wip

lib/ex_webrtc/peer_connection.ex

@@ -293,15 +293,23 @@ defmodule ExWebRTC.PeerConnection do
   defp apply_remote_description(_type, sdp, state) do
     # TODO apply steps listed in RFC 8829 5.10
     media = hd(sdp.media)
-    {:ice_ufrag, ufrag} = ExSDP.Media.get_attribute(media, :ice_ufrag)
-    {:ice_pwd, pwd} = ExSDP.Media.get_attribute(media, :ice_pwd)
 
-    :ok = ICEAgent.set_remote_credentials(state.ice_agent, ufrag, pwd)
-    :ok = ICEAgent.gather_candidates(state.ice_agent)
+    with {:ice_ufrag, ufrag} <- ExSDP.Media.get_attribute(media, :ice_ufrag),
+         {:ice_pwd, pwd} <- ExSDP.Media.get_attribute(media, :ice_pwd),
+         {:ok, transceivers} <- get_transceivers(sdp, state) do
+      :ok = ICEAgent.set_remote_credentials(state.ice_agent, ufrag, pwd)
+      :ok = ICEAgent.gather_candidates(state.ice_agent)
 
+      transceivers = Map.merge(transceivers, state.transceivers)
+      {:ok, %{state | current_remote_desc: sdp, transceivers: transceivers}}
+    else
+      nil -> {:error, :missing_ice_ufrag_or_pwd}
+    end
+  end
+
+  defp get_transceivers(sdp, state) do
     transceivers =
-      sdp.media
-      |> Enum.reduce(%{}, fn media ->
+      Enum.reduce_while(sdp.media, %{}, fn media, transceivers ->
         {:mid, mid} = ExSDP.Media.get_attribute(media, :mid)
         # if there is no direction, the default is sendrecv
         # see RFC 3264, sec. 6.1  
@@ -320,17 +328,15 @@ defmodule ExWebRTC.PeerConnection do
 
         {tr.mid, tr}
       end)
-      |> Map.merge(state.transceivers)
-
-    {:ok, %{state | current_remote_desc: sdp, transceivers: transceivers}}
   end
 
   defp find_or_create_transceiver(mid, direction, transceivers)
        when direction in [:sendrecv, :recvonly] do
-    Enum.find(transceivers, %RTPTransceiver{mid: mid, direction: :recvonly}, fn
-      {nil, tr} when tr.direction == direction -> tr
-      _other -> nil
+    Enum.find(transceivers, {nil, %RTPTransceiver{mid: mid, direction: :recvonly}}, fn
+      {nil, tr} -> tr.direction == direction
+      _other -> false
     end)
+    |> elem(1)
   end
 
   defp find_or_create_transceiver(mid, :sendonly, _transceivers) do