Multiple Developers, One App: How to Not Break Everything

Most of us started developing mobile apps individually and many work professionally as the lone Android engineer on an app. But as the saying goes, “If you want to go fast, go alone. If you want to go far, go together.”

In this talk, we’ll explore what it takes to share a large mobile app codebase with a team of developers without breaking everything. From laying a solid foundation, to ensuring code quality, and automating things nobody wants to do, we’ll learn how to manage the increasing complexity of today’s Android apps as a team.

Transcript

1. Mul$ple Developers, One App
   How to Not Break Everything
   by Andy Dyer
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7. How to Not Break Everything
   • Laying the founda/on
   • Ensuring code quality
   • Automa5ng things no one wants to do
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8. Laying the Founda/on - Organiza/on
   • Ver%cal, feature focused teams
   • Agile Stuff™
   • Weekly pla• Lots of chat and ad hoc screen share sessions
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9. Laying the Founda/on - Project Structure
   • Separate repos for core business logic and apps
   • Package per feature
   • Feature flags to enable/disable func9onality
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10. Laying the Founda/on - Build Types
    productFlavors {
    alpha {
    // Upload to Crashlytics for QA testers
    }
    beta {
    // Upload to Crashlytics for beta testers
    }
    prod {
    // Release to Google Play
    }
    }
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11. How to Not Break Everything
    • Laying the founda0on
    • Ensuring code quality
    • Automa0ng things no one wants to do
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12. Ensuring Code Quality - Common Style
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13. Ensuring Code Quality -
    Code Reviews
    • Pull requests with at least one reviewer
    before being merged into develop
    branch
    • Mul9ple reviewers for significant
    changes
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14. Ensuring Code Quality - Automated Tes6ng
    • Architect for tes-ng
    • Dependency injec-on to group & isolate related components
    • MVP or similar pa=ern
    • Unit test as much as possible, Espresso for UI tests
    • Con-nuous integra-on server for building latest source and
    running tests
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15. Ensuring Code Quality - Alpha & Beta Tes9ng
    • QA team runs automated integra1on tests and performs
    targeted manual tests as necessary
    • Beta testers help iden1fy any cri1cal bugs prior to release
    • Staged rollout on Google Play for final release
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16. git rebase develop
    Early and o*en
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17. How to Not Break Everything
    • Laying the founda0on
    • Ensuring code quality
    • Automa'ng things no one wants to do
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18. Automa'ng Things No One Wants to Do - Git Hooks
    • Ensure code compiles before each commit
    • Ensure unit and instrumenta5on tests pass before each push
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19. Automa'ng Things No One Wants to Do - GitHub Hooks
    • Change Jira ,cket status to "Next Build" when pull request is
    merged
    • No,fy chat room when a pull request is opened, merged, etc.
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20. Automa'ng Things No One Wants to Do - Gruel Plugin
    • No$fy a HipChat channel with a specific message
    • Transi$on Jira issues matching a JQL filter to another status and
    update fields
    • Increment version numbers in a gradle.proper$es file
    • Specify a naming paDern for *.jar and *.apk files
    • Upload an *.apk file to Crashly$cs
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21. Gruel Plugin - No.fy HipChat
    hipchat {
    auth_token = '{AUTH TOKEN}'
    }
    task notifyHipchat(
    type: com.glasstowerstudios.gruel.tasks.hipchat.HipChatNotificationTask) {
    // Can be one of: ['purple', 'red', 'green', 'yellow', 'gray', 'random']
    color = 'yellow'
    message = "Your message here. You can include simple html"
    channelName = "Name of channel to notify"
    }
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22. Gruel Plugin - Transi/on Jira Issues
    task jiraUpdate(
    type: com.glasstowerstudios.gruel.tasks.jira.JiraTransitionTask) {
    userName = JIRA_USERNAME
    password = JIRA_PASSWORD
    jiraRootUrl = 'https://COMPANY.atlassian.net'
    jql = 'project = "PROJECT_NAME" AND status = "CURRENT_STATUS"'
    toStatus = 'NEW_STATUS'
    fieldUpdates = ['customfield_123': 'Updating a custom field',
    'customfield_456': 'Updating another custom field']
    }
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23. Gruel Plugin - Increment Version
    // Specifies an integer that is monotonically increasing with each
    // new version.
    PROJECTNAME_VERSION_CODE
    // Specifies a human-readable string that is used to represent a
    // version number to users (e.g. "3.0.0").
    PROJECTNAME_VERSION_NAME
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24. Gruel Plugin - Naming APK Files
    apply plugin: 'gruel'
    gruel {
    archiveName "%appName%", "%version%", "%codeName",
    "%buildType%", "%commitHash%"
    version android.defaultConfig.versionName
    commitHash gitSha()
    }
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25. Gruel Plugin - Crashly1cs Upload
    android {
    productFlavors {
    alpha {
    gruel.uploadUsing 'crashlytics', 'alpha-testers',
    'release', delegate
    }
    }
    }
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26. Links
    • Gruel Plugin: github.com/jwir3/gruel
    • Slides: andydyer.org
    • Twi2er: @dammitandy
    • Google Plus: +AndrewDyer
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