Tools of the Trade #DCNYC18

With all the great resources and libraries available, building a new mobile app is easier than it’s ever been! But when your users come to expect your product to be as reliable as running water at a global scale, you’ll need to go above and beyond what’s currently available.

Join Ty as he walks down memory lane to cover the history of the Uber app development process. He’ll cover how it grew, the pain points discovered and lessons learned, and the tooling developed and open-sourced to scale to millions of users served by hundreds of contributors across many apps.

Topics covered will include: Buck, Uber’s architecture solution, RIBs, Proper Experimentation, Continuous integration, Code Verification and Static Analysis, and the company processes needed to facilitate a large app.

Transcript

1. Tools of the Trade Ty Smith @tsmith
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17. Topics — Monorepo — Architecture — Libraries and Tools @tsmith
18. MONO REPO @tsmith
19. Pain Points — Dependency Hell — Architectural Silos — Long Build times @tsmith
20. ABI Breaking change @tsmith
21. Many Repos Depedency hell ~/Uber/rider-android/build.gradle dependencies { implementation "com.uber:partner-funnel:1.2.3" implementation "com.uber:single-sign-on:0.7.0" implementation "com.uber:storage:2.1.0" implementation "com.uber:networking:2.3.1" implementation "com.uber:analytics:1.9.0" } ~/Uber/partner-funnel-android/build.gradle dependencies { implementation "com.uber:storage:2.2.0" implementation "com.uber:networking:2.0.0" implementation "com.uber:analytics:1.3.5" } @tsmith
22. Monorepo ~/Uber/Android |-- .git |-- build.gradle |-- apps | |-- rider | |-- driver | |-- eats |-- features | |-- partner-funnel | |-- single-sign-on |-- libraries | |-- storage | |-- networking | |-- analytics @tsmith
23. Monorepo ~/Uber/android/apps/rider/build.gradle dependencies { implementation project(":features:partner-funnel") implementation project(":features:single-sign-on") implementation project(":libraries:storage") implementation project(":libraries:networking") implementation project(":libraries:analytics") } ~/Uber/android/features/partner-funnel/build.gradle dependencies { implementation project(":libraries:storage") implementation project(":libraries:networking") implementation project(":libraries:analytics") } @tsmith
24. Buck @tsmith | buckbuild.com
25. Buck — Output based — Highly Parellelizable — Fast! ! — IDE Integration @tsmith
26. Buck @tsmith
27. OKBuck A gradle plugin that lets developers utilize the Buck build system on a gradle project. @tsmith | github.com/uber/okbuck
28. OKBuck plugins { id 'com.uber.okbuck' version '0.36.0' } @tsmith | github.com/uber/okbuck
29. OKBuck ./gradlew :buckWrapper //List targets ./buckw list //Build Target ./buckw build <target> @tsmith | github.com/uber/okbuck
30. Exopackage @tsmith | buckbuild.com/article/exopackage.html
31. @tsmith
32. Submit Queue @tsmith
33. Architecture @tsmith | Photo by Rich Niewiroski Jr. | CC BY 2.5
34. @tsmith
35. 99.99% reliability of core flows Enable global rollback of core flows to a guaranteed working state @tsmith
36. Support growth for years Narrow and decouple functionality as much as possible @tsmith
37. Rails for Design and Code Guidelines for both architecture and design @tsmith
38. Monitoring is a First-Class Citizen Automatic analytics, logging, debugging, and tracing @tsmith
39. De-risk Experimentation Application framework with plugin API @tsmith
40. Make Magic Performance second to none, graceful degradation on low-end devices and networks @tsmith
41. MVC MVVM VIPER Fat View Controller Fat View Controller View based logic separation Locked view & business tree Locked view & business tree Locked view & business tree @tsmith
42. @tsmith | github.com/uber/ribs
43. RIBs @tsmith | github.com/uber/ribs
44. RIBs @tsmith | github.com/uber/ribs
45. RIBs @tsmith | github.com/uber/ribs
46. RIBs @tsmith | github.com/uber/ribs
47. RIBs @tsmith | github.com/uber/ribs
48. RIBs @tsmith | github.com/uber/ribs
49. RIBs Communication @tsmith | github.com/uber/ribs
50. Libraries @tsmith | Photo by DAVID ILIFF | CC BY-SA 3.0
51. RIBs Intellij Plugin @tsmith | github.com/uber/RIBs/tree/master/android/tooling/rib-intellij-plugin
52. Motif A simple DI API for Android / Java @tsmith | github.com/uber/motif
53. Motif @motif.Scope interface MainScope { ChildScope child(); @motif.Objects class Objects { @Expose Database database() { return new Database(); } } } @tsmith | github.com/uber/motif
54. Motif @motif.Scope interface ChildScope { ChildController controller(); @motif.Objects class Objects { ChildView view() { return new ChildView(); } ChildController controller(Database database, ChildView view) { return new ChildController(database, view); } } } @tsmith | github.com/uber/motif
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56. Crumb An annotation processor for breadcrumbing metadata across compilation boundaries @tsmith | github.com/uber/crumb
57. Crumb @tsmith | github.com/uber/crumb
58. RIBs Plugins class FooPluginFactory : PluginFactory<Intent, FooPlugin> { override fun pluginSwitch() = FOO_PLUGIN_SWITCH override fun isApplicable(intent : Intent) = intent.hasExtra("bar") override fun createNewPlugin(intent : Intent) = FooPlugin(intent) } @tsmith | github.com/uber/crumb
59. RIBs Plugins class BarPluginPoint : PluginPoint<Intent, BarPlugin>() { override val internalPluginFactories = listOf(FooPluginFactory()) } @tsmith | github.com/uber/crumb
60. RIBs Plugins val barPluginPoint = BarPluginPoint(abFramework) val BarPlugin : BarPlugin? = pluginPoint.getPlugin(intent) barPlugin?.doWork() @tsmith | github.com/uber/crumb
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62. Autodispose Automatic binding+disposal of RxJava 2 streams. @tsmith | github.com/uber/autodispose
63. Autodispose observable .doStuff() .as(autoDisposable(this)) .subscribe { ... } @tsmith | github.com/uber/autodispose
64. Autodispose — Maybe — LifecycleScopeProvider — ScopeProvider @tsmith | github.com/uber/autodispose
65. Autodispose Extras! — Kotlin extensions — RX lifecycle extensions — Architecture Components adapter — Plugins — Errorprone checker @tsmith | github.com/uber/autodispose
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67. Workflow Represent a workflow of reactive steps @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
68. Workflow — Step — ActionableItem — Workflow @tsmith
69. Workflow @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
70. Workflow class SingleSignOnWorkflow : HelixRootWorkflow<Step.NoValue, SingleSignOnDeepLink>() { override fun getSteps(rootActionableItem : AppRootActionableItem, deeplink : SingleSignOnDeepLink ) : Step<Step.NoValue, SingleSignOnActionableItem> { return rootActionableItem .onStep(waitUntilSignedIn()) .onStep(GoToMain()) .onStep(showFullScreenRib(singleSignOnRib(deeplink))) } } @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
71. Workflow override fun waitUntilSignedIn() : Step<Step.NoValue, RootSignedInActionableItem> { return Step.from( mutableSession .getAuthStateAsync() .filter { it is AuthState.AuthStateLoggedIn } .take(1) .map { Step.Data.toActionableItem(this) } .singleOrError()) } @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
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75. Artist An artist creates views. Artist is a Gradle plugin that codegens a base set of Android Views. @tsmith | github.com/uber/artist
76. Artist — Stencil: The View Generator — Trait: Reusable functionality @tsmith | github.com/uber/artist
77. Artist class VisibilityTrait : Trait { override fun generateFor( type: Builder, initMethod: MethodSpec.Builder, rClass: ClassName, baseType: String) { listOf("visible", "invisible", "gone") .forEach { type.addMethod(createVisibilityConvenienceMethod(it)) } } private fun createVisibilityConvenienceMethod(type: String): MethodSpec { return MethodSpec.methodBuilder("is${type.capitalize()}") .addModifiers(Modifier.PUBLIC) .returns(TypeName.BOOLEAN) .addStatement("return getVisibility() == \$T.${type.toUpperCase()}", TypeNames.Android.View) .build() } } @tsmith | github.com/uber/artist
78. Artist class SwitchStencil : ViewStencil( extendedType = "android.support.v7.widget.SwitchCompat", constructorCount = 3, defaultAttrRes = "switchStyle", addedTraits = VisibilityTrait::class.java) { override fun name() = "FooSwitch" } @tsmith | github.com/uber/artist
79. Artist public class FooSwitch extends SwitchCompat { // Constructors // protected init method - provided in every stencil public boolean isVisible() { return getVisibility() == View.VISIBLE; } public boolean isGone() { return getVisibility() == View.GONE; } public boolean isInvisible() { return getVisibility() == View.INVISIBLE; } } @tsmith | github.com/uber/artist
80. Stylist A stylist creates cool styles. Stylist is a Gradle plugin that codegens a base set of Android XML themes. @tsmith | github.com/uber/stylist
81. Stylist @AutoService(ThemeStencilProvider::class) class SampleThemeStencilProvider : ThemeStencilProvider { private val textSizes = StyleItemGroup( StyleItem("textSizeSmall", "12dp"), StyleItem("textSizeMedium","16dp"), StyleItem("textSizeLarge", "20dp") ) override fun stencils() = linkedSetOf( ThemeStencil("Theme.Sample.Dark", "Theme.AppCompat"), ThemeStencil("Theme.Sample.Light", "Theme.AppCompat.Light") ) override fun globalStyleItemGroups() = linkedSetOf( textSizes ) } @tsmith | github.com/uber/stylist
82. Stylist <?xml version="1.0" encoding="utf-8" standalone="no"?> <resources> <style name="Theme.Sample.Dark" parent="Theme.AppCompat"> <item name="textSizeSmall">12dp</item> <item name="textSizeMedium">16dp</item> <item name="textSizeLarge">20dp</item> </style> <style name="Theme.Sample.Light" parent="Theme.AppCompat.Light"> <item name="textSizeSmall">12dp</item> <item name="textSizeMedium">16dp</item> <item name="textSizeLarge">20dp</item> </style> </resources> @tsmith | github.com/uber/stylist
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84. Lint class SwitchCompatUsageXmlDetector : ResourceXmlDetector() { override val applicableElements = listOf("android.support.v7.widget.SwitchCompat") override fun visitElement(context:XmlContext, element : Element) : override { context.report( Issue.create("SwitchCompatUsage", "Don't use base view SwitchCompat", "Use Provided FooSwitch", Category.CORRECTNESS, 6, Severity.ERROR, Implementation(XmlUViewUsageDetector::class.java, Scope.RESOURCE_FILE_SCOPE)), element, context.getLocation(element), LINT_ERROR_MESSAGE) } } @tsmith
85. Herald @tsmith | www.phacility.com/phabricator/herald
86. "I call it my billion-dollar mistake. It was the invention of the null reference" - Sir Charles Antony Richard Hoare @tsmith | github.com/uber/NullAway
87. Errorprone public class MyActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); AndroidInjection.inject(this); } } @tsmith | errorprone.info
88. Nullaway A tool to help eliminate NullPointerExceptions in your Java code @tsmith | github.com/uber/NullAway
89. Nullaway static void log(Object x) { System.out.println(x.toString()); } static void foo() { log(null); } @tsmith | github.com/uber/NullAway
90. Nullaway warning: [NullAway] passing @Nullable parameter 'null' where @NonNull is required log(null); ^ @tsmith | github.com/uber/NullAway
91. Nullaway static void log(@Nullable Object x) { if (x != null) { System.out.println(x.toString()); } } @tsmith | github.com/uber/NullAway
92. RAVE Runtime Annotation Validation Engine Ensure models adhere to the set of expectations that are described by their annotations @tsmith | github.com/uber/RAVE
93. RAVE public final class SampleFactory implements ValidatorFactory { @NonNull @Override public BaseValidator generateValidator() { return new SampleFactory_Generated_Validator(); } } @tsmith | github.com/uber/RAVE
94. RAVE @Validated(factory = SampleFactory.class) public class SimpleMatchModel { private String match; private static final String MATCHED = "Matched"; private static final String NOT_MATCHED = "NotMatched"; @StringDef({MATCHED, NOT_MATCHED}) @Retention(RetentionPolicy.SOURCE) @interface StringVals { } @NonNull @StringVals public String getMatch() { return match; } } @tsmith | github.com/uber/RAVE
95. RAVE public void validateMyModel(SimpleModel myModel) { try { Rave.getInstance().validate(myModel); } catch (RaveException e) { // handle rave validation error. } } @tsmith
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97. Thri!y https://github.com/Microsoft/thrifty Wire https://github.com/square/wire @tsmith
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99. Uber Open Source github.com/uber/artist github.com/uber/autodispose github.com/uber/crumb github.com/uber/motif github.com/uber/nullaway github.com/uber/okbuck github.com/uber/rave github.com/uber/ribs github.com/uber/stylist @tsmith
100. Resources Architecture rewrite - t.uber.com/ribs-1 Dependency hierarchies - t.uber.com/ribs-2 RIBs - t.uber.com/ribs-3 Plugins - t.uber.com/ribs-4 Monorepo - t.uber.com/monorepo-1 @tsmith
101. Tools of the Trade Ty Smith @tsmith