Riak postcommit ZeroMQ publisher

riak_zmq.erl

-module(riak_zmq).

-export([postcommit_publish/1, get_zmq_publisher/0, zmq_publisher/0, zmq_publisher/1]).

postcommit_publish(RObj) ->
    Body = riak_object:get_value(RObj),
    {ok, Pid} = get_zmq_publisher(),
    Pid ! {send, Body}.

get_zmq_publisher() ->
    case pg2:get_closest_pid([zmq]) of
        {error, {no_such_group, _}} ->
            pg2:create([zmq]),
            get_zmq_publisher();
        {error, {no_process, _}} ->
            Pid = spawn(?MODULE, zmq_publisher, []),
            pg2:join([zmq], Pid),
            {ok, Pid};
        Pid ->
            {ok, Pid}
    end.

zmq_publisher() ->
    {ok, _Pid} = zmq:start_link(),
    {ok, Socket} = zmq:socket(pub),
    zmq:bind(Socket, "tcp://127.0.0.1:5550"),
    zmq_publisher(Socket).

zmq_publisher(Socket) ->
    receive
        {send, Msg} -> zmq:send(Socket, Msg), zmq_publisher(Socket)
    end.

Hi, could you explain please what this is for, for the newbbie I am. I am appealed by riak for availability on one hand, and by 0MQ for ease of use and scallability on the other hand. Is riak_zmq the glue between both ?