Class: Dynflow::ExecutionPlan

Inherits:
Serializable show all
Includes:
Algebrick::TypeCheck, Stateful
Defined in:
lib/dynflow/execution_plan.rb,
lib/dynflow/execution_plan/hooks.rb

Overview

rubocop:disable Metrics/ClassLength TODO extract planning logic to an extra class ExecutionPlanner

Defined Under Namespace

Modules: Hooks, Steps Classes: DependencyGraph, InvalidPlan, OutputReference

Constant Summary

Constants inherited from Serializable

Serializable::LEGACY_TIME_FORMAT, Serializable::TIME_FORMAT

Instance Attribute Summary collapse

Attributes included from Stateful

#state

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Stateful

included, #set_state, #state_transitions, #states

Methods inherited from Serializable

constantize, from_hash

Constructor Details

#initialize(world, id = nil, label = nil, state = :pending, root_plan_step = nil, run_flow = Flows::Concurrence.new([]), finalize_flow = Flows::Sequence.new([]), steps = {}, started_at = nil, ended_at = nil, execution_time = nil, real_time = 0.0, execution_history = ExecutionHistory.new) ⇒ ExecutionPlan

all params with default values are part of private api



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# File 'lib/dynflow/execution_plan.rb', line 72

def initialize(world,
               id                = nil,
               label             = nil,
               state             = :pending,
               root_plan_step    = nil,
               run_flow          = Flows::Concurrence.new([]),
               finalize_flow     = Flows::Sequence.new([]),
               steps             = {},
               started_at        = nil,
               ended_at          = nil,
               execution_time    = nil,
               real_time         = 0.0,
               execution_history = ExecutionHistory.new)
  id ||= SecureRandom.uuid
  @id = Type! id, String
  @world = Type! world, World
  @label = Type! label, String, NilClass
  self.state         = state
  @run_flow          = Type! run_flow, Flows::Abstract
  @finalize_flow     = Type! finalize_flow, Flows::Abstract
  @root_plan_step    = root_plan_step
  @started_at        = Type! started_at, Time, NilClass
  @ended_at          = Type! ended_at, Time, NilClass
  @execution_time    = Type! execution_time, Numeric, NilClass
  @real_time         = Type! real_time, Numeric
  @execution_history = Type! execution_history, ExecutionHistory

  steps.all? do |k, v|
    Type! k, Integer
    Type! v, Steps::Abstract
  end
  @steps = steps
end

Instance Attribute Details

#ended_at ⇒ Object (readonly)

Returns the value of attribute ended_at.



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# File 'lib/dynflow/execution_plan.rb', line 47

def ended_at
  @ended_at
end

#execution_history ⇒ Object (readonly)

Returns the value of attribute execution_history.



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# File 'lib/dynflow/execution_plan.rb', line 47

def execution_history
  @execution_history
end

#execution_time ⇒ Object (readonly)

Returns the value of attribute execution_time.



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# File 'lib/dynflow/execution_plan.rb', line 47

def execution_time
  @execution_time
end

#finalize_flow ⇒ Object (readonly)

Returns the value of attribute finalize_flow.



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# File 'lib/dynflow/execution_plan.rb', line 47

def finalize_flow
  @finalize_flow
end

#id ⇒ Object (readonly)

Returns the value of attribute id.



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# File 'lib/dynflow/execution_plan.rb', line 47

def id
  @id
end

#label ⇒ Object (readonly)

Returns the value of attribute label.



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# File 'lib/dynflow/execution_plan.rb', line 47

def label
  @label
end

#real_time ⇒ Object (readonly)

Returns the value of attribute real_time.



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# File 'lib/dynflow/execution_plan.rb', line 47

def real_time
  @real_time
end

#root_plan_step ⇒ Object (readonly)

Returns the value of attribute root_plan_step.



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# File 'lib/dynflow/execution_plan.rb', line 47

def root_plan_step
  @root_plan_step
end

#run_flow ⇒ Object (readonly)

Returns the value of attribute run_flow.



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# File 'lib/dynflow/execution_plan.rb', line 47

def run_flow
  @run_flow
end

#started_at ⇒ Object (readonly)

Returns the value of attribute started_at.



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# File 'lib/dynflow/execution_plan.rb', line 47

def started_at
  @started_at
end

#steps ⇒ Object (readonly)

Returns the value of attribute steps.



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# File 'lib/dynflow/execution_plan.rb', line 47

def steps
  @steps
end

#world ⇒ Object (readonly)

Returns the value of attribute world.



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# File 'lib/dynflow/execution_plan.rb', line 47

def world
  @world
end

Class Method Details

.load_flow(flow_hash) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 426

def self.load_flow(flow_hash)
  if flow_hash.is_a? Hash
    Flows::Abstract.from_hash(flow_hash)
  else
    Flows::Abstract.decode(flow_hash)
  end
end

.new_from_hash(hash, world) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 455

def self.new_from_hash(hash, world)
  check_class_matching hash
  execution_plan_id = hash[:id]
  steps             = steps_from_hash(hash[:step_ids], execution_plan_id, world)
  self.new(world,
    execution_plan_id,
    hash[:label],
    hash[:state],
    steps[hash[:root_plan_step_id]],
    load_flow(hash[:run_flow]),
    load_flow(hash[:finalize_flow]),
    steps,
    string_to_time(hash[:started_at]),
    string_to_time(hash[:ended_at]),
    hash[:execution_time].to_f,
    hash[:real_time].to_f,
    ExecutionHistory.new_from_hash(hash[:execution_history]))
rescue => plan_exception
  begin
    world.logger.error("Could not load execution plan #{execution_plan_id}")
    world.logger.error(plan_exception)
    InvalidPlan.new(plan_exception, execution_plan_id,
      hash[:label],
      hash[:state],
      string_to_time(hash[:started_at]),
      string_to_time(hash[:ended_at]),
      hash[:execution_time].to_f,
      hash[:real_time].to_f,
      ExecutionHistory.new_from_hash(hash[:execution_history]))
  rescue => invalid_plan_exception
    world.logger.error("Could not even load a fallback execution plan for #{execution_plan_id}")
    world.logger.error(invalid_plan_exception)
    InvalidPlan.new(invalid_plan_exception, execution_plan_id,
      hash[:label],
      hash[:state])
  end
end

.results ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 57

def self.results
  @results ||= [:pending, :success, :warning, :error, :cancelled]
end

.state_transitions ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 61

def self.state_transitions
  @state_transitions ||= { pending:  [:stopped, :scheduled, :planning],
                           scheduled: [:planning, :stopped],
                           planning: [:planned, :stopped],
                           planned:  [:running, :stopped],
                           running:  [:paused, :stopped],
                           paused:   [:running, :stopped],
                           stopped:  [] }
end

.states ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 51

def self.states
  @states ||= [:pending, :scheduled, :planning, :planned, :running, :paused, :stopped]
end

Instance Method Details

#actions ⇒ Array<Action>

Returns actions in Present phase.

Returns:

  • (Array<Action>) —

    actions in Present phase



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# File 'lib/dynflow/execution_plan.rb', line 517

def actions
  @actions ||= begin
    [entry_action] + entry_action.all_planned_actions
  end
end

#add_finalize_step(action) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 419

def add_finalize_step(action)
  add_step(Steps::FinalizeStep, action.class, action.id).tap do |step|
    step.update_from_action(action)
    finalize_flow << Flows::Atom.new(step.id)
  end
end

#add_plan_step(action_class, caller_action = nil) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 401

def add_plan_step(action_class, caller_action = nil)
  add_step(Steps::PlanStep, action_class, generate_action_id).tap do |step|
    # TODO: to be removed and preferred by the caller_action
    if caller_action && caller_action.execution_plan_id == self.id
      @steps[caller_action.plan_step_id].children << step.id
    end
    step.initialize_action(caller_action)
  end
end

#add_run_step(action) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 411

def add_run_step(action)
  add_step(Steps::RunStep, action.class, action.id).tap do |step|
    step.update_from_action(action)
    @dependency_graph.add_dependencies(step, action)
    current_run_flow.add_and_resolve(@dependency_graph, Flows::Atom.new(step.id))
  end
end

#add_scheduling_step(action_class, caller_action = nil) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 395

def add_scheduling_step(action_class, caller_action = nil)
  add_step(Steps::PlanStep, action_class, generate_action_id, :scheduling).tap do |step|
    step.initialize_action(caller_action)
  end
end

#caller_execution_plan_id ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 523

def caller_execution_plan_id
  entry_action.caller_execution_plan_id
end

#cancel(force = false) ⇒ Object

sends the cancel event to all currently running and cancellable steps. if the plan is just scheduled, it cancels it (and returns an one-item array with the future value of the cancel result)



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# File 'lib/dynflow/execution_plan.rb', line 311

def cancel(force = false)
  if state == :scheduled
    [Concurrent::Promises.resolvable_future.tap { |f| f.fulfill delay_record.cancel }]
  else
    event = force ? ::Dynflow::Action::Cancellable::Abort : ::Dynflow::Action::Cancellable::Cancel
    steps_to_cancel.map do |step|
      world.event(id, step.id, event)
    end
  end
end

#cancellable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dynflow/execution_plan.rb', line 322

def cancellable?
  return true if state == :scheduled
  return false unless state == :running
  steps_to_cancel.any?
end

#compute_execution_time ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 493

def compute_execution_time
  self.steps.values.reduce(0) do |execution_time, step|
    execution_time + (step.execution_time || 0)
  end
end

#current_run_flow ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 371

def current_run_flow
  @run_flow_stack.last
end

#delay(caller_action, action_class, delay_options, *args) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 256

def delay(caller_action, action_class, delay_options, *args)
  save
  @root_plan_step = add_scheduling_step(action_class, caller_action)
  run_hooks(:pending)
  serializer = root_plan_step.delay(delay_options, args)
  delayed_plan = DelayedPlan.new(@world,
    id,
    delay_options[:start_at],
    delay_options.fetch(:start_before, nil),
    serializer,
    delay_options[:frozen] || false)
  persistence.save_delayed_plan(delayed_plan)
ensure
  update_state(error? ? :stopped : :scheduled)
end

#delay_record ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 272

def delay_record
  @delay_record ||= persistence.load_delayed_plan(id)
end

#entry_action ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 512

def entry_action
  @entry_action ||= root_plan_step.action(self)
end

#error? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dynflow/execution_plan.rb', line 183

def error?
  result == :error
end

#error_in_plan? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dynflow/execution_plan.rb', line 191

def error_in_plan?
  steps_in_state(:error).any? { |step| step.is_a? Steps::PlanStep }
end

#errors ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 195

def errors
  steps.values.map(&:error).compact
end

#failed_steps ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 238

def failed_steps
  steps_in_state(:error)
end

#failure? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dynflow/execution_plan.rb', line 187

def failure?
  [:error, :warning, :cancelled].include?(result)
end

#finalize_steps ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 234

def finalize_steps
  steps_of_type(Dynflow::ExecutionPlan::Steps::FinalizeStep)
end

#generate_action_id ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 246

def generate_action_id
  @last_action_id ||= 0
  @last_action_id += 1
end

#generate_step_id ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 251

def generate_step_id
  @last_step_id ||= 0
  @last_step_id += 1
end

#logger ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 110

def logger
  @world.logger
end

#plan(*args) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 287

def plan(*args)
  update_state(:planning)
  world.middleware.execute(:plan_phase, root_plan_step.action_class, self) do
    with_planning_scope do
      root_action = root_plan_step.execute(self, nil, false, *args)
      @label = root_action.label

      if @dependency_graph.unresolved?
        raise "Some dependencies were not resolved: #{@dependency_graph.inspect}"
      end
    end
  end

  if @run_flow.size == 1
    @run_flow = @run_flow.sub_flows.first
  end

  steps.values.each(&:save)
  update_state(error? ? :stopped : :planned)
end

#plan_steps ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 226

def plan_steps
  steps_of_type(Dynflow::ExecutionPlan::Steps::PlanStep)
end

#prepare(action_class, options = {}) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 276

def prepare(action_class, options = {})
  options = options.dup
  caller_action = Type! options.delete(:caller_action), Dynflow::Action, NilClass
  raise "Unexpected options #{options.keys.inspect}" unless options.empty?
  save
  @root_plan_step = add_plan_step(action_class, caller_action)
  step = @root_plan_step.save
  run_hooks(:pending)
  step
end

#prepare_for_rescue ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 212

def prepare_for_rescue
  case rescue_strategy
  when Action::Rescue::Pause
    :paused
  when Action::Rescue::Fail
    :stopped
  when Action::Rescue::Skip
    failed_steps.each { |step| self.skip(step) }
    :running
  else
    :paused
  end
end

#progress ⇒ 0..1

info

Returns:

  • (0..1) —

    the percentage of the progress. See Action::Progress for more



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# File 'lib/dynflow/execution_plan.rb', line 501

def progress
  return 0 if [:pending, :planning, :scheduled].include?(state)
  flow_step_ids         = run_flow.all_step_ids + finalize_flow.all_step_ids
  plan_done, plan_total = flow_step_ids.reduce([0.0, 0]) do |(done, total), step_id|
    step = self.steps[step_id]
    [done + (step.progress_done * step.progress_weight),
     total + step.progress_weight]
  end
  plan_total > 0 ? (plan_done / plan_total) : 1
end

#rescue_strategy ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 199

def rescue_strategy
  rescue_strategy = entry_action.rescue_strategy || Action::Rescue::Skip
  Type! rescue_strategy, Action::Rescue::Strategy
end

#result ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 168

def result
  all_steps = steps.values
  if all_steps.any? { |step| step.state == :cancelled }
    return :cancelled
  elsif all_steps.any? { |step| step.state == :error }
    return :error
  elsif all_steps.any? { |step| [:skipping, :skipped].include?(step.state) }
    return :warning
  elsif all_steps.all? { |step| step.state == :success }
    return :success
  else
    return :pending
  end
end

#run_hooks(state) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 153

def run_hooks(state)
  records = persistence.load_actions_attributes(@id, [:id, :class]).select do |action|
    Utils.constantize(action[:class])
         .execution_plan_hooks
         .on(state).any?
  end
  action_ids = records.compact.map { |record| record[:id] }
  return if action_ids.empty?
  persistence.load_actions(self, action_ids).each do |action|
    world.middleware.execute(:hook, action, self) do
      action.class.execution_plan_hooks.run(self, action, state)
    end
  end
end

#run_steps ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 230

def run_steps
  steps_of_type(Dynflow::ExecutionPlan::Steps::RunStep)
end

#save ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 451

def save
  persistence.save_execution_plan(self)
end

#skip(step) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 334

def skip(step)
  steps_to_skip = steps_to_skip(step).each(&:mark_to_skip)
  self.save
  return steps_to_skip
end

#steps_in_state(*states) ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 242

def steps_in_state(*states)
  self.steps.values.find_all { |step| states.include?(step.state) }
end

#steps_of_type(type) ⇒ 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. 



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# File 'lib/dynflow/execution_plan.rb', line 367

def steps_of_type(type)
  steps.values.find_all { |step| step.is_a?(type) }
end

#steps_to_cancel ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 328

def steps_to_cancel
  steps_in_state(:running, :suspended).find_all do |step|
    step.action(self).is_a?(::Dynflow::Action::Cancellable)
  end
end

#steps_to_skip(step) ⇒ Array<Steps::Abstract>

All the steps that need to get skipped when wanting to skip the step includes the step itself, all steps dependent on it (even transitively) FIND maybe move to persistence to let adapter to do it effectively?

Returns:



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# File 'lib/dynflow/execution_plan.rb', line 344

def steps_to_skip(step)
  dependent_steps = steps.values.find_all do |s|
    next if s.is_a? Steps::PlanStep
    action = persistence.load_action(s)
    action.required_step_ids.include?(step.id)
  end

  steps_to_skip = dependent_steps.map do |dependent_step|
    steps_to_skip(dependent_step)
  end.flatten

  steps_to_skip << step

  if step.is_a? Steps::RunStep
    finalize_step_id = persistence.load_action(step).finalize_step_id
    steps_to_skip << steps[finalize_step_id] if finalize_step_id
  end

  return steps_to_skip.uniq
end

#sub_plans ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 204

def sub_plans
  persistence.find_execution_plans(filters: { 'caller_execution_plan_id' => self.id })
end

#sub_plans_count ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 208

def sub_plans_count
  persistence.find_execution_plan_counts(filters: { 'caller_execution_plan_id' => self.id })
end

#switch_flow(new_flow, &block) ⇒ 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.

Switches the flow type (Sequence, Concurrence) to be used within the block.



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# File 'lib/dynflow/execution_plan.rb', line 387

def switch_flow(new_flow, &block)
  @run_flow_stack << new_flow
  return block.call
ensure
  @run_flow_stack.pop
  current_run_flow.add_and_resolve(@dependency_graph, new_flow) if current_run_flow
end

#to_hash ⇒ Object 



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# File 'lib/dynflow/execution_plan.rb', line 434

def to_hash
  recursive_to_hash id:                id,
                    class:             self.class.to_s,
                    label:             label,
                    state:             state,
                    result:            result,
                    root_plan_step_id: root_plan_step && root_plan_step.id,
                    run_flow:          run_flow.encode,
                    finalize_flow:     finalize_flow.encode,
                    step_ids:          steps.map { |id, _| id },
                    started_at:        time_to_str(started_at),
                    ended_at:          time_to_str(ended_at),
                    execution_time:    execution_time,
                    real_time:         real_time,
                    execution_history: execution_history.to_hash
end

#update_state(state, history_notice: :auto) ⇒ Object

Parameters:

  • state (Symbol) —

    representing the new state

  • history_notice (Symbol|string|false) (defaults to: :auto) —

    should a note to execution_history be added as well? Possible values:

    - :auto (default) - the history notice will be added based on the new state
- string - custom history notice is added
- false - don't add any notice



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# File 'lib/dynflow/execution_plan.rb', line 120

def update_state(state, history_notice: :auto)
  hooks_to_run = [state]
  original = self.state
  case self.state = state
  when :planning
    @started_at = Time.now.utc
  when :stopped
    @ended_at       = Time.now.utc
    @real_time      = @ended_at - @started_at unless @started_at.nil?
    @execution_time = compute_execution_time
    key = failure? ? :failure : :success
    Dynflow::Telemetry.with_instance do |t|
      t.increment_counter(:dynflow_finished_execution_plans, 1,
        telemetry_common_options.merge(:result => key.to_s))
    end
    hooks_to_run << key
    world.persistence.delete_delayed_plans(:execution_plan_uuid => id) if delay_record && original == :scheduled
    unlock_all_singleton_locks!
    unlock_execution_inhibition_lock!
  when :paused
    unlock_all_singleton_locks!
  else
    # ignore
  end
  logger.debug format('%13s %s    %9s >> %9s',
    'ExecutionPlan', id, original, state)
  add_history_notice(history_notice)
  self.save
  toggle_telemetry_state original == :pending ? nil : original.to_s,
    self.state == :stopped ? nil : self.state.to_s
  hooks_to_run.each { |kind| run_hooks kind }
end

#valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dynflow/execution_plan.rb', line 106

def valid?
  true
end

#with_planning_scope(&block) ⇒ 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. 



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# File 'lib/dynflow/execution_plan.rb', line 376

def with_planning_scope(&block)
  @run_flow_stack   = []
  @dependency_graph = DependencyGraph.new
  switch_flow(run_flow, &block)
ensure
  @run_flow_stack   = nil
  @dependency_graph = nil
end