add websocket example

examples/websocket/src/ws_handler.erl

@@ -0,0 +1,29 @@
+-module(ws_handler).
+-behaviour(cowboy_websocket_handler).
+
+-export([init/3]).
+-export([websocket_init/3]).
+-export([websocket_handle/3]).
+-export([websocket_info/3]).
+-export([websocket_terminate/3]).
+
+init({tcp, http}, _Req, _Opts) ->
+	{upgrade, protocol, cowboy_websocket}.
+
+websocket_init(_TransportName, Req, _Opts) ->
+	erlang:start_timer(1000, self(), <<"Hello!">>),
+	{ok, Req, undefined_state}.
+
+websocket_handle({text, Msg}, Req, State) ->
+	{reply, {text, << "That's what she said! ", Msg/binary >>}, Req, State};
+websocket_handle(_Data, Req, State) ->
+	{ok, Req, State}.
+
+websocket_info({timeout, _Ref, Msg}, Req, State) ->
+	erlang:start_timer(1000, self(), <<"How' you doin'?">>),
+	{reply, {text, Msg}, Req, State};
+websocket_info(_Info, Req, State) ->
+	{ok, Req, State}.
+
+websocket_terminate(_Reason, _Req, _State) ->
+	ok.