REVIEW

INTRO

REVIEW is a regular Erlang application.

HEADER

Picture 1. HOW TO SET UP BOTH APP AND SUP IN ERLANG


 -module(review).
 -behaviour(supervisor).
 -behaviour(application).
 -export([init/1, start/0, start/2, stop/1, main/1]).
 -compile(export_all).

OTP

Note that suring start you should specify mauth module. Dafault implementation performs client topic autosubscription.

Picture 2. Implements Erlang/OTP service API


 init([])   -> {ok, {{one_for_one, 5, 10}, [spec()]}}.
 start()    -> start(normal,[]).
 start(_,_) -> emqttd_access_control:register_mod(auth, n2o_auth, [[]], 9998),
               supervisor:start_link({local,review},review,[]).
 stop(_)    -> ok.

MOCHIWEB

REVIEW application uses MOCHIWEB as static HTTP server and as WebSocket proxy to MQTT server.

Picture 3. MOCHIWEB setup


 spec()     ->
    Acceptors  = application:get_env(?MODULE, acceptors,   4),
    Clients    = application:get_env(?MODULE, max_clients, 512),
    Protocol   = application:get_env(?MODULE, protocol,    http),
    Port       = application:get_env(?MODULE, port,        8000),
    Options    = [{max_clients, Clients}, {acceptors, Acceptors}],
    Args       = [{mochiweb, handle, [docroot()]}],
    mochiweb:child_spec(Protocol, Port, Options, Args).

 docroot() ->
    {file, Here} = code:is_loaded(?MODULE),
    Dir = filename:dirname(filename:dirname(Here)),
    Root = application:get_env(?MODULE, "statics_root", "priv/static"),
    filename:join([Dir, Root]).