Build a Cross-Platform Web API CLI in 15 minutes with Mruby-CLI

Thanks to web APIs, we can extend any web apps with simple Ruby CLI: listing open pull requests, or tweeting directly from the terminal.

Unfortunately, distributing Ruby CLIs is complicated. So many runtimes to support, so hard to guarantee compatibility of gems on every platforms.

With mruby-cli, you can easily build an API CLI in mruby, a Ruby sibbling, and distribute it for every major platforms.

In this talk, we'll show how quickly you can build and distribute a such CLI with mruby-cli.

GitHub Repository:
- mruby-cli https://github.com/hone/mruby-cli
- mruby-web_api https://travis-ci.org/toch/mruby-web_api
- github_status https://github.com/toch/github_status

Screencasts of the live coding made during the talk https://gfycat.com/tochgif/rubyconf_ph_2016

Transcript

1. Building
   a cross-platform API CLI
   in 15 minutes
   

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2. toch
   _toch
   Magandang araw!
   Ako si Christophe.
   

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5. Google Trend of the keywords Web API
   

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8. GitHub -> Hub
   Heroku -> Heroku Toolbelt
   AWS -> aws-cli
   Trello -> trello_cli
   Slack -> slack-cli
   ...
   

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10. Cross Toolchain?
    

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11. Cross Toolchain? ¯\_(ツ)_/¯
    

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13. (╯°□°）╯︵ ┻━┻ ┬──┬
    

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21. $ gem install heroku
    

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25. $ GOOS=linux GOARCH=amd64 go build
    $ GOOS=windows GOARCH=amd64 go build
    $ GOOS=darwin GOARCH=amd64 go build
    

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28. We shouldn't
    stop there!
    

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29. + =
    https://github.com/hone/mruby-cli
    mruby-cli
    

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30. → Ruby
    → Performance
    → No Require
    → Binary for each platform/arch
    → Simple to compile & release
    → CLI apps framework
    Mruby-cli talk at RubyKaigi 2015
    Goals
    

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31. Team
    

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33. → ISO/IEC 30170:2012 standard
    → Compatible with Ruby 2.1 core API
    → No Built-in File/Socket/IO
    → not threadsafe, no Thread
    → procs/blocks
    → metaprogramming
    → monkey patching
    → literals
    → easy to bind to C-ABI compatible lib
    

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34. Gotchas:
    → no stdlib
    → native ext have to support cross-
    compilation
    → no Rubygems, but mrbgems-list
    

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38. Safe Live Coding:
    Hello RubyConf Ph
    

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39. Safe Live Coding:
    Advanced Scaffold
    

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40. A real example:
    ~/my_repo/ $ github_status
    Success
    

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41. GitHub Repository:
    $ git config --get remote.origin.url
    git@github.com:toch/my_repo.git
    

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42. Current Branch Name:
    $ git symbolic-ref HEAD
    refs/heads/current_branch
    

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43. Corresponding Pull Request:
    GET /repos/toch/my_repo/pulls
    ?head=toch:current_branch
    

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44. GitHub Status
    GET /repos/toch/my_repo
    /commits//status
    

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45. Safe Live Coding:
    GitHub Status
    

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46. Let's build CLI in Ruby <3!
    toch
    _toch
    hone/mruby-cli
    toch/mruby-web_api
    toch/github_status
    

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