SneakersExponentialRetry

Exponential Retry Handler for Sneakers that just works.

Usage

Configure your Sneakers by the following:

require 'sneakers_exponential_retry'

Sneakers.configure :handler => SneakersExponentialRetry::Handler,
                   :handler_options => {
                     :max_retry_count => 3,
                     :logger => Sneakers.logger
                   },
                   :exchange => 'MyExchangeName',
                   :exchange_type => :topic

Options:

• exchange: Exchange name to be used, required for SneakersExponentialRetry
• handler_options:
  • max_retry_count: (optional) Max retry count, default to 14
  • logger: (optional) logger instance, default to nil, which would not log anything related to retrying.

Installation

Add this line to your application's Gemfile:

gem 'sneakers_exponential_retry'

And then execute:

$ bundle

Or install it yourself as:

$ gem install sneakers_exponential_retry

How it works:

(SneakersExponentialRetry is inspired by this blogpost)

SneakersExponentialRetry handles the behavior of retrying failed jobs exponentially by:

1. On initializing:

   • Create a retry exchange, which is named as #{queue_name}-retry-ex
   • Create a retry queue, which is named as #{queue_name}-retry-queue
   • Set the x-dead-letter-exchange of retry queue to the original job exchange
   • Bind the retry queue to the retry exchange

2. Whenever a job fails, SneakersExponentialRetry would:

   • if retry count <= max_retry_count
   • publish the job to retry exchange, with an exponential expiration timeout
   • the retry exchange would push the job into our retry queue
   • after the timeout, the job would be published back to the dead-letter-exchange of the retry queue, which is our original exchange, so that the job would be retried

• if retry count > max_retry_count
  • reject the job

Testing:

Run tests by:

$ bundle exec rspec

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. 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.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/mz026/sneakers_exponential_retry. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.