pdcarv / msgr

A Rails-like Messaging Framework.

Msgr: Rails-like Messaging Framework

You know it and you like it. Using Rails you can just declare your routes and create a controller. That's all you need to process requests.

With Msgr you can do the same for asynchronous AMQP messaging. Just define your routes, create your consumer and watch you app processing messages.

Note: Msgr is still under heavy development.

Installation

Add this line to your application's Gemfile:

gem 'msgr'

And then execute:

$ bundle

Or install it yourself as:

$ gem install msgr

Usage

After adding 'msgr' to your gemfile create a config/rabbitmq.yml like this:

common: &common
  uri: amqp://localhost/

test:
  <<: *common

development:
  <<: *common

production:
  <<: *common

Specify your messaging routes in config/msgr.rb:

route 'local.test.index', to: 'test#index'
route 'local.test.another_action', to: 'test#another_action'

Create your consumer in app/consumers:

class TestConsumer < Msgr::Consumer
  def index
    data = { fuubar: 'abc' }

    publish data, to: 'local.test.another_action'
  end

  def another_action
    puts "#{payload.inspect}"
  end
end

Use Msgr.publish in to publish a message:

class TestController < ApplicationController
  def index
    @data = { abc: 'abc' }

    Msgr.publish @data, to: 'local.test.index'

    render nothing: true
  end
end

Msgr and fork web server like unicorn

Per default msgr opens the rabbitmq connect when rails is loaded. If you use a multi-process web server that preloads the application (like unicorn) will lead to unexpected behavior. In this case adjust config/rabbitmq.yml and adjust autostart = false:

common: &common
  uri: amqp://localhost/
  autostart: false

And call inside each worker Msgr.start - e.g. in an after-fork block

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request