はやい・やすい・うまい！スタートアップでも使える Retrofit + RxJava で瞬間APIクッキングレシピ

はやい・やすい・うまい！スタートアップでも使える Retrofit + RxJava で瞬間APIクッキングレシピ

Transcript

1. ͸΍͍ɾ΍͍͢ɾ͏·͍ʂ

   ελʔτΞοϓͰ΋࢖͑Δ
   Retrofit + RxJava ͰॠؒAPIΫο
   ΩϯάϨγϐ
   @fushiroyama
   

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2. About Me
   • Fumihiko Shiroyama
   • Android App Developer
   • https://github.com/srym
   

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3. How to implement REST
   Client?
   • HTTP Client
   • Thread Executer
   • JSON Deserializer
   • Integration with RxJava
   

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4. Retrofit
   

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5. Retrofit
   • A type-safe HTTP client for Android and Java
   • http://square.github.io/retrofit/
   • by Square
   

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6. Install
   // Retrofit
   compile "com.squareup.retrofit2:retrofit:${retrofitVersion}"
   compile "com.squareup.retrofit2:adapter-rxjava2:${retrofitVersion}"
   compile "com.squareup.retrofit2:converter-gson:${retrofitVersion}"
   // RxJava
   compile 'io.reactivex.rxjava2:rxandroid:2.0.1'
   compile "io.reactivex.rxjava2:rxjava:2.1.1"
   

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7. Retrofit
   public interface GitHubService {
   @GET("users/{user}/repos")
   Call> listRepos(@Path("user") String user);
   }
   

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8. Retrofit
   Retrofit retrofit = new Retrofit.Builder()
   .baseUrl("https://api.github.com/")
   .build();
   GitHubService service =
   retrofit.create(GitHubService.class);
   

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9. Retrofit
   GitHubService service = retrofit.create(GitHubService.class);
   Call> repos = service.listRepos("srym");
   // synchronous call
   Response> response = repos.execute();
   // asynchronous call
   repos.enqueue( /* callback here */ );
   

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10. Integration with RxJava
    Retrofit retrofit = new Retrofit.Builder()
    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
    .addConverterFactory(GsonConverterFactory.create(gson))
    .baseUrl("https://api.github.com/")
    .build();
    

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11. Change Return Type
    public interface GitHubService {
    @GET("users/{user}/repos")
    Single> listRepos(@Path("user") String user);
    }
    

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12. Subscribe
    Single> repos = service.listRepos("srym")
    repos
    .subscribe(
    list -> doSomethingToList(list),
    throwable -> Timber.d(throwable.getMessage(), throwable),
    () -> Timber.d("complete")
    );
    

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13. Link
    • RxJava+RetrofitͰAPI௨৴पΓΛ࣮૷͢Δ͏͑
    Ͱ࠷௿ݶͷ஌ࣝΛ30෼Ͱ٧ΊࠐΉ
    • http://qiita.com/FumihikoSHIROYAMA/
    items/201536d9b45ef21b6bc7
    

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14. Link
    • RetrofitΛ࢖ͬͨOAuth࠶ೝূΞϓϩʔν
    • http://qiita.com/FumihikoSHIROYAMA/
    items/ac1beaeaa9b4baaed939
    

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15. Link
    • RetrofitΛ࢖ͬͨAPIݺͼग़͠ͰϦΧόϦՄೳ
    ͳHTTPΤϥʔΛͲ͏ѻ͏͔໰୊
    • http://qiita.com/FumihikoSHIROYAMA/
    items/65d52aea1a9f324d347e
    

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16. What's Good about Retrofit +
    Rx
    • Easy to define
    • Easy to compose
    • Easy to test
    

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17. Test
    • MockWebServer
    • TestSubscriber
    

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18. MockWebServer
    • A scriptable web server for testing HTTP
    clients
    • https://github.com/square/okhttp/tree/
    master/mockwebserver
    

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19. MockWebServer
    private final MockWebServer mockWebServer
    = new MockWebServer();
    

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20. MockWebServer
    Dispatcher dispatcher = new Dispatcher() {
    @Override
    public MockResponse dispatch(RecordedRequest request)
    throws InterruptedException {
    return new MockResponse().setResponseCode(404);
    }
    };
    mockWebServer.setDispatcher(dispatcher);
    mockWebServer.start();
    

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21. MockWebServer
    @Override
    public MockResponse dispatch(RecordedRequest request) {
    if (request == null || request.getPath() == null) {
    return new MockResponse().setResponseCode(400);
    }
    if (request.getPath().matches("/users/.+/repos")) {
    return new MockResponse().setBody(
    readJsonFromResources("users_repos.json")
    ).setResponseCode(200);
    }
    return new MockResponse().setResponseCode(404);
    }
    

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22. MockWebServer
    Retrofit retrofit = new Retrofit.Builder()
    .baseUrl(mockWebServer.url(""))
    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
    .addConverterFactory(GsonConverterFactory.create())
    .build();
    GitHubService gitHubService = retrofit.create(GitHubService.class);
    

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23. TestSubscriber
    • A TestSubscriber is a variety of Subscriber
    that you can use for unit testing, to perform
    assertions, inspect received events, or wrap a
    mocked Subscriber.
    • http://reactivex.io/RxJava/javadoc/rx/
    observers/TestSubscriber.html
    

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24. TestSubscriber
    restGitHubDataSource
    .listRepos("srym")
    .test();
    

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25. TestSubscriber
    List repos = restGitHubDataSource.listRepos("srym")
    .test()
    .await()
    .assertNoErrors()
    .assertComplete()
    .values()
    .get(0);
    assertThat(repos).isNotNull();
    

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26. TestSubscriber
    • https://github.com/srym/Architecture
    • https://github.com/srym/Architecture/blob/
    master/app/src/test/java/us/shiroyama/
    android/architecture/infrastructure/
    repository/datasource/remote/
    RestGitHubDataSourceTest.java
    

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27. Easy to compose
    • Rx's Observable is easily & flexibly combined
    • Avoid callback hells
    

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28. Easy to compose
    public class GitHubInfraRepository implements GitHubRepository {
    private final RemoteGitHubDataSource remoteDataSource;
    private final RepoMapper mapper;
    @Inject
    public GitHubInfraRepository(RemoteGitHubDataSource remoteDataSource,
    RepoMapper mapper) {
    this.remoteDataSource = remoteDataSource;
    this.mapper = mapper;
    }
    @Override
    public Single> listRepos(@NonNull String user) {
    return remoteDataSource
    .listRepos(user)
    .map(mapper::convert);
    }
    }
    

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29. Easy to compose
    private final RemoteGitHubDataSource remoteDataSource;
    private final LocalGitHubDataSource localGitHubDataSource;
    private final RepoMapper mapper;
    @Inject
    public GitHubInfraRepository(RemoteGitHubDataSource remoteDataSource,
    LocalGitHubDataSource localGitHubDataSource,
    RepoMapper mapper) {
    this.remoteDataSource = remoteDataSource;
    this.localGitHubDataSource = localGitHubDataSource;
    this.mapper = mapper;
    }
    

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30. Easy to compose
    @Override
    public Single> listRepos(@NonNull String user) {
    return remoteDataSource
    .listRepos(user)
    .map(mapper::convert);
    

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31. Easy to compose
    public Single> listRepos(@NonNull String user) {
    return localGitHubDataSource
    .listRepos(user)
    .onErrorResumeNext(
    remoteDataSource
    .listRepos(user)
    .retry(DEFAULT_RETRY)
    .doOnSuccess(localGitHubDataSource::save)
    )
    .map(mapper::convert);
    

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32. Android Clean Architecture
    • android10/Android-CleanArchitecture
    • https://github.com/android10/Android-
    CleanArchitecture
    • srym/Architecture
    • https://github.com/srym/Architecture
    

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