Class: Bogo::Retry

Inherits:
Object
  • Object
show all
Defined in:
lib/bogo/retry.rb

Overview

Perform action and retry until successful or abort

Direct Known Subclasses

Exponential, Flat, Linear

Defined Under Namespace

Classes: Exponential, Flat, Linear

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(args = {}, &block) ⇒ self

Create a new retry instance

Parameters:

  • args (Hash) (defaults to: {})

Options Hash (args):

  • :description (String) —

    action description

  • :ui (Bogo::Ui) —

    output failure/retry notifications

  • :max_attempts (Integer) —

    maximum number of retries



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# File 'lib/bogo/retry.rb', line 35

def initialize(args={}, &block)
  unless(block)
    raise ArgumentError,
      'Expecting block but no block was provided!'
  end
  args = args.to_smash
  @ui = args[:ui]
  @description = args.fetch(:description, 'Task')
  @max_attempts = args[:max_attempts]
  @action = block
  @attempts = 0
  @dead = false
  run! unless args[:auto_run] == false
end

Instance Attribute Details

#action ⇒ Proc (readonly)

Returns action to perform.

Returns:

  • (Proc) —

    action to perform



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# File 'lib/bogo/retry.rb', line 16

def action
  @action
end

#attempts ⇒ Integer (readonly)

Returns number of attempts.

Returns:

  • (Integer) —

    number of attempts



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# File 'lib/bogo/retry.rb', line 18

def attempts
  @attempts
end

#dead ⇒ TrueClass, FalseClass (readonly)

Returns retry is dead.

Returns:

  • (TrueClass, FalseClass) —

    retry is dead



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# File 'lib/bogo/retry.rb', line 20

def dead
  @dead
end

#description ⇒ String (readonly)

Returns description of action.

Returns:

  • (String) —

    description of action



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# File 'lib/bogo/retry.rb', line 22

def description
  @description
end

#max_attempts ⇒ Integer (readonly)

Returns maximum number of attempts.

Returns:

  • (Integer) —

    maximum number of attempts



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# File 'lib/bogo/retry.rb', line 24

def max_attempts
  @max_attempts
end

#ui ⇒ Bogo::Ui (readonly)

Returns UI to direct warnings.

Returns:

  • (Bogo::Ui) —

    UI to direct warnings



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# File 'lib/bogo/retry.rb', line 26

def ui
  @ui
end

Class Method Details

.build(type, *args) { ... } ⇒ Retry

Create a type of retry

Parameters:

  • type (String, Symbol) —

    name of retry type

  • args (Object) —

    instantiation arguments

Yields:

  • instantiation block

Returns:

  • (Retry) —

    specific subclass instance



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# File 'lib/bogo/retry.rb', line 10

def self.build(type, *args, &block)
  klass = self.const_get(Bogo::Utility.camel(type))
  klass.new(*args, &block)
end

Instance Method Details

#retries ⇒ Integer

Returns:

  • (Integer) 


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# File 'lib/bogo/retry.rb', line 90

def retries
  attempts > 0 ? attempts - 1 : 0
end

#run! {|exception| ... } ⇒ Object

Run action until success

Yields:

  • optional to allow custom exception check

Yield Parameters:

  • exception (Exception) —

    caught

Yield Returns:

  • (TrueClass, FalseClass) —

    if retry should be peformed

Returns:

  • (Object) —

    result of action



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# File 'lib/bogo/retry.rb', line 56

def run!
  if(dead)
    raise RuntimeError,
      "Action has already reached maximum allowed attempts (#{max_attempts})!"
  else
    begin
      log_attempt!
      action.call
    rescue => e
      if(block_given?)
        raise unless yield(e)
      end
      if(max_attempts.nil? || attempts < max_attempts)
        interval = wait_on_failure(e)
        if(ui)
          if(max_attempts)
            attempt_info = "[Attempt #{attempts}/#{max_attempts}]"
          end
          ui.warn "#{description} failed (#{e.class}: #{e}) - Retry in #{interval.to_i} seconds #{attempt_info}"
        end
        sleep(interval)
        retry
      else
        if(ui && max_attempts.to_i > 0)
          ui.error "#{description} failed (#{e.class}: #{e}) - Maximum number of attempts reached!"
        end
        @dead = true
        raise e
      end
    end
  end
end