io.github.resilience4j.retry.configure.RetryAspect Maven / Gradle / Ivy
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/*
* Copyright 2019 Mahmoud Romeh
*
* 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.retry.configure;
import io.github.resilience4j.core.lang.Nullable;
import io.github.resilience4j.fallback.FallbackDecorators;
import io.github.resilience4j.fallback.FallbackMethod;
import io.github.resilience4j.retry.RetryRegistry;
import io.github.resilience4j.retry.annotation.Retry;
import io.github.resilience4j.spelresolver.SpelResolver;
import io.github.resilience4j.utils.AnnotationExtractor;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.Ordered;
import org.springframework.util.StringUtils;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.List;
import java.util.concurrent.*;
/**
* This Spring AOP aspect intercepts all methods which are annotated with a {@link Retry}
* annotation. The aspect will handle methods that return a RxJava2 reactive type, Spring Reactor
* reactive type, CompletionStage type, or value type.
*
* The RetryRegistry is used to retrieve an instance of a Retry for a specific name.
*
* Given a method like this:
*
* {@literal @}Retry(name = "myService")
* public String fancyName(String name) {
* return "Sir Captain " + name;
* }
*
* each time the {@code #fancyName(String)} method is invoked, the method's execution will pass
* through a a {@link io.github.resilience4j.retry.Retry} according to the given config.
*
* The fallbackMethod parameter signature must match either:
*
* 1) The method parameter signature on the annotated method or 2) The method parameter signature
* with a matching exception type as the last parameter on the annotated method
*/
@Aspect
public class RetryAspect implements Ordered, AutoCloseable {
private static final Logger logger = LoggerFactory.getLogger(RetryAspect.class);
private final static ScheduledExecutorService retryExecutorService = Executors
.newScheduledThreadPool(Runtime.getRuntime().availableProcessors());
private final RetryConfigurationProperties retryConfigurationProperties;
private final RetryRegistry retryRegistry;
private final @Nullable
List retryAspectExtList;
private final FallbackDecorators fallbackDecorators;
private final SpelResolver spelResolver;
/**
* @param retryConfigurationProperties spring retry config properties
* @param retryRegistry retry definition registry
* @param retryAspectExtList a list of retry aspect extensions
* @param fallbackDecorators the fallback decorators
* @param spelResolver spel expression parser
*/
public RetryAspect(RetryConfigurationProperties retryConfigurationProperties,
RetryRegistry retryRegistry,
@Autowired(required = false) List retryAspectExtList,
FallbackDecorators fallbackDecorators,
SpelResolver spelResolver) {
this.retryConfigurationProperties = retryConfigurationProperties;
this.retryRegistry = retryRegistry;
this.retryAspectExtList = retryAspectExtList;
this.fallbackDecorators = fallbackDecorators;
this.spelResolver = spelResolver;
}
@Pointcut(value = "@within(retry) || @annotation(retry)", argNames = "retry")
public void matchAnnotatedClassOrMethod(Retry retry) {
}
@Around(value = "matchAnnotatedClassOrMethod(retryAnnotation)", argNames = "proceedingJoinPoint, retryAnnotation")
public Object retryAroundAdvice(ProceedingJoinPoint proceedingJoinPoint,
@Nullable Retry retryAnnotation) throws Throwable {
Method method = ((MethodSignature) proceedingJoinPoint.getSignature()).getMethod();
String methodName = method.getDeclaringClass().getName() + "#" + method.getName();
if (retryAnnotation == null) {
retryAnnotation = getRetryAnnotation(proceedingJoinPoint);
}
if (retryAnnotation == null) { //because annotations wasn't found
return proceedingJoinPoint.proceed();
}
String backend = spelResolver.resolve(method, proceedingJoinPoint.getArgs(), retryAnnotation.name());
io.github.resilience4j.retry.Retry retry = getOrCreateRetry(methodName, backend);
Class returnType = method.getReturnType();
String fallbackMethodValue = spelResolver.resolve(method, proceedingJoinPoint.getArgs(), retryAnnotation.fallbackMethod());
if (StringUtils.isEmpty(fallbackMethodValue)) {
return proceed(proceedingJoinPoint, methodName, retry, returnType);
}
FallbackMethod fallbackMethod = FallbackMethod
.create(fallbackMethodValue, method, proceedingJoinPoint.getArgs(),
proceedingJoinPoint.getTarget());
return fallbackDecorators.decorate(fallbackMethod,
() -> proceed(proceedingJoinPoint, methodName, retry, returnType)).apply();
}
private Object proceed(ProceedingJoinPoint proceedingJoinPoint, String methodName,
io.github.resilience4j.retry.Retry retry, Class returnType) throws Throwable {
if (CompletionStage.class.isAssignableFrom(returnType)) {
return handleJoinPointCompletableFuture(proceedingJoinPoint, retry);
}
if (retryAspectExtList != null && !retryAspectExtList.isEmpty()) {
for (RetryAspectExt retryAspectExt : retryAspectExtList) {
if (retryAspectExt.canHandleReturnType(returnType)) {
return retryAspectExt.handle(proceedingJoinPoint, retry, methodName);
}
}
}
return handleDefaultJoinPoint(proceedingJoinPoint, retry);
}
/**
* @param methodName the retry method name
* @param backend the retry backend name
* @return the configured retry
*/
private io.github.resilience4j.retry.Retry getOrCreateRetry(String methodName, String backend) {
io.github.resilience4j.retry.Retry retry = retryRegistry.retry(backend);
if (logger.isDebugEnabled()) {
logger.debug(
"Created or retrieved retry '{}' with max attempts rate '{}' for method: '{}'",
backend, retry.getRetryConfig().getResultPredicate(), methodName);
}
return retry;
}
/**
* @param proceedingJoinPoint the aspect joint point
* @return the retry annotation
*/
@Nullable
private Retry getRetryAnnotation(ProceedingJoinPoint proceedingJoinPoint) {
if (proceedingJoinPoint.getTarget() instanceof Proxy) {
logger.debug("The retry annotation is kept on a interface which is acting as a proxy");
return AnnotationExtractor
.extractAnnotationFromProxy(proceedingJoinPoint.getTarget(), Retry.class);
} else {
return AnnotationExtractor
.extract(proceedingJoinPoint.getTarget().getClass(), Retry.class);
}
}
/**
* @param proceedingJoinPoint the AOP logic joint point
* @param retry the configured sync retry
* @return the result object if any
* @throws Throwable
*/
private Object handleDefaultJoinPoint(ProceedingJoinPoint proceedingJoinPoint,
io.github.resilience4j.retry.Retry retry) throws Throwable {
return retry.executeCheckedSupplier(proceedingJoinPoint::proceed);
}
/**
* @param proceedingJoinPoint the AOP logic joint point
* @param retry the configured async retry
* @return the result object if any
*/
@SuppressWarnings("unchecked")
private Object handleJoinPointCompletableFuture(ProceedingJoinPoint proceedingJoinPoint,
io.github.resilience4j.retry.Retry retry) {
return retry.executeCompletionStage(retryExecutorService, () -> {
try {
return (CompletionStage