How not to fuckup with building mobile SDK and make clients happy

Presentation from GDG DevFest Nantes 2017
More information at: https://devfest.gdgnantes.com/

Abstract:
Are you working on the client library? Or design a public API for the module that is going to be used by other team or department?

In this session, Vitality will share his experience and key learnings from building a mobile SDKs for last 4 years.

Transcript

1. @zasadnyy
   With building the mobile SDK
   How not to Fuck Up
   Vitaliy Zasadnyy
   Head of Mobile @ GetSocial
   

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2. @zasadnyy
   Integrated SDK.
   But it doesn’t work.
   

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3. Developer.
   GDG Lead.
   Public Speaker.
   @zasadnyy
   

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7. SDK Lifecycle
   

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8. @zasadnyy
   SDK Lifecycle
   Develop
   1
   

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9. @zasadnyy
   

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10. @zasadnyy
    SDK Lifecycle
    Develop
    1
    

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11. @zasadnyy
    SDK Lifecycle
    Develop
    1
    Integrate
    2
    Support
    3
    Update
    4
    

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12. Develop
    1
    

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13. @zasadnyy
    Start shaping your API
    Use Cases
    Examples
    Integration Tests
    

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14. @zasadnyy
    Cost of fixing API
    

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15. @zasadnyy
    Cost of fixing API
    Spend 10x more time
    on line of examples
    comparing to
    production code
    

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16. @zasadnyy
    NOT SURE?
    DROP IT!
    

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17. @zasadnyy
    IS BETTER
    LESS CODE
    

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18. @zasadnyy
    Boilerplate ➡ Copy/Paste ➡ Bugs
    Why?
    

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19. 
    
    
    
    
    android:name="im.getsocial.sdk.invites.ImageContentProvider"
    android:name="im.getsocial.sdk.AppId"
    android:value="LuDPp7W0J4"/>
    
    
    
    
    
    
    
    
    
    GetSocial.init()
    

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20. 
    
    
    
    
    android:name="im.getsocial.sdk.invites.ImageContentProvider"
    android:name="im.getsocial.sdk.AppId"
    android:value="LuDPp7W0J4"/>
    
    
    
    
    
    
    
    
    
    

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21. @zasadnyy
    How to solve?
    AndroidManifest merging
    Gradle plugin
    Android Studio plugin
    …
    

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22. @zasadnyy
    Gradle plugin
    apply plugin: 'im.getsocial'
    getsocial {
    appId "LGa80P9790xsg4"
    }
    

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23. @zasadnyy
    Auto initialisation
    android:name="im.getsocial.AutoInitContentProvider"
    android:authorities="..."
    android:exported="false" />
    

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24. @zasadnyy
    IS BETTER
    LESS CODE
    

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25. @zasadnyy
    API SURPRISES
    AVOID
    

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26. @zasadnyy
    Avoid API surprises
    Thread.interrupted()
    Returns the current interrupted status
    and then clears it
    

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27. @zasadnyy
    Avoid API surprises
    

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28. @zasadnyy
    Avoid API surprises
    Thread.interrupted()
    Returns the current interrupted status
    and then clears it
    

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29. @zasadnyy
    Make API of your library
    as boring as possible
    - Chris Sells, Google
    

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30. @zasadnyy
    ?
    Library is crashing
    you app?
    

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31. @zasadnyy
    

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32. @zasadnyy
    CRASH HOST APP
    NEVER
    

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33. @zasadnyy
    GetSocial approach
    Rx
    Development Mode
    @Nullable / PMD / FindBugs / Lint
    

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34. @zasadnyy
    Rx chains
    Observable
    .just(MetaDataKey.APP_ID)
    .map(ValidateAppIdFunc.create())
    .flatMap(TrackInstallFunc.create())
    ...
    .subscribe((result) -> { ... },
    (throwable) -> {
    // all exceptions end up here
    }
    );
    

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35. @zasadnyy
    Rx chains
    Observable
    .just(MetaDataKey.APP_ID)
    .map(ValidateAppIdFunc.create())
    .flatMap(TrackInstallFunc.create())
    ...
    .subscribe((result) -> { ... },
    (throwable) -> {
    // all exceptions end up here
    }
    );
    

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36. @zasadnyy
    

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37. @zasadnyy
    INTERNALS
    HIDE
    

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38. @zasadnyy
    Hide internals
    

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39. @zasadnyy
    Hide internals
    Use .internal package
    Keep everything private by default
    

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40. @zasadnyy
    There is much more!
    

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41. Integrate
    

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42. @zasadnyy
    ?
    What is important
    to developers?
    

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43. @zasadnyy
    SIZE
    

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44. @zasadnyy
    List information about
    Library size
    Method count
    Proguard rules
    

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45. @zasadnyy
    COMPATIBILITY
    

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46. @zasadnyy
    Keep compatibility
    Select minimum supported platform version.
    After detailed market research
    Update maximum supported version.
    Continuously
    

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47. @zasadnyy
    SUPPORT
    

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48. @zasadnyy
    Give a voice to your users
    GitHub issue tracker
    Intercom
    Support email
    …
    

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49. @zasadnyy
    Get ready to repetitive
    questions
    

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50. @zasadnyy
    DOCS
    

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51. @zasadnyy
    Documentation is like sex.
    Even bad is better than nothing
    

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52. @zasadnyy
    Key parts
    Step by step tutorials
    Product guides
    API Reference
    

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53. @zasadnyy
    

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54. @zasadnyy
    

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55. @zasadnyy
    

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56. @zasadnyy
    What is wrong with snippet?
    CurrentUser user = getSocial.getCurrentUser();
    

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57. @zasadnyy
    What is wrong with snippet?
    CurrentUser user = getSocial.getCurrentUser();
    

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58. @zasadnyy
    ALL SNIPPETS MUST
    COMPILE
    

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59. @zasadnyy
    Better snippet
    import im.getsocial.sdk.GetSocial;
    import im.getsocial.sdk.CurrentUser;
    ...
    CurrentUser user =
    GetSocial.getInstance().getCurrentUser();
    

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60. @zasadnyy
    There is more
    GitHub Wiki, MkDocs, Jekyll
    Google Developer Documentation
    Style Guide
    

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61. @zasadnyy
    ?
    Favourite source
    of copy / paste code?
    

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62. @zasadnyy
    

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63. @zasadnyy
    DEMOS
    

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64. @zasadnyy
    Demo apps
    Make demos well documented
    Keep SDK integration code separated
    

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65. Support
    

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66. @zasadnyy
    ?
    You’ve got support request.
    Now what?
    

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67. @zasadnyy
    Two types of problems
    Integration time
    problems
    End-user side
    problems
    

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68. @zasadnyy
    Solving integration time problems
    Easy way to get SDK version
    Unique log tag
    Debug SDK configuration
    Actionable errors
    

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69. @zasadnyy
    Debug SDK configuration
    adb shell setprop \
    debug.getsocial.sdk.app com.demo
    

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70. @zasadnyy
    Actionable errors
    public class GetSocialException
    extends RuntimeException {
    private final int _errorCode;
    …
    }
    

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71. @zasadnyy
    Actionable errors
    public class GetSocialException
    extends RuntimeException {
    private final int _errorCode;
    …
    }
    

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72. @zasadnyy
    Solving end-user side problems
    Comprehensive logs
    Errors analytics
    

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73. @zasadnyy
    Solving end-user side problems
    void trackError(GetSocialException exception) {
    ...
    AnalyticsTrackManager.trackAnalyticsEvent(
    AnalyticsEventDetails.Name.SDK_ERROR,
    eventProperties);
    }
    

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74. @zasadnyy
    

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75. @zasadnyy
    

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76. @zasadnyy
    s
    THINK ABOUT SUPPORT
    AHEAD
    

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77. Update
    

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78. @zasadnyy
    ?
    Why developers update
    SDKs?
    

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79. @zasadnyy
    Update. Build. And…
    

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80. @zasadnyy
    

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81. @zasadnyy
    UPDATES
    SMOOTH
    

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82. @zasadnyy
    Backward compatibility
    Use @Deprecation cycle
    /**
    * @deprecated use {@link #getAllIdentities()} instead.
    * Method will be removed in SDK v5.0.0.
    */
    @Deprecated
    public List getIdentities() { ... }
    

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83. @zasadnyy
    Semantic versioning
    v4.5.1
    Major Minor Bugfix
    

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84. @zasadnyy
    Versioned packages
    import okhttp3;
    import im.getsocial.sdk6;
    

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85. @zasadnyy
    Versioned packages
    import okhttp3;
    import im.getsocial.sdk6;
    Partial transition
    A/B testing
    

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86. @zasadnyy
    Changelog
    Fixed issues
    New features
    Deprecations
    Upgrade guide
    

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87. @zasadnyy
    

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88. To sum up
    

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89. @zasadnyy
    PER APP
    17 SDKs
    Source: Safe SDK
    

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90. @zasadnyy
    SDK Lifecycle
    Develop
    1
    

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91. @zasadnyy
    SDK Lifecycle
    Develop Integrate Support Update
    1 2 3 4
    

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92. @zasadnyy
    API can be you biggest asset
    of liability
    - Joshua Bloch
    Put yourself
    in your customer’s shoes
    - Cesare Rocchi
    

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93. @zasadnyy
    Happy dog
    Make developers
    happy again.
    

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94. @zasadnyy
    @zasadnyy / zasadnyy.com
    Questions?
    Merci!
    

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