RubyConf India 2015: Diving in the Unknown depth of a project

As a developer, diving in a new code base is not uncommon: you've just been hired, you change of project, you want to help an open source project, the open source library your project depends on is buggy, etc. It's like entering in a underwater cave, you don't know the treasures or the monsters you'll find there, neither if the path is treacherous or if it's a true labyrinth where you'll get lost. You can prepare yourself, you can plan your visit, you can equip yourself, you can survive and find the gem you're looking for...

Transcript

1. Diving in the
   Unknown depth
   of a project
   Andy Spearing © 2009
   

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2. _toch
   toch
   Hi, I'm
   Christophe
   

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3. @matylda © 2011
   Intro
   

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4. @matylda © 2011
   The most
   common
   task
   

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5. continuous typing
   

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7. but
   continuous reading
   Jono Witts © 2008
   

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8. Each written line
   is read
   at least 1 time
   Gavin St. Ours © 20013
   

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9. ● 300 dev days
   ● 14633 LOC
   ● 634595 Changed lines
   ● → 634595 / 14633 ~ 43 changed LOC / LOC
   

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10. For 1 final line,
    I read at least
    43 lines.
    

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12. How to
    Dive
    into a project
    Stuart Hamilton © 2008
    

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13. DO NOT
    Wander
    without a plan
    Felix Esteban © 2004
    

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14. Journey
    Needs
    Plan
    Peter Southwood © 20011
    

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15. Plan
    1. Goal
    2. Map
    3. Equipment & Dive
    4. Next?
    Peter Southwood © 20011
    

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16. 1.
    Goal
    Peter Southwood © 20011
    

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17. ➔ fix a bug
    ➔ implement a feature
    ➔ write some doc
    ➔ style the code
    ➔ refactor a small piece of code
    ➔ simply use it
    

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20. ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:878:in `initialize': Connection refused -
    connect(2) (Errno::ECONNREFUSED)
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:878:in `open'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:878:in `block in connect'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/timeout.rb:52:in `timeout'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:877:in `connect'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:862:in `do_start'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:851:in `start'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:313:in `open_http'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:708:in `buffer_open'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:210:in `block in open_loop'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:208:in `catch'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:208:in `open_loop'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:149:in `open_uri'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:688:in `open'
    from ~/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/open-uri.rb:34:in `open'
    from -e:1:in `'
    

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21. 2.
    Map
    Peter Southwood © 20011
    

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22. Find the Map
    ➔ Repository URI
    ➔ Project URI
    ➔ Intro Doc: README
    

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23. Find the Map
    ● https://github.com/ruby/ruby
    ● https://bugs.ruby-lang.org/
    ● https://github.com/ruby/ruby/blob/trunk/
    README.md
    

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24. Find the Legend
    

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25. a
    Legend
    

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26. Find the Legend
    ➔ CONTRIBUTING Guideline
    

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27. Find the Legend
    ➔ CONTRIBUTING Guideline
    https://github.com/ruby/ruby/blob/trunk/
    CONTRIBUTING.md
    

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28. Find the Legend
    ➔ CONTRIBUTING Guideline
    https://github.com/ruby/ruby/blob/trunk/
    CONTRIBUTING.md
    

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29. Find the Legend
    ➔ CONTRIBUTING Guideline
    ➔ Directory Structure
    

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30. Find the Legend
    ➔ CONTRIBUTING Guideline
    ➔ Directory Structure
    

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31. Find the Legend
    ➔ CONTRIBUTING Guideline
    ➔ Directory Structure
    ➔ Talk to other contributors, maintainers
    

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32. Find the Legend
    ➔ CONTRIBUTING Guideline
    ➔ Directory Structure
    ➔ Talk to other contributors, maintainers
    ➔ Participate to the dev meeting
    

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33. If blocked?
    ➔ ASK!
    

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34. Boris Dimitrov © 20009
    3.
    Equipment
    & Dive
    

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35. Get a Toolbelt
    ➔ Pick an Editor
    

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37. Get a Toolbelt
    ➔ Pick an Editor
    ➔ Bundle & Run Tests
    

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38. Get a Toolbelt
    ➔ Pick an Editor
    ➔ Bundle & Run Tests
    ➔ Others
    

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39. Get a Toolbelt
    ➔ ST3
    ➔ Apply a Patch & Use it
    ➔ MRI WIKI DeveloperHowto
    ➔ Sign up to Ruby Redmine
    

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40. Use your Toolbelt
    ➔ Run the App & Use it
    

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42. Use your Toolbelt
    ➔ Run the App & Use it
    ➔ Read & Edit the Code
    

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43. ➔ Find proxy management into open-uri.rb
    ➔ Understand how OpenURI.open_http works
    ➔ Spot the bug
    ➔ Fix it
    

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45. Use your Toolbelt
    ➔ Run the App & Use it
    ➔ Read & Edit the Code
    ➔ Report a bug
    ➔ Submit a contribution
    

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47. If blocked?
    ➔ ASK!
    

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48. 4.
    Next?
    Peter Southwood © 20011
    

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49. How long?
    ➔ Keep it reasonable at first
    ➔ From ½ to 1 day
    

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50. Find Next Goal
    ➔ Fix a bug
    ➔ Develop a feature
    ➔ Run Static Analysis Tools
    ➔ Review a PullRequest
    

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51. Iterate
    ➔ :)
    Jean-Marc Kuffer © 2007
    

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52. If blocked?
    ➔ ASK!
    

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53. Outro
    1. Goal
    2. Map
    3. Equipment & Dive
    

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54. ?
    _toch
    toch
    

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