gistfile1.erl

% snippet from pubsub_srv.erl
%-----------
start_link() -> 
  {ok,PID} = eredis_sub:start_link(),
  register(eredispid,PID),
  _Receiver = spawn_link(fun () ->
                                  eredis_sub:controlling_process(PID),
                                  receiver(PID)
                          end),
  io:format("Eredis server started~n"),
  {ok, PID}.

receiver(Sub) ->
    receive
        Msg ->
            io:format("received ~p~n", [Msg]),
            eredis_sub:ack_message(Sub),
            ?MODULE:receiver(Sub)
    end.

subscribe_channel(Channel) -> 
   io:format("received request to subscribe to ~p~n",[Channel]),
   Sub = whereis(eredispid),
   io:format("Found PID ~p for subscription~n",[Sub]),
   eredis_sub:subscribe(Sub, [Channel]).


%snippet from cowboy_callback.erl
%----------------------------------
handle(Req,State) -> 
    case cowboy_http_req:qs_val(<<"channel">>,Req) of 
    	{undefined,_Req2} -> 
    		io:format("Sorry missing channel query param"),
    		{ok, Req3} = cowboy_http_req:reply(200, [{'Content-Type', <<"text/html">>}],<<"Sorry, invalid channel">>,Req);
    	{Channel,_Req2} -> 
    		io:format("Subscribing to channel ~p~n",[Channel]),
    		erltest1_pubsub_srv:subscribe_channel(Channel),
    		{ok, Req3} = cowboy_http_req:reply(200, [{'Content-Type', <<"text/html">>}],<<"You subscribed to a channel!">>,Req);
    	_ -> 
    		io:format("Dont know what to do~n"),
    		{ok, Req3} = cowboy_http_req:reply(200, [{'Content-Type', <<"text/html">>}],<<"Sorry dont know what to do">>,Req)
    end,
	{ok, Req3, State}.