Middleware

Basic middleware

class MyMiddleware
  def call(worker_instance, queue, sqs_msg, body)
    puts 'Before work'
    yield
    puts 'After work'
  end
end

Registering a global middleware

Shoryuken.configure_server do |config|
  config.server_middleware do |chain|
    chain.add MyMiddleware
    # chain.remove MyMiddleware
    # chain.add MyMiddleware, foo: 1, bar: 2
    # chain.insert_before MyMiddleware, MyMiddlewareNew
    # chain.insert_after MyMiddleware, MyMiddlewareNew
  end
end

Registering per worker middleware

class MyWorker
  include Shoryuken::Worker

  def perform(sqs_mg, body)
    # ...
  end

  server_middleware do |chain|
    # This will join all "global" middleware with `MyWorkerSpecificMiddleware`
    # if you want to run only `MyWorkerSpecificMiddleware` for this worker
    # you can `chain.clear`
    # or to remove specific middleware for this worker you can `chain.remove OtherMiddleware`
    chain.add MyWorkerSpecificMiddleware
  end
end

Rejecting messages with a middleware

If you don't yield in a Middleware, no other middleware or worker will process it.

class RejectInvalidMessagesMiddleware
  def call(worker_instance, queue, sqs_msg, body)
    if valid?(sqs_msg)
      # will consume the message
      yield
    else
      # will not consume the message
      Shoryuken.logger.info "sqs_msg '#{sqs_msg.id}' is invalid and was rejected"
      sqs_msg.delete
    end
  end
end

Note: When batch is enabled, the sqs_msg and body arguments are arrays.