Module: Legion::Gaia::Workflow

Defined in:
lib/legion/gaia/workflow.rb,
lib/legion/gaia/workflow/errors.rb,
lib/legion/gaia/workflow/instance.rb,
lib/legion/gaia/workflow/checkpoint.rb,
lib/legion/gaia/workflow/definition.rb

Overview

Generic state machine DSL for workflow orchestration.

Provides a ‘workflow` class method that defines a state machine on any Ruby class or module, plus `create_workflow` for instantiation.

Quick example

class DocProcessor
  include Legion::Gaia::Workflow

  workflow :document_processing do |w|
    w.state :received, initial: true
    w.state :parsing
    w.state :enriching
    w.state :indexed, terminal: true
    w.state :failed,  terminal: true

    w.transition :received,  to: :parsing
    w.transition :parsing,   to: :enriching, guard: ->(ctx) { ctx[:parse_ok] }
    w.transition :parsing,   to: :failed
    w.transition :enriching, to: :indexed
    w.transition :enriching, to: :failed

    w.checkpoint :enriching, name: :quality_check,
                 condition: ->(ctx) { ctx[:score].to_f >= 0.8 }

    w.on_enter(:indexed) { |inst| puts "Indexed! id=#{inst.id}" }
    w.on_enter(:failed)  { |inst| puts "Failed!  id=#{inst.id}" }
  end
end

inst = DocProcessor.create_workflow(metadata: { doc_id: 42 })
inst.transition!(:parsing)
inst.transition!(:enriching, parse_ok: true)
inst.transition!(:indexed, score: 0.9)

Standalone (no include)

You can also use the DSL directly:

defn = Legion::Gaia::Workflow.define(:my_pipeline) do |w|
  w.state :start, initial: true
  w.state :finish, terminal: true
  w.transition :start, to: :finish
end
inst = Legion::Gaia::Workflow::Instance.new(definition: defn)
inst.transition!(:finish)

Defined Under Namespace

Modules: ClassMethods Classes: Checkpoint, CheckpointBlocked, Definition, Error, GuardRejected, Instance, InvalidTransition, NotInitialized, UnknownState

Class Method Summary collapse

Class Method Details

.define(name) {|definition| ... } ⇒ Definition

Build a Definition without including the module into a class.

Parameters:

  • name (Symbol, String)

Yields:

  • (definition) —

    receives the Definition object for DSL calls

Returns:



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# File 'lib/legion/gaia/workflow.rb', line 112

def self.define(name, &block)
  defn = Definition.new(name.to_sym)
  block&.call(defn)
  defn
end

.included(base) ⇒ Object

—————————————————————— class methods



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# File 'lib/legion/gaia/workflow.rb', line 60

def self.included(base)
  base.extend(ClassMethods)
end