Class: Ruote::Exp::ReserveExpression

Inherits:
FlowExpression show all
Defined in:
lib/ruote/exp/fe_reserve.rb

Overview

Prevents two process branches from executing at the same time.

pdef = Ruote.process_definition :name => 'test' do
  concurrence do
    reserve :mutex => 'a' do
      alpha
    end
    reserve 'a' do
      alpha
    end
  end
end

(Nice and tiny example, turns a concurrence into a sequence…)

Constant Summary

Constants inherited from FlowExpression

FlowExpression::COMMON_ATT_KEYS

Instance Attribute Summary

Attributes inherited from FlowExpression

#context, #error, #h

Instance Method Summary collapse

Methods inherited from FlowExpression

#ancestor?, #att, #attribute, #attribute_text, #attributes, #compile_atts, #compile_variables, do_action, #do_apply, #do_cancel, #do_fail, #do_pause, #do_persist, #do_reply, #do_resume, #do_unpersist, #expand_atts, #fei, fetch, from_h, #handle_on_error, #has_attribute, #initial_persist, #initialize, #iterative_var_lookup, #launch_sub, #lookup_on_error, #lookup_val, #lookup_val_prefix, #lookup_variable, #name, names, #parent, #parent_id, #persist_or_raise, #reply_to_parent, #set_variable, #to_h, #tree, #tree_children, #try_persist, #try_unpersist, #unpersist_or_raise, #unset_variable, #update_tree, #variables

Methods included from WithMeta

#class_def, included

Methods included from WithH

included

Constructor Details

This class inherits a constructor from Ruote::Exp::FlowExpression

Instance Method Details

#apply ⇒ Object

Raises:

  • (ArgumentError) 


48
49
50
51
52
53
54
55
56
57
58
59
60
 
# File 'lib/ruote/exp/fe_reserve.rb', line 48

def apply

  return reply_to_parent(h.applied_workitem) if tree_children.empty?

  h.mutex_name = attribute(:mutex) || attribute_text
  h.mutex_name = 'reserve' if h.mutex_name.strip == ''

  raise(
    ArgumentError.new("can't bind reserve mutex at engine level")
  ) if h.mutex_name.match(/^\/\//)

  set_mutex
end

#cancel(flavour) ⇒ Object 



69
70
71
72
73
74
 
# File 'lib/ruote/exp/fe_reserve.rb', line 69

def cancel(flavour)

  super

  release_mutex
end

#enter ⇒ Object 



76
77
78
79
 
# File 'lib/ruote/exp/fe_reserve.rb', line 76

def enter

  apply_child(0, h.applied_workitem)
end

#reply(workitem) ⇒ Object 



62
63
64
65
66
67
 
# File 'lib/ruote/exp/fe_reserve.rb', line 62

def reply(workitem)

  release_mutex

  reply_to_parent(workitem)
end