android - 改造 API 调用收到 "HTTP FAILED: java.io.IOException: Canceled"

Question

无法弄清楚为什么会发生这种情况。我的调用不会触发任何一个 rx 回调(onCompleted()、onError()、onNext())。我唯一收到的是这个 okhttp 输出:

D/OkHttp: --> GET https://api.privatbank.ua/p24api/exchange_rates?json=true&date=20.11.2016 http/1.1
D/OkHttp: --> END GET
D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled

改造模块:

@Module
public class RestModule {

    @Provides
    @Singleton
    public HttpLoggingInterceptor providesHttpLogginInterceptor() {
        return new HttpLoggingInterceptor().setLevel(HttpLoggingInterceptor.Level.BODY);
    }

    @Provides
    @Singleton
    public OkHttpClient providesOkHttpClient(@NonNull HttpLoggingInterceptor loggingInterceptor) {
        return new OkHttpClient.Builder()
            .addInterceptor(loggingInterceptor)
            .connectTimeout(ConstantsManager.CONNECTION_TIME_OUT, TimeUnit.SECONDS)
            .readTimeout(ConstantsManager.READ_TIME_OUT, TimeUnit.SECONDS)
            .build();
    }

    @Provides
    @Singleton
    public Gson providesGson() {
        return new GsonBuilder().create();
    }

    @Provides
    @Singleton
    public Retrofit providesRetrofit(@NonNull OkHttpClient okHttpClient, @NonNull Gson gson) {
        return new Retrofit.Builder()
            .baseUrl(ConstantsManager.BASE_URL)
            .client(okHttpClient)
            .addConverterFactory(SimpleXmlConverterFactory.create())
            .addConverterFactory(GsonConverterFactory.create(gson))
            .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
            .build();
    }

    @Provides
    @Singleton
    public PrivatbankApi providesPrivatbankApi(@NonNull Retrofit retrofit) {
        return retrofit.create(PrivatbankApi.class);
    }
}

API接口(interface):

public interface PrivatbankApi {

    @GET
    Observable<CurrentRates> loadCurrentRates(@NonNull @Url String url);

    @GET("exchange_rates")
    Observable<DateRates> loadDateRates(@NonNull @Query("json") Boolean json, @NonNull @Query("date") String date);

}

订阅:

subscription = dataManager.loadDateRates(date)
                .subscribeOn(Schedulers.io())
                .doAfterTerminate(() -> {
                })
                .subscribe(dateRates -> {
                    // My code here...
                }, throwable -> {
                    Timber.e(throwable, "Error while loading data occurred!");
                });

顺便说一句，两个调用都得到相同的错误:

D/OkHttp: --> GET https://privat24.privatbank.ua/p24/accountorder?oper=prp&PUREXML&apicour&country=ua http/1.1
D/OkHttp: --> END GET
D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled
D/OkHttp: --> GET https://api.privatbank.ua/p24api/exchange_rates?json=true&date=20.11.2016 http/1.1
D/OkHttp: --> END GET
D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled

Answer 1

如果用户取消请求，则会引发该异常。使用 RxJavaCallAdapterFactory 时，如果在调用完成之前取消订阅，就会发生这种情况。所以我猜在你打电话后的某个时候，你会做 subscription.unsubscribe() 这会取消底层的请求。