say_tcp_server.erl

-module(say_tcp_server).
-behaviour(gen_server).

-export([start_link/1]).
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, code_change/3, terminate/2]).

-record(state, {socket}).

start_link(Socket) ->
  gen_server:start_link(?MODULE, Socket, []).

init(Socket) ->
  gen_server:cast(self(), accept),
  {ok, #state{socket=Socket}}.

handle_cast(accept, State = #state{socket=ListenSocket}) ->
  {ok, AcceptSocket} = gen_tcp:accept(ListenSocket),
  say_tcp_sup:start_socket(),
  {noreply, State#state{socket=AcceptSocket}};
handle_cast(_, State) ->
  {noreply, State}.

handle_info({tcp, Socket, Msg}, State) ->
  [Command|Args] = say_command_parser:from_redis(Msg),
  Data = say_command:run(Command, Args),
  ParsedData = say_command_parser:to_redis(Data),
  send(Socket, ParsedData),
  {noreply, State};
handle_info({tcp_closed, _Socket}, State) -> {stop, normal, State};
handle_info({tcp_error, _Socket, _}, State) -> {stop, normal, State};
handle_info(E, State) ->
  lager:debug("unexpected: ~p~n", [E]),
  {noreply, State}.

handle_call(_E, _From, State) -> {noreply, State}.
terminate(_Reason, _Tab) -> ok.
code_change(_OldVersion, Tab, _Extra) -> {ok, Tab}.

send(Socket, Str) ->
  ok = gen_tcp:send(Socket, Str),
  ok = inet:setopts(Socket, [{active, once}]),
  ok.