add websocket example

examples/websocket/src/toppage_handler.erl

@@ -0,0 +1,24 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+-module(toppage_handler).
+
+-export([init/3]).
+-export([handle/2]).
+-export([terminate/3]).
+
+init(_Transport, Req, []) ->
+	{ok, Req, undefined}.
+
+handle(Req, State) ->
+	Html = get_html(),
+	{ok, Req2} = cowboy_req:reply(200, [], Html, Req),
+	{ok, Req2, State}.
+
+terminate(_Reason, _Req, _State) ->
+	ok.
+
+get_html() ->
+	{ok, Cwd} = file:get_cwd(),
+	Filename =filename:join([Cwd, "priv", "html_ws_client.html"]),
+	{ok, Binary} = file:read_file(Filename),
+	Binary.

examples/websocket/src/websocket.app.src

@@ -0,0 +1,15 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+{application, websocket, [
+	{description, "Cowboy websocket example."},
+	{vsn, "1"},
+	{modules, []},
+	{registered, []},
+	{applications, [
+		kernel,
+		stdlib,
+		cowboy
+	]},
+	{mod, {websocket_app, []}},
+	{env, []}
+]}.

examples/websocket/src/websocket.erl

@@ -0,0 +1,12 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+-module(websocket).
+
+%% API.
+-export([start/0]).
+
+start() ->
+	ok = application:start(crypto),
+	ok = application:start(ranch),
+	ok = application:start(cowboy),
+	ok = application:start(websocket).

examples/websocket/src/websocket_app.erl

@@ -0,0 +1,24 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+%% @private
+-module(websocket_app).
+-behaviour(application).
+
+%% API.
+-export([start/2]).
+-export([stop/1]).
+
+%% API.
+start(_Type, _Args) ->
+	Dispatch = cowboy_router:compile([
+		{'_', [
+			{"/", toppage_handler, []},
+			{"/websocket", ws_handler, []}
+		]}
+	]),
+	{ok, _} = cowboy:start_http(http, 100, [{port, 8080}], 
+		[{env, [{dispatch, Dispatch}]}]),
+	websocket_sup:start_link().
+
+stop(_State) ->
+	ok.

examples/websocket/src/websocket_sup.erl

@@ -0,0 +1,23 @@
+%% Feel free to use, reuse and abuse the code in this file.
+
+%% @private
+-module(websocket_sup).
+-behaviour(supervisor).
+
+%% API.
+-export([start_link/0]).
+
+%% supervisor.
+-export([init/1]).
+
+%% API.
+
+-spec start_link() -> {ok, pid()}.
+start_link() ->
+	supervisor:start_link({local, ?MODULE}, ?MODULE, []).
+
+%% supervisor.
+
+init([]) ->
+	Procs = [],
+	{ok, {{one_for_one, 10, 10}, Procs}}.

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.