%% Feel free to use, reuse and abuse the code in this file.
-module(echo_protocol).
-behaviour(ranch_protocol).
-export([start_link/4]).
-export([init/3]).
start_link(Ref, _Socket, Transport, Opts) ->
Pid = spawn_link(?MODULE, init, [Ref, Transport, Opts]),
{ok, Pid}.
init(Ref, Transport, _Opts = []) ->
{ok, Socket} = ranch:handshake(Ref),
loop(Socket, Transport).
loop(Socket, Transport) ->
case Transport:recv(Socket, 0, 5000) of
{ok, Data} when Data =/= <<4>> ->
Transport:send(Socket, Data),
loop(Socket, Transport);
_ ->
ok = Transport:close(Socket)
end.