Module: Ncio::Support::RetryAction

Defined in:
lib/ncio/support/retry_action.rb

Overview

Provide a method to retry arbitrary code blocks with the ability to rescue certain exceptions and retry rather than failing hard on the exception.

Copied from: https://github.com/puppetlabs/puppetlabs-cloud_provisioner/blob/f6cbac3/lib/puppet/cloudpack/utils.rb

Defined Under Namespace

Classes: RetryException

Class Method Summary collapse

Class Method Details

.retry_action(params = { retry_exceptions: nil, timeout: nil, log: nil }) ⇒ Object

Retry an action, catching exceptions and retrying if the exception has been specified.

rubocop:disable Metrics/PerceivedComplexity, Metrics/MethodLength rubocop:disable Metrics/CyclomaticComplexity, Metrics/AbcSize

Raises:



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# File 'lib/ncio/support/retry_action.rb', line 28

def self.retry_action(params = { retry_exceptions: nil, timeout: nil, log: nil })
  # Retry actions for a specified amount of time. This method will allow
  # the final retry to complete even if that extends beyond the timeout
  # period.
  raise RetryException::NoBlockGiven unless block_given?

  raise RetryException::NoTimeoutGiven if params[:timeout].nil?
  params[:retry_exceptions] ||= []

  # Assumes reset_logging! has been called.  This happens in the Ncio::App
  # initialization.
  log = params[:log] || Ncio::Support.log

  start = Time.now
  failures = 0

  # rubocop:disable Lint/RescueException
  begin
    yield

  rescue Exception => e
    # If we were giving exceptions to catch,
    # catch the exceptions we care about and retry.
    # All others fail hard

    raise RetryException::Timeout if timedout?(start, params[:timeout])

    retry_exceptions = params[:retry_exceptions]

    unless retry_exceptions.empty?
      if retry_exceptions.include?(e.class)
        log.warn("Retrying: #{e.class}: #{e}")
      else
        # If the exceptions is not in the list of retry_exceptions
        # re-raise.
        raise e
      end
    end
    # rubocop:enable Lint/RescueException

    failures += 1
    # Increase the amount of time that we sleep after every
    # failed retry attempt.
    sleep(((2**failures) - 1) * 0.1)

    retry
  end
  # rubocop:enable Metrics/PerceivedComplexity, Metrics/MethodLength
end

.timedout?(start, timeout) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ncio/support/retry_action.rb', line 17

def self.timedout?(start, timeout)
  return true if timeout.nil?
  (Time.now - start) >= timeout
end