SneakersHandlers

Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file lib/sneakers_handlers. To experiment with that code, run bin/console for an interactive prompt.

TODO: Delete this and the text above, and describe your gem

Installation

Add this line to your application's Gemfile:

gem 'sneakers_handlers'

And then execute:

$ bundle

Or install it yourself as:

$ gem install sneakers_handlers

Usage

The gem introduces two handlers you can use as part of your sneaker workers: SneakersHandlers::DeadLetterHandler and SneakersHandlers::RetryHandler

Using the SneakersHandlers::RetryHandler handler

When defining your worker, you have the following extra options:

x-dead-letter-exchange [required] : The name of the dead-letter exchange where failed messages will be published to.

x-dead-letter-routing-key [required] : The routing key that will be used when dead-lettering a failed message. This value needs to be unique to your application to avoid having the same message delivered to multiple queues. The recommendation it to use the queue name.

max_retry [optional] : The number of times a message will be processed after a rejection.

class MyWorker
  include Sneakers::Worker
  from_queue "my-app.resource_processor",
      durable: true,
      ack: true,
      exchange: "domain_events",
      exchange_type: :topic,
      routing_key: "resources.lifecycle.*",
      handler: Sneakers::Handlers::RetryHandler,
      max_retry: 6,
      arguments: { "x-dead-letter-exchange" => "domain_events.dlx",
                   "x-dead-letter-routing-key" => "my-app.resource_processor" }

  def work(payload)
    ...
  end
end

Using the SneakersHandlers::ExponentialBackoffHandler handler

When defining your worker, you have the following options:

x-dead-letter-exchange [required] : The name of the dead-letter exchange where failed messages will be published to.

x-dead-letter-routing-key [required] : The routing key that will be used when dead-lettering a failed message. This value needs to be unique to your application to avoid having the same message delivered to multiple queues. The recommendation it to use the queue name.

max_retries [optional] : An integer containing the maximum number of times the same messages will be retried. If you don't define this option, 25 is the default.

class MyWorker
  include Sneakers::Worker
  from_queue "my-app.resource_processor",
      durable: true,
      ack: true,
      exchange: "domain_events",
      exchange_type: :topic,
      routing_key: "resources.lifecycle.*",
      handler: SneakersHandlers::ExponentialBackoffHandler,
      max_retries: 10,
      arguments: { "x-dead-letter-exchange" => "domain_events.dlx",
                   "x-dead-letter-routing-key" => "my-app.resource_processor" }

  def work(payload)
    ...
  end
end

Development

After checking out the repository, run bin/setup to install dependencies. Then, run rake to run the tests (you will need to have a real RabbitMQ instance running). You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.