具有回滚异常策略的 Mule ESB 简单 http 请求

Question

我正在尝试执行以下操作：

1. 调用不存在的api
2. 尝试重新发送原始请求 5 次
3. 发送用完时打印消息

我有以下流程：

<http:request-config name="HTTP_Request_Configuration" host="localhost" port="80" doc:name="HTTP Request Configuration"/>
<http:listener-config name="HTTP_Listener_Configuration" host="0.0.0.0" port="8081" doc:name="HTTP Listener Configuration"/>
<flow name="exceptionTestFlow">
    <http:listener config-ref="HTTP_Listener_Configuration" path="/" doc:name="HTTP"/>
    <flow-ref name="exceptionTestSubFlow" doc:name="Flow Reference"/>
</flow>
<flow name="exceptionTestSubFlow">
    <http:request config-ref="HTTP_Request_Configuration" path="/hello/" method="GET" doc:name="HTTP"/>
    <rollback-exception-strategy doc:name="Rollback Exception Strategy" maxRedeliveryAttempts="5">
        <logger message="redelivering..." level="INFO" doc:name="Logger"/>
        <on-redelivery-attempts-exceeded>
            <logger message="redelivery exhausted" level="INFO" doc:name="Logger"/>
        </on-redelivery-attempts-exceeded>
    </rollback-exception-strategy>
</flow>

但我得到以下输出：

ERROR 2015-03-02 14:15:34,820 [[exceptiontest].HTTP_Listener_Configuration.worker.01] org.mule.exception.RollbackMessagingExceptionStrategy:

---

Message : Response code 404 mapped as failure. Message payload is of type: BufferInputStream

Code : MULE_ERROR--2

Exception stack is: 1. Response code 404 mapped as failure. Message payload is of type: BufferInputStream (org.mule.module.http.internal.request.ResponseValidatorException)

org.mule.module.http.internal.request.SuccessStatusCodeValidator:37 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/module/http/internal/request/ResponseValidatorException.html)

Root Exception stack trace: org.mule.module.http.internal.request.ResponseValidatorException: Response code 404 mapped as failure. Message payload is of type: BufferInputStream at org.mule.module.http.internal.request.SuccessStatusCodeValidator.validate(SuccessStatusCodeValidator.java:37) at org.mule.module.http.internal.request.DefaultHttpRequester.innerProcess(DefaultHttpRequester.java:202) at org.mule.module.http.internal.request.DefaultHttpRequester.process(DefaultHttpRequester.java:166) + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)

---

INFO 2015-03-02 14:15:34,820 [[exceptiontest].HTTP_Listener_Configuration.worker.01] org.mule.api.processor.LoggerMessageProcessor: redelivering... ERROR 2015-03-02 14:15:34,822 [[exceptiontest].HTTP_Listener_Configuration.worker.01] org.mule.exception.DefaultMessagingExceptionStrategy:

---

Message : Response code 404 mapped as failure. Message payload is of type: BufferInputStream

Code : MULE_ERROR--2

Exception stack is: 1. Response code 404 mapped as failure. Message payload is of type: BufferInputStream (org.mule.module.http.internal.request.ResponseValidatorException)

org.mule.module.http.internal.request.SuccessStatusCodeValidator:37 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/module/http/internal/request/ResponseValidatorException.html)

Root Exception stack trace: org.mule.module.http.internal.request.ResponseValidatorException: Response code 404 mapped as failure. Message payload is of type: BufferInputStream at org.mule.module.http.internal.request.SuccessStatusCodeValidator.validate(SuccessStatusCodeValidator.java:37) at org.mule.module.http.internal.request.DefaultHttpRequester.innerProcess(DefaultHttpRequester.java:202) at org.mule.module.http.internal.request.DefaultHttpRequester.process(DefaultHttpRequester.java:166) + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)

---

我预计它会尝试重新投递 5 次，但它似乎不起作用。我做错了什么吗？非常感谢。

ps 我试过将子流程包装在事务块中，但这也不起作用

Answer 1

我会改用 Until Successful Scope since I believe HTTP does not support redelivery (see the doc for Rollback Exception Strategy).

Answer 2

由于 HTTP 调用是无状态对象，定义回滚似乎不是一个好的选择。 在 until-successful 范围内定义您所需的失败条件，相应的重试次数似乎是实现您的要求的好选择。

供参考