dont crash if to field is missing

Author: facundoolano

src/webrtc_ws_handler.erl

@@ -51,16 +51,19 @@ websocket_handle({text, Text}, State = #{authenticated := true,
                                          peer_id := ThisPeer}) ->
   lager:debug("Received text frame ~p", [Text]),
 
-  %% TODO reply error if `to` is missing
-  Message = #{to := OtherPeer} = json_decode(Text),
-  %% crash if room doesn't match
-  {Pid, {_Username, _PeerId, Room}} = syn:find_by_key(OtherPeer, with_meta),
-
-  %% extend message with this peer id before sending
-  Message2 = Message#{from => ThisPeer},
-  Pid ! {text, json_encode(Message2)},
-
-  {ok, State};
+  case json_decode(Text) of
+    #{to := OtherPeer} = Message ->
+      %% crash if room doesn't match
+      {Pid, {_Username, _PeerId, Room}} = syn:find_by_key(OtherPeer, with_meta),
+
+      %% extend message with this peer id before sending
+      Message2 = Message#{from => ThisPeer},
+      Pid ! {text, json_encode(Message2)},
+
+      {ok, State};
+    _ ->
+      {reply, reply_text(invalid_message), State}
+  end;
 
 websocket_handle(Frame, State) ->
   lager:warning("Received non text frame ~p~p", [Frame, State]),

test/webrtc_ws_handler_SUITE.erl

@@ -95,6 +95,9 @@ join_and_send_message(Config) ->
   {ok, #{<<"event">> := <<"left">>}} = ws_client:recv(Conn1),
   {ok, #{<<"event">> := <<"left">>}} = ws_client:recv(Conn3),
 
+  %% fails without `to` field
+  {ok, #{<<"event">> := <<"invalid_message">>}} = ws_client:send(Conn1, #{<<"event">> => <<"bye!">>}),
+
   ok.
 
 auth_failure(Config) ->