8

我正在尝试使用@Retryable调用 REST 模板的方法。如果由于通信错误而返回错误，我想重试，否则我只想在调用中抛出异常。

当 ApiException 发生时，而不是被 @Retryable 抛出和忽略，我收到一个ExhaustedRetryException关于没有找到足够的“可恢复”（即@Recover方法）的抱怨。

我想我会看看是否存在可恢复的方法是否可以让它快乐并仍然按预期执行。没那么多。它没有抛出异常，而是调用了可恢复方法。

@Retryable(exclude = ApiException include = ConnectionException, maxAttempts = 5, backoff = @Backoff(multiplier = 2.5d, maxDelay = 1000000L, delay = 150000L))
Object call(String domainUri, ParameterizedTypeReference type, Optional<?> domain = Optional.empty(), HttpMethod httpMethod = HttpMethod.POST) throws RestClientException {

    RequestEntity request = apiRequestFactory.createRequest(domainUri, domain, httpMethod)
    log.info "************************** Request Entity **************************"
    log.info "${request.toString()}"
    ResponseEntity response

    try {

        response = restTemplate.exchange(request, type)
        log.info "************************** Response Entity **************************"
        log.info "${response.toString()}"

    } catch (HttpStatusCodeException | HttpMessageNotWritableException httpException) {

        String errorMessage
        String exceptionClass = httpException.class.name.concat("-")
        if(httpException instanceof HttpStatusCodeException) {

            log.info "************************** API Error **************************"
            log.error("API responded with errors: ${httpException.responseBodyAsString}")
            ApiError apiError = buildErrorResponse(httpException.responseBodyAsString)
            errorMessage = extractErrorMessage(apiError)

            if(isHttpCommunicationError(httpException.getStatusCode().value())) {
                throw new ConnectionException(exceptionClass.concat(errorMessage))
            }
        }

        errorMessage = StringUtils.isBlank(errorMessage) ? exceptionClass.concat(httpException.message) : exceptionClass.concat(errorMessage)
        throw new ApiException(httpMethod, domainUri, errorMessage)

    }

    if (type.type == ResponseEntity) {
        response
    }
    else response.body

}

@Recover
Object connectionException(ConnectionException connEx) {
    log.error("Retry failure - communicaiton error")
    throw new ConnectionException(connEx.class.name + " - " + connEx.message)
}

任何见解将不胜感激。是错误还是操作员错误？这是使用 Spring Boot 1.3.6 和 Spring-Retry 1.1.3。

4

1 回答 1

7

您的包含/排除语法看起来很糟糕 - 甚至无法编译。

我刚刚写了一个快速测试，如果你有零个@Recover方法，它会完全按照预期工作......

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.retry.annotation.EnableRetry;
import org.springframework.retry.annotation.Retryable;

@SpringBootApplication
@EnableRetry
public class So38601998Application {

    public static void main(String[] args) {
        ConfigurableApplicationContext context = SpringApplication.run(So38601998Application.class, args);
        Foo bean = context.getBean(Foo.class);
        try {
            bean.out("foo");
        }
        catch (Exception e) {
            System.out.println(e);
        }
        try {
            bean.out("bar");
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }


    @Bean
    public Foo foo() {
        return new Foo();
    }

    public static class Foo {

        @Retryable(include = IllegalArgumentException.class, exclude = IllegalStateException.class,
                maxAttempts = 5)
        public void out(String foo) {
            System.out.println(foo);
            if (foo.equals("foo")) {
                throw new IllegalArgumentException();
            }
            else {
                throw new IllegalStateException();
            }
        }

    }

}

结果：

foo
foo
foo
foo
foo
java.lang.IllegalArgumentException
bar
java.lang.IllegalStateException

如果你只是添加

@Recover
public void connectionException(IllegalArgumentException e) {
    System.out.println("Retry failure");
}

你得到

foo
foo
foo
foo
foo
Retry failure
bar
org.springframework.retry.ExhaustedRetryException: Cannot locate recovery method; nested exception is java.lang.IllegalStateException

所以你需要一个包罗万象的@Recover方法......

@Recover
public void connectionException(Exception e) throws Exception {
    System.out.println("Retry failure");
    throw e;
}

结果：

foo
foo
foo
foo
foo
Retry failure
bar
Retry failure
java.lang.IllegalStateException
于 2016-07-27T13:13:07.740 回答