Experimental bridge between RabbitMQ and Redis implemented as a RabbitMQ plugin.

Introduction
------------

This plugin moves messages between RabbitMQ and Redis Pub/Sub (http://redis.io/topics/pubsub) using erldis.
It was inspired by RabbitMQ-shovel and shares the same idea with the exception 
that it connects Redis pub/sub channels to RabbitMQ queues or exchanges.

For building see instructions at:
http://www.rabbitmq.com/plugin-development.html

Configuration
-------------

The plugin is configured using rabbitmq.config file that has a structure 
like this:
[{rabbit, [rabbit-settings]},
 {rabbit_redis, [rabbitmq-redis-plugin-settings]}
].

Example of rabbitmq.config with rabbitmq-redis plugin:
[{rabbit_redis, 
  [{bridges, [
% subscribes to redis channel "foo" and publishes all received messages 
% to rabbitmq exchange "quux" with routing_key equals to redis channel ("foo")
              [{name, subsribe_bridge},
               {type, subscribe},
               {redis, [{host, "localhost"},
                        {port, 6379},
                        {channels, [<<"foo">>]}]},
               {rabbit, [{declarations, [{'exchange.declare',
                                          [{exchange, <<"quux">>},
                                           auto_delete
                                          ]}]},
                         {publish_fields, [{exchange, <<"quux">>}]}]}],
% consumes messages from rabbitmq queue "foo" and publishes them 
% to redis channel with name equals to message routing_key
              [{name, publish_bridge},
               {type, publish},
               {redis, [{host, "localhost"},
                        {port, 6379}]},
               {rabbit, [{declarations, [{'queue.declare', 
                                          [{queue, <<"foo">>},
                                           auto_delete]}]},
                         {bindings, [{'queue.bind', 
                                          [{queue, <<"foo">>},
                                           {exchange, <<"quux">>},
                                           {routing_key, <<"foo">>}]}]},
                         {queue, <<"foo">>}]}]
             ]}]}].

Note that this configuration will create short-circuit for messages 
in queue "foo" making them bounce between rabbit and redis infinitely.


TODO
----

 - handle redis connection failures
 - handle rabbit channel flow events
 - support psubscribe redis command
 - consider merging with rabbitmq-shovel