AWS Broker

:incoming_envelope: Ruby pub-sub on AWS

Background

This lightweight abstraction simplifies pub-sub on AWS's SNS and SQS services. Message processing is not part of this gem - we recommend using Shoryuken in addition to this gem.

Installation

gem 'aws-broker'

Basic Usage

Broker = Aws::Broker
topic = 'topic'
queue = 'queue'
message = { id: 0 }

# subscribe topic to specified queue
Broker.subscribe(topic, queue)

# subscribe topic to default queue (see wiki)
Broker.subscribe(topic)

# publish message to topic
Broker.publish(topic, message)

Rails Usage

Though AWS Broker does not require Rails, an ActiveRecord extension and accompanying RSpec matcher is provided if the project is Rails. This simplifies the process of publishing events for ActiveRecord create, update, and destroy callbacks.

Publishing

# app/models/user.rb
class User < ActiveRecord::Base
  publish_event :create, :update, :destroy
  # optionally override default topic name
  # self.publish_topic = :prefixed_user
end

The above is essentially shorthand for

# app/models/user.rb
class User < ActiveRecord::Base
  after_commit on: :create do
    Broker.publish(:user, event: :create, id: id)
  end
end

Testing

# spec/rails_helper.rb
require 'aws/broker/matchers'

# spec/models/user_spec.rb
describe User do
  context 'publish' do
    subject { User }
    it { should publish_event(:create) }
    it { should publish_event(:update) }
    it { should publish_event(:destroy) }
  end
end

Usage Details

See the wiki for an in-depth overview of usage and configuration options.