Arrrr Me Hearty! Sailing the Seas of DRb in a Shoe

You insouciant scalawags will share the experience of a lifetime as you play a game built atop DRb and Shoes based generally upon the phenomenon known as Spaceteam! Except with Pirates!!

Join us as we skirt the treacherous shoals of DRb, learning techniques that will allow you to navigate it like you were born on the high seas!

Dig for the buried treasure of Rinda to discover the mysterious secrets of the RingProvider and TupleSpace!

Storm the fortress of Shoes and learn about it’s secret trapdoors and avoid the dungeons!

Team up with your fellow attendees to plunder the high seas and avoid the Curse of the Live Demo! Yarrrr….☠

Transcript

1. ARRRR ME HEARTY! Sailing the Seas of DRb in a Shoe Davy Stevenson Eric Hodel Rein Henrichs @davystevenson @drbrain @reinh RubyConf 2013
2. Spaceteam? Who has played? Pleiades by Jim Keller
3. Spaceteam trailer
4. Why DRb? Easy Interprocess Communication Send and Get Data Peer to Peer Red Beach by alphadesigner
5. Why Rinda? Flexible Automatic discovery No explicit destination? Throw it in the tuplespace Farmhouse and Roosting Birds at Dusk by Trey Ratcliff
6. Why Shoes? Needs some love and attention Perfect showcase for distributed code Support non-web Ruby development! Freestyle Converse by Daniele Margaroli
7. Why Pirates? Yarrr! Mutiny by Shane Gorski
8. Preparation Install jruby (1.7.4-6 all should work) Install shoes4 $ git clone https://github.com/shoes/shoes4 $ git checkout 7d0a1ee $ gem build shoes.gemspec $ gem install shoes-4.0.0.pre1 $ alias shoes4='/path/to/shoes4/bin/shoes' Install pirate_game $ gem install pirate_game
9. Preparation Also in pirate_game README! https://github.com/davy/pirate_game
10. DRb RMI for Ruby Written by Masatoshi SEKI require ‘drb’ Remote objects act like local objects It’s “Ruby Throated” Tuesday! by MrClean1982
11. Remote Array Server array = [] # share the array DRb::DRbServer.new nil, array # print the URI (we let DRb pick) puts DRb.uri # wait for ^C DRb.thread.join
12. Remote Array Peer # create remote array reference remote_array = DRbObject.new_with_uri ARGV.shift # append to remote array remote_array << "a" remote_array.push "b", "c"
13. Remote Array Peer # create remote array reference remote_array = DRbObject.new_with_uri ARGV.shift puts remote_array.join ", " # => a, b, c
14. Rinda Linda for Ruby Model for distributed programming require ‘rinda/ tuple_space’ Stores tuples with arbitrary data write, take, read Quasicabinet by Aranda\Lasch
15. Tuple Space # blocking operation with template @ts.take [:button, "Keel", (now...now + 30), nil] # writing a matching tuple unblocks @ts.write [:button, "Keel", Time.now.to_i, DRb.uri]
16. Service Discovery Rinda::RingFinger, Rinda::RingServer TupleSpace for registry Broadcast, unicast, multicast (Ruby 2.1) Rinda::RingProvider Wrapper for advertisement
17. Shoes Created by _why Simple cross- platform GUI toolkit for Ruby Shoes4 is an all- Ruby rewrite Still under active development Blue Power! by Éole Wind
18. Shoes Manual Layout Input elements Drawing Animate / Move / Events http://shoesrb.com/manual/Hello.html
19. Display Issues Not all movement methods have been implemented on all types of objects Can move, but not displace Width/height =( Show/hide/toggle missing =(
20. Animations Animations run in parallel Need to manually manage them start, stop, remove PROTIP™: Separate drawing from animation
21. Give Back Complicated Shoes app highlights regressions Use game to detect & fix issues
22. Open Source Three Gems! github.com/davy/ pirate_command github.com/davy/ shuttlecraft github.com/davy/ pirate_game Coast Guard by Mike Baird
23. pirate_command PirateCommand.generate => "Swab the Poop Deck" PirateCommand.action => "Batten" PirateCommand.thing => "Main Sail" PirateCommand.exclaim => "Ahoy" PirateCommand.exclaim! => "Shiver me Timbers!"
24. pirate_command github.com/davy/pirate_command
25. shuttlecraft Create distributed systems with Rinda Simplifies registration Keeps track of registered clients Easily send messages
26. shuttlecraft github.com/davy/shuttlecraft
27. pirate_game Play the game!
28. pirate_game github.com/davy/pirate_game
29. Game Architecture? Does exactly what the GM instructs Game Master Game Handles all logic Issue cmds to game, game sends response
30. That’s no fun! Distributed services FTW Lightning by Fadzly Mubin
31. Game Architecture Registration Layout generation Issuing actions & gathering responses
32. Yay Diagrams! Game Game Master Rinda Tuplespace
33. Registration
34. Registration write [:name, ‘Foo’, uri’]
35. Registration write write [:name, ‘Foo’, uri’] [:name, ‘Bar’, uri’]
36. Registration write write write [:name, ‘Foo’, uri’] [:name, ‘Bar’, uri’] [:name, ‘Baz’, uri’]
37. Registration write write write [:name, ‘Foo’, uri’] [:name, ‘Bar’, uri’] [:name, ‘Baz’, uri’] read_all
38. Layout Generation GM sends each game their bridge and list of all bridge items my_items all_items my_items all_items direct DRb
39. Action & Response
40. Action & Response watch for actions take (blocks)
41. Action & Response ‘Haul the Keel’ watch for actions take (blocks)
42. Action & Response watch for button click take (blocks) watch for actions take (blocks)
43. Action & Response watch for button click on button click [:button, ‘Keel’, timestamp, from] write take (blocks) watch for actions take (blocks)
44. Action & Response watch for button click [:button, ‘Keel’, timestamp, from] take (blocks) watch for actions take (blocks)
45. Action & Response watch for button click watch for actions take (blocks) write [:action, ‘Keel’, timestamp, from]
46. Action & Response watch for button click watch for actions take (blocks) [:action, ‘Keel’, timestamp, from]
47. Action & Response watch for button click watch for actions
48. Architecture Diagram mothership game_master client client_app master_app shuttlecraft
49. Enough Jibber Jabber Let’s get to the important parts GAME TIME Shut up you fool! by Andre Vandal
50. Preparation (again) Install jruby (1.7.4-6 all should work) Install shoes4 $ git clone https://github.com/shoes/shoes4 $ git checkout 7d0a1ee $ gem build shoes.gemspec $ gem install shoes-4.0.0.pre1 $ alias shoes4='/path/to/shoes4/bin/shoes'
51. Install Install pirate_game $ gem install pirate_game
52. Networking Theoretically this should work on conference wifi *But* for best results use a personal access point
53. RingServer Someone needs to run a ringserver $ ring_server But not too many Try not to screw it up We are working on it
54. Game Master Only one needed per game Pick a good name If GM crashes, game is stranded =(
55. Pirate Game! 1* to 4 players *Totally a ‘feature’ not a bug
56. Find Your Game GMs are found by Rinda service discovery
57. Find Your Game ISSUE: If join fails you will not receive an error message and will enter empty disconnected pub =(
58. Pirate Pub Chat with your friends in the Pirate Pub* *Yes, you have to click the ‘Send’ button. No keybindings?!? =(
59. Pirate Pub ISSUE: At the moment the GM needs to trigger each stage. Future development should switch over to Spaceteam-like mechanism where each player indicates that they are ready to proceed
60. Sail the High Seas Keep the ship afloat! Work together to man the ship Beware of bad weather!
61. Security DRb Priorities: Transparency Easy of use … Security Pirates by Adrien Sifre
62. Full Access Clients can do anything Get remote nil instance_eval github.com/drbrain/drb-worm
63. Message-level Security DRb::DRbServer::INSECURE_METHOD Opt-out $SAFE Relies on tainting
64. DRb over UNIX Socket Restricted to one host Filesystem permissions control access No network access
65. Access Control List Deny or allow by IP address and range Difficult to manage No privacy
66. DRb over SSL X509 certificate Full privacy Difficult to manage
67. chroot Filesystem sandbox Can’t write outside Can still consume CPU, create processes
68. Best Practices Verify your peers Limit accessibility Use a private network
69. drbdump tcpdump for DRb Message sends Message latency Message allocations Colorful toy trucks parked together in rows by Horia Varlan
70. Problems Out-of-order TCP mDNS Ruby 2.1 No filtering IPv6 (bug)
71. Running Basic drbdump Summary of 10,000 messages drbdump -q -n -c 10000 Listen only on loopback drbdump -i lo0
72. Timestamp 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
73. Source 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
74. Message-send 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
75. Receiver 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
76. Message Name 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
77. Arguments 17:34:49.546074 "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913", 70180390657240). respond_to?(:update, false)
78. Timestamp 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
79. Destination 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
80. Message-result 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
81. Source 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
82. Status 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
83. Result Object 17:34:49.546531 "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" success: true
84. Exception 17:34:49.563440 "druby://192.0.2.1:60929" ⤂ "druby://192.0.2.1:60920" exception: #<LocalJumpError: break from proc-closure>
85. Exception Object 17:34:49.563440 "druby://192.0.2.1:60929" ⤂ "druby://192.0.2.1:60920" exception: #<LocalJumpError: break from proc-closure>
86. Easy to Match "druby://192.0.2.1:60919" 㱺 ("druby://192.0.2.1:60913" "druby://192.0.2.1:60919" ⾨ "druby://192.0.2.1:60913" "druby://192.0.2.1:60929" 㱺 ("druby://192.0.2.1:60920" "druby://192.0.2.1:60929" ⤂ "druby://192.0.2.1:60920"
87. Statistics Output Basic statistics Packets, messages, results Message statistics Allocations, latency Peer statistics Latency
88. Basic Statistics 1508 total packets captured 0 Rinda packets captured 56 DRb packets captured 30 messages sent 26 results received 2 exceptions raised
89. Message Statistics Messages sent min, avg, max, stddev: call (1 args) 10 sent; 3.0, 6.2, 19.0, 6.7 allocations; 0.285, 1.479, 7.258, 2.171 ms
90. drbdump Diagnostics Find message spam Find hanging calls Verify expected behavior
91. Future Want to pitch in? Wilma was here by zanzibar
92. Group Activities Raid a ship? Survive a hurricane? Steer ship with the wheel
93. Character Generation Build a pirate? Select: Beard Parrot Eyepatch Hair
94. Infrastructure Improvement Automatic Integrated Game Master Better Error Handling Easy Game Restart
95. Play! Contribute! Thanks! =D The Flying Dutchman by Scott Smith