Class: AWS::Flow::WorkflowWorker

Inherits:
GenericWorker show all
Defined in:
lib/aws/decider/worker.rb

Overview

This worker class is intended for use by the workflow implementation. It is configured with a task list and a workflow implementation. The worker class polls for decision tasks in the specified task list. When a decision task is received, it creates an instance of the workflow implementation and calls the @ execute() decorated method to process the task.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from GenericWorker

#camel_case_to_snake_case, #resolve_default_task_list

Constructor Details

#initialize(service, domain, task_list, *args, &block) ⇒ WorkflowWorker

Creates a new WorkflowWorker instance.

Parameters:

  • service —

    The service used with this workflow worker.

  • domain (String) —

    The Amazon SWF domain to operate on.

  • task_list (Array) —

    The default task list to put all of the decision requests.

  • args —

    The decisions to use.



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# File 'lib/aws/decider/worker.rb', line 130

def initialize(service, domain, task_list, *args, &block)
  @workflow_definition_map = {}
  @workflow_type_options = []
  @options = Utilities::interpret_block_for_options(WorkerOptions, block)

  @logger = @options.logger if @options
  @logger ||= Utilities::LogFactory.make_logger(self)
  @options.logger ||= @logger if @options

  super(service, domain, task_list, *args)
end

Instance Attribute Details

#workflow_type ⇒ Object

The workflow type for this workflow worker.



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# File 'lib/aws/decider/worker.rb', line 114

def workflow_type
  @workflow_type
end

Instance Method Details

#add_implementation(workflow_class) ⇒ Object 



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# File 'lib/aws/decider/worker.rb', line 146

def add_implementation(workflow_class)
  add_workflow_implementation(workflow_class)
end

#add_workflow_implementation(workflow_class) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Called by #add_implementation.



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# File 'lib/aws/decider/worker.rb', line 152

def add_workflow_implementation(workflow_class)
  workflow_class.workflows.delete_if do |workflow_type|
    workflow_type.version.nil? || workflow_type.name.nil?
  end
  workflow_class.workflows.each do |workflow_type|
    options = workflow_type.options
    execution_method = options.execution_method
    version = workflow_type.version
    registration_options = options.get_registration_options
    implementation_options = nil
    get_state_method = workflow_class.get_state_method
    signals = workflow_class.signals

    @workflow_definition_map[workflow_type] = WorkflowDefinitionFactory.new(
      workflow_class,
      workflow_type,
      registration_options,
      options,
      execution_method,
      signals,
      get_state_method
    )
    # TODO should probably do something like
    # GenericWorkflowWorker#registerWorkflowTypes
    workflow_hash = options.get_options(
      [
        :default_task_start_to_close_timeout,
        :default_execution_start_to_close_timeout,
        :default_child_policy
      ], {
        :domain => @domain.name,
        :name => workflow_type.name,
        :version => version
      }
    )

    if options.default_task_list
      workflow_hash.merge!(
        :default_task_list => {:name => resolve_default_task_list(options.default_task_list)}
      )
    end
    @workflow_type_options << workflow_hash
  end
end

#register ⇒ Object

Registers this workflow with Amazon SWF.



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# File 'lib/aws/decider/worker.rb', line 199

def register
  @workflow_type_options.delete_if {|workflow_type_options| workflow_type_options[:version].nil?}
  @workflow_type_options.each do |workflow_type_options|
    begin
      @service.register_workflow_type(workflow_type_options)
    rescue AWS::SimpleWorkflow::Errors::TypeAlreadyExistsFault => e
      @logger.warn "#{e.class} while trying to register workflow #{e.message} with options #{workflow_type_options}"
      # Purposefully eaten up, the alternative is to check first, and who
      # wants to do two trips when one will do?
    end
  end
end

#run_once(should_register = false, poller = nil) ⇒ Object

Starts the workflow and runs it once, with an optional AWS::Flow::WorkflowTaskPoller.

Parameters:

  • poller (defaults to: nil) —

    An optional AWS::Flow::WorkflowTaskPoller to use.

  • should_register (true, false) (defaults to: false) —

    Indicates whether the workflow needs to be registered with Amazon SWF first. If #register was already called for this workflow worker, specify ‘false`.



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# File 'lib/aws/decider/worker.rb', line 251

def run_once(should_register = false, poller = nil)
  register if should_register

  poller = WorkflowTaskPoller.new(
    @service,
    @domain,
    DecisionTaskHandler.new(@workflow_definition_map, @options),
    @task_list,
    @options
  ) if poller.nil?

  Kernel.exit if @shutting_down
  poller.poll_and_process_single_task
end

#set_workflow_implementation_types(workflow_implementation_types) ⇒ Object 



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# File 'lib/aws/decider/worker.rb', line 142

def set_workflow_implementation_types(workflow_implementation_types)
  workflow_implementation_types.each {|type| add_workflow_implementation(type)}
end

#start(should_register = true) ⇒ Object

Starts the workflow with a AWS::Flow::WorkflowTaskPoller.

Parameters:

  • should_register (true, false) (defaults to: true) —

    Indicates whether the workflow needs to be registered with Amazon SWF first. If #register was already called for this workflow worker, specify ‘false`.



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# File 'lib/aws/decider/worker.rb', line 220

def start(should_register = true)
  # TODO check to make sure that the correct properties are set
  # TODO Register the domain if not already registered
  # TODO register types to poll
  # TODO Set up throttler
  # TODO Set up a timeout on the throttler correctly,
  # TODO Make this a generic poller, go to the right kind correctly

  poller = WorkflowTaskPoller.new(
    @service,
    @domain,
    DecisionTaskHandler.new(@workflow_definition_map, @options),
    @task_list,
    @options
  )

  register if should_register
  @logger.debug "Starting an infinite loop to poll and process workflow tasks."
  loop do
    run_once(false, poller)
  end
end