Carmel at YAPC::EU 2015

Transcript

1. Carmel
   Yet another CPAN dependencies management tool
   Tatsuhiko Miyagawa
   YAPC::EU 2015
   

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2. Me
   • MIYAGAWA, @miyagawa
   • San Francisco, CA, United States
   • Perl, Ruby
   

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3. Agenda
   • Why manage CPAN dependencies
   • Introduction of tools
   • Demo
   • Future Plans
   

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4. Carton
   Bundler(-ish) for Perl
   

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6. (quick recap)
   

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7.  @local>  cpanm  Poles  
   Installed  Poles-­‐1.0.tar.gz  
   @remote>  cpanm  Poles  
   Installed  Poles-­‐2.1.tar.gz
   

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9. “Updating CPAN modules
   broke my app”
   

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10. Takeaway
    • CPAN dependencies = Your app
    • Describe it
    • Manage it
    • Version Control it
    

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11. cpanfile
    

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12. cpanfile
    • DSL to describe CPAN dependencies
    • Version Range, Phases
    • a la Gemfile
    • Module::CPANfile
    • Supported by many tools (cpanm)
    

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13. requires  'Plack',  '1.001';  
    requires  'Mojolicious',  '==  6.17';  
    on  'develop'  =>  sub  {  
       requires  'Devel::NYTProf';  
    };  
    on  'test'  =>  sub  {  
       requires  'Test::More';  
       requires  'Test::mysql';  
    };
    

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14. requires  'Plack',  '1.001';  
    requires  'Mojolicious',  '==  6.17';  
    on  'develop'  =>  sub  {  
       requires  'Devel::NYTProf';  
    };  
    on  'test'  =>  sub  {  
       requires  'Test::More';  
       requires  'Test::mysql';  
    };
    

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15. requires  'Plack',  '1.001';  
    requires  'Mojolicious',  '==  6.17';  
    on  'develop'  =>  sub  {  
       requires  'Devel::NYTProf';  
    };  
    on  'test'  =>  sub  {  
       requires  'Test::More';  
       requires  'Test::mysql';  
    };
    

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16. >  cpanm  -­‐-­‐installdeps  .
    

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17. cpanm + cpanfile
    • Grabs latest versions that satisfy ranges
    • '== version' can pin versions
    • cpanmetadb/MetaCPAN SPOF
    

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18. Carton
    Bundler(-ish) for Perl
    

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19. Carton + cpanfile
    • Installs into ./local
    • Creates cpanfile.snapshot
    • Git friendly
    • carton  install  -­‐-­‐deployment
    

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20. requires  'Poles',  '1.0';  
    

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21.  @local>  carton  install  
    Installed  Poles-­‐1.0.tar.gz  
    @remote>  carton  install  -­‐-­‐deployment  
    Installed  Poles-­‐1.0.tar.gz
    

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23. Carton
    1.0 released in late 2013
    1.1 was in the development
    

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25. Carton
    • Slow for large installs
    • Relies on cpanm internals
    • Git support is hard
    • Update/Rollback is unreliable
    • -­‐-­‐deployment is confusing
    • carton  exec doesn't check on development
    

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26. Carmel
    Yet another Bundler for Perl
    

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27. Carmel
    • Same UI/UX with Carton
    • Different internals
    • Rewritten from scratch
    • Deeper understandings of how Bundler works
    • Fast and Reliable
    

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28. blib
    The core of Carmel
    

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29. How to build a CPAN module
    • Configure
    • Build
    • Test (Optional)
    • Install
    

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30. How to build a CPAN module
    • perl  Makefile.PL  
    • make  
    • make  test  
    • make  install
    

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31. ➜  perl  Makefile.PL    
    Checking  if  your  kit  is  complete...  
    Looks  good  
    Generating  a  Unix-­‐style  Makefile  
    Writing  Makefile  for  Try::Tiny  
    Writing  MYMETA.yml  and  MYMETA.json  
    ➜  make  
    cp  lib/Try/Tiny.pm  blib/lib/Try/Tiny.pm  
    Manifying  1  pod  document  
    

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32. ➜  perl  Makefile.PL    
    Checking  if  your  kit  is  complete...  
    Looks  good  
    Generating  a  Unix-­‐style  Makefile  
    Writing  Makefile  for  Try::Tiny  
    Writing  MYMETA.yml  and  MYMETA.json  
    ➜  make  
    cp  lib/Try/Tiny.pm  blib/lib/Try/Tiny.pm  
    Manifying  1  pod  document  
    

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33. blib/{lib,arch}
    Can be pushed to @INC  
    CPAN.pm does it for ages
    

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34. The idea
    • Builds all modules without installing them
    • Manages these "blib"s (call them artifacts)
    • Chooses artifact paths dynamically on dev
    • Freezes artifact paths statically on prod
    

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35. Carmel
    Written in a few hours as a hack.
    Turned into a module at Berlin QA Hackathon.
    

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36. DEMO
    

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37. Commands
    • carmel install
    • carmel list/tree
    • carmel exec
    • carmel package
    • carmel rollout
    • carmel inject
    

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38. Tools
    • carmel exec
    • Carmel::Setup
    • Carmel::Preload
    

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40. Current status
    • pre-1.0
    • Usable (I use it on cpanmetadb production)
    • Snapshot support in development
    

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41. >  cpanm  Carmel  
    

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42. >  cpanm  Carmel  
    Successfully  installed  Menlo-­‐1.9001  
    Successfully  installed  Carmel-­‐v0.1.25  
    2  distributions  installed  
    

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43. >  cpanm  Carmel  
    Successfully  installed  Menlo-­‐1.9001  
    Successfully  installed  Carmel-­‐v0.1.25  
    2  distributions  installed  
    

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44. Menlo
    

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45. Menlo
    "cpanm 2.0"
    

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46. cpanm
    • Loved by the users
    • Mixed feelings by the developer (me)
    • God class, Hard to refactor
    • Grown out of a pre-fatpack single script
    • Not extensible
    

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47. Menlo
    • Modular, Scriptable, Object-Oriented APIs
    • Plugin Hooks
    • uses CPAN::Common::*
    • Extracts the common bits (e.g. HTTP::Tinyish)
    • Still bootstrappable with fatpack/vendoring
    

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48. >  cpanm  Menlo  
    >  cpanm-­‐menlo  Plack
    

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49. Current status
    • github.com/miyagawa/cpanminus @ menlo
    • New features (static installs)
    • Pre big refactoring
    • No plugins
    

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50. 2.0 planned for QAH 2016
    ... but with continuous 1.9x releases
    

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51. github.com/miyagawa
    

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52. irc.perl.org #cpanm
    

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53. Thank you.
    Questions?
    

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54. FAQ
    • Why Carmel/Menlo?
    • 1.0/2.0 ETA?
    • Is Carton deprecated?
    • What's the purple thing in your avatar?
    

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