Towards ruote 2.0 (2009)

An old deck about ruote, still interesting

Transcript

1. ruote 2.0 2009/10/07
2. warning : these slides pre-suppose you have some familiarity with ruote (0.9.x)
3. ‣ recap : ruote ‣ is a ruby workflow engine ‣ ruby makes it easy to tinker and try ‣ workflows should be easy to tinker and try ‣ with some discipline, you might even end up doing BPM with it
4. agenda
5. agenda
7. ruote 2.0 engine
8. ‣ ruote engine : historically ‣ middleware/backend-ish ‣ not for your big front web 2.0 app ‣ cheap workflow engine ‣ 1 engine per business unit
9. ‣ ruote engine : core requirements ‣ has to run multiple processes ‣ with multiple branches ‣ and/or subprocesses ‣ can be stopped / restarted (if running with persistent storage) ‣ can run multiple versions of any process ‣ has to allow in-flight modifications to processes
10. ‣ ruote 2.0 engine ‣ multi ruby process resilient :( ‣ complete rewrite with a cleaner interface
11. ‣ multi-process ‣ the average user wants to put ruote in his rails app ‣ the rails app is in a ‘multi-process’ ruby web server ‣ ruote 0.9 is in trouble...
12. ‣ multi-process resilience ‣ ruote 2.0 knows it could run in a multi-process env ‣ it has defense mechanisms things like ‘tickets’ and ‘locks’ ‣ they have a cost :-( ‣ suggestions ‣ avoid mp envs for ruote (the engine is idle most of the time) ‣ run ruote as a webservice in a 1p env ‣ (ruote in 1p can use “caching” and be faster)
13. ‣ our favourite env these days ‣ ruote-{kit|http} workflow as an http service ‣ ruote-amqp ‣ remote participants as amqp (daemons) http://github.com/kennethkalmer/daemon-kit ‣ load on ruote itself is low
14. ‣ anyway... ‣ 1 engine that scale for everything ? ‣ why not 1 engine per domain / unit ? ‣ why not a separation between tactical and technical engines ? ‣ why not engines that talk to each other ? ‣ scale the business or scale the tools ?
15. ‣ engine workqueue ‣ where each operation is performed ‣ only 1 op at a time ‣ by default, uses Thread/Queue ‣ uses EventMachine if present ‣ future work : ‣ fibers ? ‣ it’s an implementation away ‣ anyway, engine is idle most of the time (usually waiting for those slow humans)
16. cleaner interface
17. cleaner interface
19. ruote 2.0 process definitions
20. ‣ AST is JSON friendly ‣ attributes common to all expressions ‣ :if / :unless ‣ :timeout, :on_timeout ‣ :on_cancel / :on_error ‣ :forget ‣ directed commands ‣ break :ref => ‘tag’ ‣ jump :to => ‘tag’ ‣ concurrent_iterator enhancements ‣ subprocesses and apply ‣ ...
21. AST is JSON friendly
22. XML is still here
23. ‣ common attributes ‣ can be given to any expression
24. :if / :unless
25. :timeout
26. :on_timeout
27. ‣ :on_error ‣ much like begin / rescue... ‣ occurs when error is triggered ‣ error is thus not logged in error_journal
28. :on_error
29. :on_error
30. ‣ :on_cancel ‣ subprocess or participant triggered when expression gets cancelled ‣ unlike :on_error trigger happens when cancel is complete
31. :on_cancel
32. :forget
33. ‣ cursor / jump ‣ can now jump to a tag, a participant name or a subprocess name ‣ almost that ‘cursors as state machines’ feeling ‣ works with repeat (loop) as well
34. cursor / jump
35. ‣ directed commands ‣ cursor/repeat has jump/rewind/break/... commands ‣ until now these commands were only meant for the enclosing cursor/ repeat ‣ now with :tag and :ref, more precision is possible ‣ works with the iterator expression as well
36. rewind :ref => ‘tag’
37. skip :ref => ‘tag’
38. ‣ concurrent_iterator ‣ :times / :branches ‣ add_branches partner expression
39. concurrent_iterator
40. concurrent_iterator
41. ‣ ruote 0.9.x had the ‘eval’ expression ‣ evaluating segments of process ‣ ruote 2.0 has ‘apply’ ‣ same mission ‣ and more (yield)
42. vanilla apply
43. yield like apply
44. set ‘v:x’ => ‘y’
45. ‣ engine variables ‣ can be read from processes ‣ cannot be set from processes ‣ are thus on the same foot as participants (which are registered at the engine level)
46. engine vars
47. engine vars
48. ‣ more about process definitions and expressions http://ruote.rubyforge.org/expressions.html http://ruote.rubyforge.org/patterns.html
50. 2.0 projects
51. ‣ ruote-dm datamapper persistence http://github.com/jmettraux/ruote-dm ‣ ruote-ar activerecord persistence http://github.com/kennethkalmer/ruote-activerecord ‣ ruote-couch (coming soon) couchdb persistence http://github.com/kennethkalmer/ruote-couch
52. ‣ ruote-kit full blown ruote-rest evolution http://github.com/kennethkalmer/ruote-kit ‣ ruote-http tiny sinatra ruote webservice http://github.com/jmettraux/ruote-http
53. ‣ ruote-amqp amqp participants and listeners http://github.com/kennethkalmer/ruote-amqp ‣ ruote-fluo still in the run http://github.com/jmettraux/ruote-fluo
55. ‣ ruote [2.0] website http://ruote.rubyforge.org ‣ ruote mailing list http://groups.google.com/group/openwferu-users ‣ freenode.net IRC #ruote
56. many thanks to everyone in the community especially to the “ruedas y cervezas” participants ;-)