We want AWESOME CLI tool & development

Go Conference 2019 Spring
https://gocon.jp/2019-spring-sessions#h7-s-we-want-awesome-cli-tool--development

Transcript

1. We want AWESOME CLI
   tool & development
   Go Conference 2019 Spring
   @micnncim
   

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2. $ whoami
   @micnncim @micnncim
   University Student (CS/B4)
   No Job (Welcome job opportunity!)
   Blog: https://micnncim.github.io/
   

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3. CLI, UNIX, Go
   

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5. A Quarter-Century of Unix (1994)
   Write programs that do one thing and do it well.
   Write programs to work together.
   Write programs to handle text streams,
   because that is a universal interface.
   

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6. Why Go for CLI?
   ば
   ば
   

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7. What component?
   ば Argument/Flag/(Subcommand)
   ば I/O (Standard Stream)
   ば Exit Code
   

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8. What needed for awesome CLI?
   ば UX/DX
   ば
   ば
   ば
   ば
   

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9. Design and Test CLI
   

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10. Design & Test I/O
    ば fmt.Println()
    Testable
    ば io.Writer
    ば I/O interface
    

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11. Design I/O
    

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12. Test I/O
    

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13. Design I/O
    

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14. Design I/O
    From github/hub
    

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15. Design I/O
    From mitchellh/cli
    

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16. Test I/O
    ば bytes.Bu er
    

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17. Handling Exit Code
    ば error Exit Code 0
    ば Exit Code
    ば Exit Code error type
    

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18. Handling Exit Code
    From github/hub
    

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19. Test with golden files
    ば ( )
    .golden
    ば
    API .golden
    

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20. Test with golden files
    

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21. Test with golden files
    ば testdata/expect.golden
    

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22. Test with golden files
    

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23. Cross Platform
    

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24. Support Cross Platform
    ば Go Linux/macOS/Windows
    ば Utility
    

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25. Pkgs for Cross Platform
    ば Home Directory: mitchellh/go-homedir
    ば Open ( | URL): skratchdot/open-golang
    ば Color: mattn/go-colorable
    

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26. Pkgs for Cross Platform
    From
    mitchellh/go-homedir
    

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27. Build & Release CLI
    

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28. Build & Release
    ば $ go get potentially unstable, Go
    ば GitHub Release curl + tar + chmod?
    ば
    

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29. Build & Release
    ば mitchellh/gox:
    ば tcnksm/ghr:
    ば goreleaser/goreleaser:
    , , etc.
    

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30. GoReleaser
    ば YAML
    ば Homebrew
    ば CI easy
    

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31. GoReleaser: Build
    ば YAML
    ば
    DX
    

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32. GoReleaser: Changelog
    ば Changelog
    = UX
    

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33. GoReleaser: Package Manager
    ば Formula
    ば
    DX
    ば UX
    

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34. CI/CD
    ば tag push CI
    

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35. CI/CD
    ば GoReleaser dead simple
    GoReleaser dead simple
    

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36. Update
    ば
    ば CLI GUI
    ば rhysd/go-github-selfupdate tj/go-update
    

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37. Auto Update
    
    

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38. Document CLI
    

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39. Documentation
    ば Go
    ( | )
    ば
    ば ( )
    

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40. Demo
    ば GIF? SVG?
    ば troublesome
    ば asciinema + (asciicast2gif | svg-term-cli)
    

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41. Demo
    

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42. Develop Rich CLI
    

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43. Awesome CLI packages
    ば All in One
    ば Flag Parser
    ば Standard Stream
    ば Progress UI
    ば Con guration
    

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44. All in One
    ば urfave/cli 10,714
    ば spf13/cobra 11,958
    ば mitchellh/cli 966
    , ,
    , etc.
    

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45. All in One
    

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46. Flag Parser
    ば alecthomas/kingpin 2,431
    ば jessevdk/go- ags 1,458
    ,
    , ag/argument,
    ag parse
    

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47. Flag Parser
    

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48. Standard Stream
    ば manifoldco/promptui 2,803
    ば AlecAivazis/survey 1,144
    validation,
    Select, Con rm, Password UI
    UX Stdin UI
    Utility
    

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49. Standard Stream
    

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50. Progress UI
    ば cheggaaa/pb 1,878
    ば gosuri/uiprogress 1,400
    ば briandowns/spinner 734
    I/O ,
    Spinner UI
    

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51. Progress UI
    

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52. Configuration
    ば spf13/viper 8,467
    JSON/TOML/YAML/HCL
    Con g ,
    , Path
    

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53. Example
    

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54. micnncim/bitbrew
    ✔ Document, Demo
    

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55. micnncim/bitbrew
    ✔
    

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56. micnncim/bitbrew
    ✔
    

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57. micnncim/bitbrew
    ✔ Testable I/O
    

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58. micnncim/bitbrew
    ✔ Con g
    

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59. micnncim/bitbrew
    ✔ Rich UI
    

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60. micnncim/bitbrew
    ✔ Installation
    

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61. See also
    ば golang/go
    ば hashicorp/consul, terraform, nomad, packer, etc.
    

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62. @micnncim
    Thank you!
    

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