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An application that simplifies writing RabbitMQ producers and consumers.

Typically, a client workflow is as follows:

- Establish a connection to a broker
- Create a new channel within the open connection
- Execute AMQP commands with a channel such as sending and receiving messages, creating exchanges and queue or defining routing rules between exchanges and queues
- When no longer required, close the channel and the connection

Vent encapsulates this workflow and delegates the consumer specific-logic to a custom `handler` behaviour.

## Configuration

RabbitMQ configuration:

    {host, "localhost"},                                # defaults to 'localhost'
    {port, 5672},                                       # defaults to 5672
    {username, "user"},                                 # optional
    {password, "pass"},                                 # optional
    {virtual_host, <<"prod">>},                         # required
    {publish_exchange, <<"publish_exchange">>}          # required

## Publishers

The serialization format is assumed to be JSON.

To publish a message:

    vent_publisher:publish(Exchange, Topic, Payload).

Publisher configuration:

    {publish_chunk_size, 20}                            # defaults to 20

## Subscribers

A subscriber `handler` should be created for every subscription.  The behaviour
consists of the following callbacks:

    callback init() ->
       {ok, state()}.
    callback handle(term(), state()) ->
       {ok, state()} |
       {requeue, term(), state()} |
       {requeue, number(), term(), state()} |
       {drop, term(), state()}.
    callback terminate(state()) ->

An inert `vent_debug_handler` is already provided that will log every message
that it consumes.

Every subscription should be configured together with its handler:

    {n_workers, 1},                                     # defaults to 5
    {prefetch_count, 2},                                # defaults to 2
    {exchange, <<"exchange">>},                         # required
    {dead_letter_exchange, <<"dl_exchange">>},          # required
    {error_exchange, <<"errors">>},                     # required
    {error_routing_key, <<"error_routing_key">>},       # required
    {queue, <<"vent:queue">>},                          # required
    {message_ttl, 300000},                              # defaults to infinite
    {handler, vent_debug_handler}]                      # defaults to vent_debug_handler

Note that more than one subscriber may be registered.

         [{vent_subscriber, ...config for 1st subscriber},
          {vent_subscriber, ...config for 2nd subscriber}]}

## Build

$ rebar3 compile

In order to run tests...{to do}

## Release
$ rebar3 release