Touching motif - DI library for Android and Java applications

I have talked about uber/motif library which provides simple API for dependency injection at potatotips#54.

uber/motif: A simple DI API for Android / Java
https://github.com/uber/motif

Transcript

1. uber/motif @shaunkawano
2. •DI library - simple API optimized for nested scopes •Generates Dagger code for actual DI •Under heavily development uber/motif
4. Usage
5. @motif.Scope interface AppScope { @motif.Objects abstract class Objects { fun okHttpClient(): OkHttpClient = 
 OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl("") .addCallAdapterFactory(RxJava2CallAdapterFactory.createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
6. @motif.Scope interface AppScope { @motif.Objects abstract class Objects { fun okHttpClient(): OkHttpClient = 
 OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl("") .addCallAdapterFactory(RxJava2CallAdapterFactory.createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
7. @motif.Scope interface AppScope { @motif.Objects abstract class Objects { fun okHttpClient(): OkHttpClient = 
 OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl("") .addCallAdapterFactory(RxJava2CallAdapterFactory.createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
8. @motif.Scope interface AppScope { @motif.Objects abstract class Objects { fun okHttpClient(): OkHttpClient = 
 OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl("") .addCallAdapterFactory(RxJava2CallAdapterFactory.createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
11. public class AppScopeImpl implements AppScope { private final Component component; public AppScopeImpl(Dependencies dependencies) { this.component = DaggerAppScopeImpl_Component.builder() .dependencies(dependencies) .module(new Module()) .build(); } public AppScopeImpl() { this(new Dependencies() {}); } public interface Dependencies { } @DaggerScope @dagger.Component( dependencies = Dependencies.class, modules = Module.class ) interface Component { } private static class Objects extends AppScope.Objects { } …
12. @dagger.Module class Module { private final AppScope.Objects objects = new Objects(); @Provides AppScope appScope() { return AppScopeImpl.this; } @Provides @DaggerScope OkHttpClient okHttpClient() { return objects.okHttpClient(); } @Provides @DaggerScope Retrofit retrofit(OkHttpClient okHttpClient) { return objects.retrofit(okHttpClient); } @Provides @DaggerScope Service service(Retrofit retrofit) { return objects.service(retrofit); } … }
14. public final class AppScopeImpl_Module_ApiFactory implements Factory<Api> { private final AppScopeImpl.Module module; private final Provider<Service> serviceProvider; public AppScopeImpl_Module_ApiFactory( AppScopeImpl.Module module, Provider<Service> serviceProvider) { this.module = module; this.serviceProvider = serviceProvider; } @Override public Api get() { return provideInstance(module, serviceProvider); } public static Api provideInstance(AppScopeImpl.Module module, Provider<Service> serviceProvider) { return proxyApi(module, serviceProvider.get()); } … public static Api proxyApi(AppScopeImpl.Module instance, Service service) { return Preconditions.checkNotNull( instance.api(service), "Cannot return null from a non-@Nullable @Provides method"); } }
15. It generates code similar to or the same as what dagger generates
16. dagger & motif?
17. # of concepts
18. @RootComponent.Scope @Component(modules = RootComponent.Module.class) public interface RootComponent { RootController controller(); LoggedInComponent.Builder loggedIn(); @dagger.Component.Builder interface Builder { @BindsInstance Builder viewGroup(@Root ViewGroup parent); RootComponent build(); } @dagger.Module abstract class Module { @Scope @Provides static RootView view(@Root ViewGroup parent) { return RootView.create(parent); } } @javax.inject.Scope @interface Scope {} @Qualifier @interface Root {} }
19. @RootComponent.Scope @Component(modules = RootComponent.Module.class) public interface RootComponent { RootController controller(); LoggedInComponent.Builder loggedIn(); @dagger.Component.Builder interface Builder { @BindsInstance Builder viewGroup(@Root ViewGroup parent); RootComponent build(); } @dagger.Module abstract class Module { @Scope @Provides static RootView view(@Root ViewGroup parent) { return RootView.create(parent); } } @javax.inject.Scope @interface Scope {} @Qualifier @interface Root {} } •@Scope •@Component / @Subcomponent •@Component.Buidler / @Subcomponent.Builder •@Qualifier •@BindsInstance •@Module •@Provides •abstract @Modules •static @Provides •Component provision method •Component factory method •Constructor injection
20. @Scope public interface RootScope { RootController controller(); LoggedInScope loggedIn(ViewGroup parentViewGroup); @motif.Objects abstract class Objects { abstract RootController controller(); RootView view(ViewGroup viewGroup) { return RootView.create(viewGroup); } } }
21. @Scope public interface RootScope { RootController controller(); LoggedInScope loggedIn(ViewGroup parentViewGroup); @motif.Objects abstract class Objects { abstract RootController controller(); RootView view(ViewGroup viewGroup) { return RootView.create(viewGroup); } } } •@motif.Scope •@motif.Objects •Access method •Child method •Factory method (Basic) •Factory method (Constructor Injected)
22. •dagger •Fully customizable •Required to understand its concepts •Code readability concern •motif •Less customizable •Less concepts •More readable Philosophy
23. @Expose
24. @motif.Scope interface ChildScope { @motif.Objects open class Objects { fun childService(retrofit: Retrofit): ChildService = retrofit.create(ChildService::class.java) fun childApi(childService: ChildService): ChildApi = ChildApiClient(childService) } }
25. @motif.Scope interface ChildScope { @motif.Objects open class Objects { fun childService(retrofit: Retrofit): ChildService = retrofit.create(ChildService::class.java) fun childApi(childService: ChildService): ChildApi = ChildApiClient(childService) } }
26. @motif.Scope interface AppScope { fun childScope(): ChildScope @motif.Objects open class Objects { fun okHttpClient(): OkHttpClient = OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl(“") .addCallAdapterFactory(RxJava2CallAdapterFactory .createAsync()).build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
27. @motif.Scope interface AppScope { fun childScope(): ChildScope @motif.Objects open class Objects { fun okHttpClient(): OkHttpClient = OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl(“") .addCallAdapterFactory(RxJava2CallAdapterFactory .createAsync()).build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
29. @Expose
30. @motif.Scope interface AppScope { fun childScope(): ChildScope @motif.Objects open class Objects { fun okHttpClient(): OkHttpClient = OkHttpClient.Builder().build() fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl(“") .addCallAdapterFactory(RxJava2CallAdapterFactory .createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
31. @motif.Scope interface AppScope { fun childScope(): ChildScope @motif.Objects open class Objects { fun okHttpClient(): OkHttpClient = OkHttpClient.Builder().build() @Expose fun retrofit(okHttpClient: OkHttpClient): Retrofit = Retrofit.Builder().client(okHttpClient).baseUrl("") .addCallAdapterFactory(RxJava2CallAdapterFactory .createAsync()) .build() fun service(retrofit: Retrofit): Service = retrofit.create(Service::class.java) fun api(service: Service): Api = ApiClient(service) } }
32. Summary
33. •DI library •Clearly different from Dagger •Under heavily development •Read and understand its philosophy before choosing to use it or not uber/motif
34. Uber/Motif @shaunkawano Thank you!