
              {:ok, %{sequence_number: seq_no}} <- ExRTP.Packet.Extension.TWCC.from_raw(raw_ext) do
           TWCCRecorder.record_packet(twcc_recorder, seq_no)
@@ -870,8 +865,13 @@ defmodule ExWebRTC.PeerConnection do
         notify(state.owner, {:rtcp, packets})
 
       {:error, _res} ->
-        <<2::2, _::1, count::5, ptype::8, _::binary>> = data
-        Logger.warning("Failed to decode RTCP packet, type: #{ptype}, count: #{count}")
+        case data do
+          <<2::2, _::1, count::5, ptype::8, _::binary>> ->
+            Logger.warning("Failed to decode RTCP packet, type: #{ptype}, count: #{count}")
+
+          _ ->
+            Logger.warning("Failed to decode RTCP packet, packet is too short")
+        end
     end
 
     {:noreply, state}

examples/save_to_file/.DS_Store

@@ -180,11 +180,11 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorder do
     end
   end
 
-  @spec get_feedback(t()) :: {t(), [CC.t()]}
+  @spec get_feedback(t()) :: {[CC.t()], t()}
   def get_feedback(recorder, feedbacks \\ [])
 
   def get_feedback(%{base_seq_no: seq_no, end_seq_no: seq_no} = recorder, feedbacks),
-    do: {recorder, Enum.reverse(feedbacks)}
+    do: {Enum.reverse(feedbacks), recorder}
 
   def get_feedback(recorder, feedbacks) do
     %__MODULE__{

examples/send_from_file/.DS_Store

@@ -197,7 +197,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
           timestamps: timestamps
       }
 
-      assert {recorder, [feedback]} = TWCCRecorder.get_feedback(recorder)
+      assert {[feedback], recorder} = TWCCRecorder.get_feedback(recorder)
 
       assert %CC{
                base_sequence_number: @seq_no,
@@ -209,7 +209,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
              } = feedback
 
       # no new packets -> no feedback
-      assert {_recorder, []} = TWCCRecorder.get_feedback(recorder)
+      assert {[], _recorder} = TWCCRecorder.get_feedback(recorder)
     end
 
     test "packets out of order, with gaps" do
@@ -231,7 +231,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
           timestamps: timestamps
       }
 
-      assert {recorder, [feedback]} = TWCCRecorder.get_feedback(recorder)
+      assert {[feedback], recorder} = TWCCRecorder.get_feedback(recorder)
 
       symbols = [
         :small_delta,
@@ -252,7 +252,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
                recv_deltas: [246, 5, -17, -8, 25]
              } = feedback
 
-      assert {_recorder, []} = TWCCRecorder.get_feedback(recorder)
+      assert {[], _recorder} = TWCCRecorder.get_feedback(recorder)
     end
 
     test "mixed chunks" do
@@ -266,7 +266,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
           TWCCRecorder.record_packet(recorder, i)
         end)
 
-      assert {recorder, [feedback]} = TWCCRecorder.get_feedback(recorder)
+      assert {[feedback], recorder} = TWCCRecorder.get_feedback(recorder)
 
       assert %CC{
                base_sequence_number: @seq_no,
@@ -288,7 +288,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
 
       assert length(deltas) == packet_num - 1
 
-      assert {_recorder, []} = TWCCRecorder.get_feedback(recorder)
+      assert {[], _recorder} = TWCCRecorder.get_feedback(recorder)
     end
 
     test "split into two feedbacks" do
@@ -303,7 +303,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
       timestamps = Map.update!(recorder.timestamps, base_no2, &(&1 + 35_000))
       recorder = %{recorder | timestamps: timestamps}
 
-      assert {recorder, [feedback1, feedback2]} = TWCCRecorder.get_feedback(recorder)
+      assert {[feedback1, feedback2], recorder} = TWCCRecorder.get_feedback(recorder)
 
       assert %CC{
                base_sequence_number: @seq_no,
@@ -327,7 +327,7 @@ defmodule ExWebRTC.PeerConnection.TWCCRecorderTest do
       refute_in_delta ref_time1, ref_time2, 133
       assert_in_delta ref_time1, ref_time2, 143
 
-      assert {_recorder, []} = TWCCRecorder.get_feedback(recorder)
+      assert {[], _recorder} = TWCCRecorder.get_feedback(recorder)
     end
   end
 end