由于 Mule 中返回的消息类型不同，返回类型不匹配错误

Question

我有一个 Mule 工作流，它可以接收响应消息或业务错误消息作为转换消息连接器的输入。

当它从转换消息连接器移动到对象到字符串时，它会遇到此错误：

ERROR 2016-10-07 18:08:40,187 [[userprocess].userprocess-httpListenerConfig.worker.01] org.mule.exception.DefaultMessagingExceptionStrategy: 
********************************************************************************
Message               : Exception while executing: 
    }) when ((payload[0].userResponse != null and payload[0].userResponse.category == "SUCCESS")) and
                         ^
Type mismatch
     found :name, :string
  required :name, :object
Type                  : com.mulesoft.weave.mule.exception.WeaveExecutionException
Code                  : MULE_ERROR--2
********************************************************************************
Exception stack is:
1. Type mismatch
     found :name, :string
  required :name, :object (com.mulesoft.weave.engine.ast.dynamic.DynamicDispatchException)
  com.mulesoft.weave.engine.ast.dynamic.DynamicDispatchNode:65 (null)
2. Exception while executing: 
    }) when ((payload[0].userResponse != null and payload[0].userResponse.category == "SUCCESS")) and
                         ^
Type mismatch
     found :name, :string
  required :name, :object (com.mulesoft.weave.mule.exception.WeaveExecutionException)
  com.mulesoft.weave.mule.WeaveMessageProcessor$WeaveOutputHandler:166 (null)
********************************************************************************
Root Exception stack trace:
com.mulesoft.weave.engine.ast.dynamic.DynamicDispatchException: Type mismatch
     found :name, :string
  required :name, :object

我认为这是因为当消息被转换消息处理时，它会根据不同的字段执行逻辑，所以我需要做的是在返回业务错误消息时忽略任何响应消息逻辑，反之亦然。

我该怎么做？

Dataweave 代码（JSON 到 XML）：

%dw 1.0
%output application/xml
---
{
    (Data: {
        userId: flowVars.queryParams.userId,
        Message: "User created successfully"
    }) when (payload[0].userResponse.category == "SUCCESS") and
            (payload[1].userResponse.category == "SUCCESS"),            

    (Exception: {
        userId: flowVars.queryParams.userId,
        Message: payload[1].exception.message
        }) when (payload.exception?) and 
                (payload[1].exception.action == "createUser") and
                (payload[0].exception.code != "-1"),
    (Exception: {
       userId: flowVars.queryParams.userId,
       Message: payload[0].exception.message
       }) when (payload.exception?) and 
            (payload[0].exception.action == "amendUser") and
            (payload[1].exception.replyStatus.code != "-1"),
}

Answer 1

你可以在这种情况下使用when/otherwise。你很接近，只需使用 { 和 } 而不是括号。大致如下：

%dw 1.0
%input payload application/json
%output application/xml
---
{
    Data: {
        userId: flowVars.queryParams.userId,
        Message: "User created successfully"
    }
}
when (payload[0].userResponse.category == "SUCCESS") and
     (payload[1].userResponse.category == "SUCCESS"))
otherwise
{
    Exception: {
        userId: flowVars.queryParams.userId,
        Message: payload[1].exception.message
    }
}