Cancel timer only on websocket_data receives or sends

This commit prevents erlang messages from keeping a websocket connection
alive. Previously, the timer was canceled upon any activity. Now, the
timeout is only canceled when actual data is sent from the client. The
handler_loop_timeout/1 function is called from websocket_data/4 instead
of handler_before_loop/4. It is also called after every successful reply
in handler_call/4.

1 files changed, 33 insertions, 0 deletions

diff --git a/test/ws_timeout_cancel_handler.erl b/test/ws_timeout_cancel_handler.erl
new file mode 100644
index 0000000..ee75d9b
--- /dev/null
+++ b/test/ws_timeout_cancel_handler.erl
@@ -0,0 +1,33 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+-module(ws_timeout_cancel_handler).
+-behaviour(cowboy_http_handler).
+-behaviour(cowboy_websocket_handler).
+-export([init/3, handle/2, terminate/2]).
+-export([websocket_init/3, websocket_handle/3,
+	websocket_info/3, websocket_terminate/3]).
+
+init(_Any, _Req, _Opts) ->
+	{upgrade, protocol, cowboy_websocket}.
+
+handle(_Req, _State) ->
+	exit(badarg).
+
+terminate(_Req, _State) ->
+	exit(badarg).
+
+websocket_init(_TransportName, Req, _Opts) ->
+	erlang:start_timer(500, self(), should_not_cancel_timer),
+	{ok, Req, undefined, 1000}.
+
+websocket_handle({text, Data}, Req, State) ->
+	{reply, {text, Data}, Req, State};
+websocket_handle({binary, Data}, Req, State) ->
+	{reply, {binary, Data}, Req, State}.
+
+websocket_info(_Info, Req, State) ->
+	erlang:start_timer(500, self(), should_not_cancel_timer),
+	{ok, Req, State}.
+
+websocket_terminate(_Reason, _Req, _State) ->
+	ok.