Current version

0.5.0

Sevak gem makes it easy to send and receive messages from rabbitmq queues. It is built on top of the bunny gem. It also supports delayed queuing using rabbitmq delayed exchange plugin

Durable option is enabled for all the queues to have persisting queues.

Dependencies

• rabbitmq delayed exchange plugin:

To install this plugin:

1. Download the latest build for the plugin from here
2. Enable the plugin using command:

rabbitmq-plugins enable rabbitmq_delayed_message_exchange

Installation

gem install sevak

Make sure the rabbitmq server is running

You can either install and run the rabbitmq server from the appropriate package for your os or you can run the preconfigured docker image for local testing.

The image can be found here.

https://hub.docker.com/r/deepakkumarnd/sevak/

You can run the rabbitmq by doing the following step

docker pull deepakkumarnd/sevak
docker run -d --name rabbitmq_test -p 15672:15672 -p 5672:5672 deepakkumarnd/sevak

After this you will be able to access the management console by going to http://localhost:15672. You can login using guest, guest as username and password.

Configuration

Create a file under config/initializers and add following lines to that file:

Sevak.configure do |f|
    f.host = 'localhost'
    f.port = '5672'
    f.user = 'username'
    f.password = 'password'
    f.prefetch_count = 10
end

Usage:

Publishing to a queue

To publish any message to a queue use the following syntax:

Sevak::Publisher.publish(*queue_name*, *message*)

If the queue is not present already it will be created automatically.

Example:

Sevak::Publisher.delayed_publish('sms', message = { name: 'Deepak', msisdn: '9078657543' })

Publishing to a queue with a delay

To publish any message to a queue with some delay use the following syntax:

Sevak::Publisher.publish(*queue_name*, *message*, *delay in milliseconds*)

Example:

Sevak::Publisher.delayed_publish('sms', message = { name: 'Deepak', msisdn: '9078657543' }, 10000)

This will publish the message to an exchange which will route the message to the specified queue with a delay of 10 seconds.

Receiving messages from the queue

To receive message from this queue and process the message create a consumer file for each queue in your project under app/consumers.

class SmsConsumer < Sevak::Consumer

    queue_name 'sms'

    def run(message)
        *process the message*
    end

    ..
end

The return status can have three values :ok, :error, :retry.

Run the preconfigured docker container for testing purpose

https://hub.docker.com/r/deepakkumarnd/sevak/

docker pull deepakkumarnd/sevak docker run -d --name rabbitmq_test -p 15672:15672 -p 5672:5672 deepakkumarnd/sevak