Android Engineering for Scale

Droidcon London 2014 & Droidcon NYC 2015

Transcript

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2. Android Engineering
   for Scale
   Jamie McDonald
   

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3. What is scale?
   In the context of mobile development
   title, date, 01 of 10
   

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4. Subtitle
   4M Android downloads / month
   175M monthly listeners
   title, date, 01 of 10
   

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5. title, date, 01 of 10
   

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6. title, date, 01 of 10
   Codebase
   

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7. Ball of Mud
   title, date, 01 of 10
   

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8. Layered Architecture
   title, date, 01 of 10
   

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9. Featurised Architecture
   title, date, 01 of 10
   

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10. Layers
    

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11. Feature Packages
    

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12. Feature Packages
    STREAM
    StreamAdapter
    StreamFragment
    StreamModule
    StreamOperations
    StreamStorage
    StreamItemPresenter
    

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13. Lava Layers
    title, date, 01 of 10
    “Successive, well intentioned,
    changes to architecture throughout
    the lifetime of an project can lead
    to a fragmented and hard-to-
    maintain code base”
    The Lava Layer Anti-pattern
    

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14. SPOCCER
    Screen Presenter Operations Controller Command
    EntityState Repository
    

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15. Subtitle
    Reactive
    Programming
    title, date, 01 of 10
    Rx
    

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16. Branches
    title, date, 01 of 10
    <>
    branch
    <>
    master
    <>
    origin/master
    

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17. master
    Branch by Abstraction
    title, date, 01 of 10
    abstraction
    layer
    <> <>
    Martin Fowler: Branch by Abstraction
    

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18. master
    Branch by Abstraction
    title, date, 01 of 10
    abstraction
    layer
    <>
    Martin Fowler: Branch by Abstraction
    

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19. master
    Branch by Abstraction
    title, date, 01 of 10
    <>
    Martin Fowler: Branch by Abstraction
    

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20. master
    Trunk-based Development
    title, date, 01 of 10
    feature-B .isEnabled()
    .isEnabled()
    feature-A
    .isEnabled()
    feature-C
    Trunk-based Development
    

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21. if (flags.isEnabled(Feature.BRAND_NEW_FEATURE)) {
    return newThing;
    } else {
    return oldThing;
    }
    title, date, 01 of 10
    Feature Flags
    

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22. Modules
    title, date, 01 of 10
    MAIN REPO
    SINGLE REPO
    ANDROID-KIT
    PROPELLER
    LIGHTCYCLE
    SKIPPY PLAYER
    

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23. Users
    title, date, 01 of 10
    

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24. Subtitle
    End-to-End
    Development
    title, date, 01 of 10
    

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25. Android iOS
    SoundCloud API
    

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26. API Mobile
    Mobile API
    Android iOS
    

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27. Subtitle
    title, date, 01 of 10
    {
    "id":612849,
    "kind":"user",
    "permalink":"bazan",
    "username":"David Bazan",
    "uri":"https://api.soundcloud.com/users/612849",
    "permalink_url":"http://soundcloud.com/bazan",
    "avatar_url":"https://i1.sndcdn.com/avatars-000030728315-
    oe5uld-large.jpg?e76cf77",
    "country":"United States",
    "first_name":"David",
    "last_name":"Bazan",
    "full_name":"David Bazan",
    "description":"Known for his work fronting the enigmatic
    rock band Pedro the Lion, David Bazan\u2019s emotionally
    charged narratives, eye for telling detail, and mournful
    voice have more in common with J.D. Salinger\u2019s
    \u201cNine Stories\u201d or Flannery O\u2019Connor\u2019s
    \u201cWise Blood\u201d than with the usual lyrical slant of
    popular music. Bazan is a gifted storyteller, weaving
    parables of spiritual conflict, suburban ennui, and personal
    surrender into magnetic, well-crafted songs.\r\n\r\nHis debut
    solo full-length album, Curse Your Branches (out now on
    Barsuk), is a masterwork by a modern American poet at the
    height of his powers. Paste Magazine called him one of the
    \u201c100 Best Living Songwriters\u201d. This record is the
    deepest and most explicit exploration of his struggles with
    faith and a meditation on all things passed between the
    generations.",
    "city":"Seattle",
    [...]
    }
    {
    "collection":[
    "hip hop",
    "chill",
    "electronic",
    "deep house",
    "party",
    "love",
    "rap",
    "happy",
    "study",
    "techno",
    "indie rock",
    "dubstep",
    "r&b",
    "relax",
    "country",
    "pop",
    "edm",
    "reggae",
    "house",
    "workout",
    "soundtrack",
    "reggaeton",
    "piano",
    "dance",
    "remix",
    "alternative",
    "summer",
    "instrumental",
    "rock",
    "morning",
    "funk",
    "classical",
    [...]
    }
    SoundCloud API Mobile API
    

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28. Staying Connected
    

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29. Team
    title, date, 01 of 10
    

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30. Mobile Team
    Other Engineering
    Android iOS
    Platform
    Teams
    

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31. Feature Teams
    Core Engineering
    Android iOS
    

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32. Core Engineering
    Android iOS
    Feature Teams
    

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33. title, date, 01 of 10
    

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34. title, date, 01 of 10
    

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35. Enabling Involvement
    

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36. Subtitle
    Collective Values
    title, date, 01 of 10
    

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37. title, date, 01 of 10
    Pairing & Pull Requests
    

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38. title, date, 01 of 10
    ACCEPTANCE TEST
    UNIT TEST
    CODE
    

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39. Subtitle
    title, date, 01 of 10
    @Inject @LightCycle ActionBarUtil actionBarUtil;
    @Inject @LightCycle PlayerController playerController;
    public MainActivity() {
    [...]
    }
    Unit Testing
    

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40. title, date, 01 of 10
    Acceptance Testing
    

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41. Release Train
    title, date, 01 of 10
    BETA
    257 258 259
    258-beta 259-beta
    RELEASE
    

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42. title, date, 01 of 10
    UNIT
    TESTS
    BUILD PROMOTE
    ACCEPTANCE
    TESTS
    Continuous Integration
    

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43. title, date, 01 of 10
    Featurised, layered architecture
    Shared practices: reactive programming
    Feature teams & end-to-end development
    Shared values: testing
    Trunk-based development
    Summary
    

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44. soundcloud.com/jobs
    Thank you, NYC!
    

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