/**
* Copyright 2014 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package rx.internal.operators;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.fail;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import java.util.Arrays;
import java.util.concurrent.atomic.AtomicReference;
import org.junit.Test;
import org.mockito.Mockito;
import rx.Observable;
import rx.Observable.Operator;
import rx.Observer;
import rx.Subscriber;
import rx.Subscription;
import rx.functions.Func1;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
public class OperatorOnErrorResumeNextViaFunctionTest {
@Test
public void testResumeNextWithSynchronousExecution() {
final AtomicReference<Throwable> receivedException = new AtomicReference<Throwable>();
Observable<String> w = Observable.create(new Observable.OnSubscribe<String>() {
@Override
public void call(Subscriber<? super String> observer) {
observer.onNext("one");
observer.onError(new Throwable("injected failure"));
observer.onNext("two");
observer.onNext("three");
}
});
Func1<Throwable, Observable<String>> resume = new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
receivedException.set(t1);
return Observable.just("twoResume", "threeResume");
}
};
Observable<String> observable = w.onErrorResumeNext(resume);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
observable.subscribe(observer);
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
verify(observer, times(1)).onNext("one");
verify(observer, Mockito.never()).onNext("two");
verify(observer, Mockito.never()).onNext("three");
verify(observer, times(1)).onNext("twoResume");
verify(observer, times(1)).onNext("threeResume");
assertNotNull(receivedException.get());
}
@Test
public void testResumeNextWithAsyncExecution() {
final AtomicReference<Throwable> receivedException = new AtomicReference<Throwable>();
Subscription s = mock(Subscription.class);
TestObservable w = new TestObservable(s, "one");
Func1<Throwable, Observable<String>> resume = new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
receivedException.set(t1);
return Observable.just("twoResume", "threeResume");
}
};
Observable<String> observable = Observable.create(w).onErrorResumeNext(resume);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
observable.subscribe(observer);
try {
w.t.join();
} catch (InterruptedException e) {
fail(e.getMessage());
}
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
verify(observer, times(1)).onNext("one");
verify(observer, Mockito.never()).onNext("two");
verify(observer, Mockito.never()).onNext("three");
verify(observer, times(1)).onNext("twoResume");
verify(observer, times(1)).onNext("threeResume");
assertNotNull(receivedException.get());
}
/**
* Test that when a function throws an exception this is propagated through onError
*/
@Test
public void testFunctionThrowsError() {
Subscription s = mock(Subscription.class);
TestObservable w = new TestObservable(s, "one");
Func1<Throwable, Observable<String>> resume = new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
throw new RuntimeException("exception from function");
}
};
Observable<String> observable = Observable.create(w).onErrorResumeNext(resume);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
observable.subscribe(observer);
try {
w.t.join();
} catch (InterruptedException e) {
fail(e.getMessage());
}
// we should get the "one" value before the error
verify(observer, times(1)).onNext("one");
// we should have received an onError call on the Observer since the resume function threw an exception
verify(observer, times(1)).onError(any(Throwable.class));
verify(observer, times(0)).onCompleted();
}
/**
* Test that we receive the onError if an exception is thrown from an operator that
* does not have manual try/catch handling like map does.
*/
@Test
public void testOnErrorResumeReceivesErrorFromPreviousNonProtectedOperator() {
TestSubscriber<String> ts = new TestSubscriber<String>();
Observable.just(1).lift(new Operator<String, Integer>() {
@Override
public Subscriber<? super Integer> call(Subscriber<? super String> t1) {
throw new RuntimeException("failed");
}
}).onErrorResumeNext(new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
if (t1.getMessage().equals("failed")) {
return Observable.just("success");
} else {
return Observable.error(t1);
}
}
}).subscribe(ts);
ts.assertTerminalEvent();
System.out.println(ts.getOnNextEvents());
ts.assertReceivedOnNext(Arrays.asList("success"));
}
/**
* Test that we receive the onError if an exception is thrown from an operator that
* does not have manual try/catch handling like map does.
*/
@Test
public void testOnErrorResumeReceivesErrorFromPreviousNonProtectedOperatorOnNext() {
TestSubscriber<String> ts = new TestSubscriber<String>();
Observable.just(1).lift(new Operator<String, Integer>() {
@Override
public Subscriber<? super Integer> call(Subscriber<? super String> t1) {
return new Subscriber<Integer>() {
@Override
public void onCompleted() {
throw new RuntimeException("failed");
}
@Override
public void onError(Throwable e) {
throw new RuntimeException("failed");
}
@Override
public void onNext(Integer t) {
throw new RuntimeException("failed");
}
};
}
}).onErrorResumeNext(new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
if (t1.getMessage().equals("failed")) {
return Observable.just("success");
} else {
return Observable.error(t1);
}
}
}).subscribe(ts);
ts.assertTerminalEvent();
System.out.println(ts.getOnNextEvents());
ts.assertReceivedOnNext(Arrays.asList("success"));
}
@Test
public void testMapResumeAsyncNext() {
// Trigger multiple failures
Observable<String> w = Observable.just("one", "fail", "two", "three", "fail");
// Introduce map function that fails intermittently (Map does not prevent this when the observer is a
// rx.operator incl onErrorResumeNextViaObservable)
w = w.map(new Func1<String, String>() {
@Override
public String call(String s) {
if ("fail".equals(s))
throw new RuntimeException("Forced Failure");
System.out.println("BadMapper:" + s);
return s;
}
});
Observable<String> observable = w.onErrorResumeNext(new Func1<Throwable, Observable<String>>() {
@Override
public Observable<String> call(Throwable t1) {
return Observable.just("twoResume", "threeResume").subscribeOn(Schedulers.computation());
}
});
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
TestSubscriber<String> ts = new TestSubscriber<String>(observer);
observable.subscribe(ts);
ts.awaitTerminalEvent();
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
verify(observer, times(1)).onNext("one");
verify(observer, Mockito.never()).onNext("two");
verify(observer, Mockito.never()).onNext("three");
verify(observer, times(1)).onNext("twoResume");
verify(observer, times(1)).onNext("threeResume");
}
private static class TestObservable implements Observable.OnSubscribe<String> {
final Subscription s;
final String[] values;
Thread t = null;
public TestObservable(Subscription s, String... values) {
this.s = s;
this.values = values;
}
@Override
public void call(final Subscriber<? super String> observer) {
System.out.println("TestObservable subscribed to ...");
observer.add(s);
t = new Thread(new Runnable() {
@Override
public void run() {
try {
System.out.println("running TestObservable thread");
for (String s : values) {
System.out.println("TestObservable onNext: " + s);
observer.onNext(s);
}
throw new RuntimeException("Forced Failure");
} catch (Throwable e) {
observer.onError(e);
}
}
});
System.out.println("starting TestObservable thread");
t.start();
System.out.println("done starting TestObservable thread");
}
}
@Test
public void testBackpressure() {
TestSubscriber<Integer> ts = new TestSubscriber<Integer>();
Observable.range(0, 100000)
.onErrorResumeNext(new Func1<Throwable, Observable<Integer>>() {
@Override
public Observable<Integer> call(Throwable t1) {
return Observable.just(1);
}
})
.observeOn(Schedulers.computation())
.map(new Func1<Integer, Integer>() {
int c = 0;
@Override
public Integer call(Integer t1) {
if (c++ <= 1) {
// slow
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
return t1;
}
})
.subscribe(ts);
ts.awaitTerminalEvent();
ts.assertNoErrors();
}
}