Issue ReactiveX#235: TimeLimiter as a Reactor operator (ReactiveX#636)

resilience4j-reactor/build.gradle

@@ -1,12 +1,14 @@
 dependencies {
     compileOnly project(':resilience4j-circuitbreaker')
     compileOnly project(':resilience4j-ratelimiter')
+    compileOnly project(':resilience4j-timelimiter')
     compileOnly project(':resilience4j-bulkhead')
     compileOnly project(':resilience4j-retry')
     compileOnly (libraries.reactor)
     testCompile project(':resilience4j-test')
     testCompile project(':resilience4j-circuitbreaker')
     testCompile project(':resilience4j-ratelimiter')
+    testCompile project(':resilience4j-timelimiter')
     testCompile project(':resilience4j-bulkhead')
     testCompile project(':resilience4j-retry')
     testCompile (libraries.reactor)

resilience4j-reactor/src/main/java/io/github/resilience4j/reactor/timelimiter/TimeLimiterOperator.java

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2019 authors
+ *
+ * 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 io.github.resilience4j.reactor.timelimiter;
+
+import io.github.resilience4j.reactor.IllegalPublisherException;
+import io.github.resilience4j.timelimiter.TimeLimiter;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.time.Duration;
+import java.util.function.UnaryOperator;
+
+import org.reactivestreams.Publisher;
+
+/**
+ * A Reactor TimeLimiter operator which wraps a reactive type in a TimeLimiter.
+ *
+ * @param <T> the value type of the upstream and downstream
+ */
+public class TimeLimiterOperator<T> implements UnaryOperator<Publisher<T>> {
+
+    private final TimeLimiter timeLimiter;
+
+    private TimeLimiterOperator(TimeLimiter timeLimiter) {
+        this.timeLimiter = timeLimiter;
+    }
+
+    /**
+     * Creates a timeLimiter.
+     *
+     * @param <T>         the value type of the upstream and downstream
+     * @param timeLimiter the timeLimiter
+     * @return a TimeLimiterOperator
+     */
+    public static <T> TimeLimiterOperator<T> of(TimeLimiter timeLimiter) {
+        return new TimeLimiterOperator<>(timeLimiter);
+    }
+
+    @Override
+    public Publisher<T> apply(Publisher<T> publisher) {
+        if (publisher instanceof Mono) {
+            return withTimeout((Mono<T>) publisher);
+        } else if (publisher instanceof Flux) {
+            return withTimeout((Flux<T>) publisher);
+        } else {
+            throw new IllegalPublisherException(publisher);
+        }
+    }
+
+    private Publisher<T> withTimeout(Mono<T> upstream) {
+        return upstream.timeout(getTimeout())
+                .doOnNext(t -> timeLimiter.onSuccess())
+                .doOnSuccess(t -> timeLimiter.onSuccess())
+                .doOnError(timeLimiter::onError);
+    }
+
+    private Publisher<T> withTimeout(Flux<T> upstream) {
+        return upstream.timeout(getTimeout())
+                .doOnNext(t -> timeLimiter.onSuccess())
+                .doOnComplete(timeLimiter::onSuccess)
+                .doOnError(timeLimiter::onError);
+    }
+
+    private Duration getTimeout() {
+        return timeLimiter.getTimeLimiterConfig().getTimeoutDuration();
+    }
+
+}

resilience4j-reactor/src/test/java/io/github/resilience4j/reactor/timelimiter/TimeLimiterOperatorTest.java

@@ -0,0 +1,173 @@
+/*
+ * Copyright 2019 authors
+ *
+ * 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 io.github.resilience4j.reactor.timelimiter;
+
+import io.github.resilience4j.test.HelloWorldService;
+import io.github.resilience4j.timelimiter.TimeLimiter;
+import io.github.resilience4j.timelimiter.TimeLimiterConfig;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+import java.time.Duration;
+import java.util.concurrent.TimeoutException;
+
+import org.junit.Test;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.BDDMockito.then;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+
+
+public class TimeLimiterOperatorTest {
+
+    private final TimeLimiter timeLimiter = mock(TimeLimiter.class);
+    private final HelloWorldService helloWorldService = mock(HelloWorldService.class);
+
+    @Test
+    public void doNotTimeoutUsingMono() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMinutes(1)));
+        given(helloWorldService.returnHelloWorld())
+                .willReturn("Hello world");
+
+        Mono<?> mono = Mono.fromCallable(helloWorldService::returnHelloWorld)
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(mono)
+                .expectNextCount(1)
+                .verifyComplete();
+        then(timeLimiter).should(times(2))
+                .onSuccess();
+    }
+
+    @Test
+    public void timeoutUsingMono() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMillis(1)));
+
+        Mono<?> mono = Mono.delay(Duration.ofMinutes(1))
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(mono)
+                .expectError(TimeoutException.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(TimeoutException.class));
+    }
+
+    @Test
+    public void timeoutNeverUsingMono() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMillis(1)));
+
+        Mono<?> flux = Mono.never()
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(flux)
+                .expectError(TimeoutException.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(TimeoutException.class));
+    }
+
+    @Test
+    public void otherErrorUsingMono() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMinutes(1)));
+        given(helloWorldService.returnHelloWorld())
+                .willThrow(new Error("BAM!"));
+
+        Mono<?> mono = Mono.fromCallable(helloWorldService::returnHelloWorld)
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(mono)
+                .expectError(Error.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(Error.class));
+    }
+
+    @Test
+    public void doNotTimeoutUsingFlux() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMinutes(1)));
+
+        Flux<?> flux = Flux.interval(Duration.ofMillis(1))
+                .take(2)
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(flux)
+                .expectNextCount(2)
+                .verifyComplete();
+        then(timeLimiter).should(times(3))
+                .onSuccess();
+    }
+
+    @Test
+    public void timeoutUsingFlux() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMillis(1)));
+
+        Flux<?> flux = Flux.interval(Duration.ofSeconds(1))
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(flux)
+                .expectError(TimeoutException.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(TimeoutException.class));
+    }
+
+    @Test
+    public void timeoutNeverUsingFlux() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMillis(1)));
+
+        Flux<?> flux = Flux.never()
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(flux)
+                .expectError(TimeoutException.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(TimeoutException.class));
+    }
+
+    @Test
+    public void otherErrorUsingFlux() {
+        given(timeLimiter.getTimeLimiterConfig())
+                .willReturn(toConfig(Duration.ofMinutes(1)));
+
+        Flux<?> flux = Flux.error(new Error("BAM!"))
+                .compose(TimeLimiterOperator.of(timeLimiter));
+
+        StepVerifier.create(flux)
+                .expectError(Error.class)
+                .verify(Duration.ofMinutes(1));
+        then(timeLimiter).should()
+                .onError(any(Error.class));
+    }
+
+    private TimeLimiterConfig toConfig(Duration timeout) {
+        return TimeLimiterConfig.custom()
+                .timeoutDuration(timeout)
+                .build();
+    }
+}