A quick introduction to the Ruote workflow and BPM engine by John Mettraux, presented by myself at the third monthly Ruby on Beer meetup.

1. ruote - open source ruby workflow and bpm engine Developed by John Mettraux jmettraux.wordpress.com Presented by Kenneth Kalmer in 20 minutes opensourcery.co.za

3. Long running processes, long-lived process interpreter

4. Diverse participants

5. Complex rules & decisions

6. Implement clearly defined business processes

8. Selects the best deal for you

9. Handles application for you

10. You sign

11. You buy

12. You pay

14. :evaluation

15. :acquired

16. :accepted

17. :applied

19. When?

20. Rate?

21. Comparison?

22. Who?

23. Rule: Notify Client when 4 quotes are received aasm_state :pending_four_left aasm_state :pending_three_left aasm_state :pending_two_left aasm_state :pending_one_left aasm_state :pending_but_notified_client ... aasm_state :is_this_ridiculous_or_what?

24. Rule: Wait up to 7 days for quotes aasm_state :pending_four_remaining_timeout aasm_state :pending_three_remaining_timout aasm_state :pending_two_remaining_timout aasm_state :pending_one_remaining_timout … aasm_state :call_recruiter_for_new_dev!

26. Tempted to setup hundreds of states, with complex transitions

27. State machines help manage the results of real life processes, not the processes

28. Modified State Machine class Mortgage aasm_initial_state :pending aasm_state :pending aasm_state :quoted aasm_state :applied aasm_state :approved aasm_state :rejected end

32. Timeouts

33. Easy decision making

35. Conditional statements that facilitate branching and merging patterns

37. Can be automated code

38. Can be human interaction

39. Ruote provides plenty of participants out the box

40. Breeze to write new ones

41. First round: Participants class MortgageApplication < OpenWFE::ProcessDefinition sequence do institution_1 :activity => 'Mortgage Quote' institution_2 :activity => 'Mortgage Quote' institution_3 :activity => 'Mortgage Quote' institution_4 :activity => 'Mortgage Quote' institution_5 :activity => 'Mortgage Quote' institution_6 :activity => 'Mortgage Quote' institution_7 :activity => 'Mortgage Quote' end end

43. 14 days to complete if each institution takes 2 days on average

45. Send all requests in one go, and continue the process once we've received at least 4 quotes

46. Also, quote process may not take longer than 7 days to complete

47. Second round: Concurrency and Timeout class MortgageApplication < OpenWFE::ProcessDefinition sequence do timeout :after => '7d' do concurrence :count => 4 do institution_1 :activity => 'Mortgage Quote' institution_2 :activity => 'Mortgage Quote' institution_3 :activity => 'Mortgage Quote' institution_4 :activity => 'Mortgage Quote' institution_5 :activity => 'Mortgage Quote' institution_6 :activity => 'Mortgage Quote' institution_7 :activity => 'Mortgage Quote' e nd end end end

49. Process will take 7 days at most to complete

50. First 4 institutions stand the chance of earning new business

51. Mortgage is still “pending”

53. Can request quotes any number of times

54. But, wants to let the client know he's doing his best!

55. Third round: Bargain hard class MortgageApplication < OpenWFE::ProcessDefinition sequence do loop do concurrence :timeout => '7d', :count => 4 do institution_1 :activity => 'Mortgage Quote' # ... e nd joe :activity => 'Review quotes' _break :if => “${f:joe_happy}” email :activity => “Getting new quotes”, :to => “${f:client.email}” end end end

57. Client notified everytime the quote request process starts all over again

58. First glimpse of workitems

59. Mortgage is still “pending”

61. They're JSON friendly Ruby hashes

62. Participants can modify workitems

63. Processes can be launched with an initial payload, client details in this case, which is accessed through the workitems

64. Workitem attributes accessed in process definitions through the “dollar notation”

65. Quote found, action the client class MortgageApplication < OpenWFE::ProcessDefinition sequence do loop do # ... end secretary :activity => “Send client application forms” end end

66. Application received, apply at institution class MortgageApplication < OpenWFE::ProcessDefinition sequence do # ... secretary :activity => “Send client application forms” participant :ref => “${f:selected_institution}”, :activity => “Apply for mortgage” end end

68. Another human participant

69. Mortgage now in “applied” state

71. Might attempt to restart the entire process

72. Joe has last say class MortgageApplication < OpenWFE::ProcessDefinition sequence do # ... participant :ref => “${f:selected_institution}”, :activity => “Apply for mortgage” joe :activity => “Review application results” end end

74. Mortgage will stay in “applied” state, or move to “approved”/”rejected” states

75. Process ends

78. Harass institutions that don't respond within 2 days of process timeout

79. Joe improves his handicap

81. Ruote handles business logic, AASM the state

82. AASM becomes skinny, ruote stays declarative

84. Jabber messages

85. Atom feed entries

87. Replay failed steps

88. Redo steps based on conditions

89. Jump to any point in the workflow using cursors

91. Edit process definitions on the fly

94. Added support for daemonizing ruote-rest

95. In talks on refactoring ruote-rest to become preferred “Rails-friendly” implementation of ruote

97. Expressions are “steps in the workflow”

98. Participants perform explicit function during workflow

99. Workitems used as “internal messaging” mechanism between expressions/participants

100. The best complement to any state machine implementation

101. Simplifies complex business process implementations

102. You have full control over the entire process

103. Thank You opensourcery.co.za @kennethkalmer openwferu.rubyforge.org #ruote on Freenode groups.google.com/group/openwferu-users @jmettraux