我正在尝试在数据编织中进行以下转换
%dw 1.0
%input in application/json
%output application/json
---
flowVars["xyz"]
“xyz”变量本身就是一个JSON对象。我问这个是因为我需要将两个有效负载（有效负载+变量）合并为一个JSON对象，这是第一步。
另外如果我提供Payload而不是flowVars [“xyz”]，那么我得到相同的错误.Payload也是相同类型的JSON对象。
以下是堆栈跟踪
Root Exception stack trace:
com.mulesoft.weave.writer.json.JsonInvalidStructureException: JSON can only have one top-level value and that value can only be either an array or an object
at com.mulesoft.weave.writer.json.JsonWriter.value(JsonWriter.scala:44)
at com.mulesoft.weave.writer.json.JsonWriter.value(JsonWriter.scala:36)
at com.mulesoft.weave.engine.Engine.internalExecute(Engine.scala:88)
at com.mulesoft.weave.engine.Engine.execute(Engine.scala:53)
at com.mulesoft.weave.engine.Engine.execute(Engine.scala:181)
at com.mulesoft.weave.mule.WeaveMessageProcessor$WeaveOutputHandler.write(WeaveMessageProcessor.scala:198)
at org.mule.transformer.simple.ObjectToString.createStringFromOutputHandler(ObjectToString.java:102)
at org.mule.transformer.simple.ObjectToString.doTransform(ObjectToString.java:56)
at org.mule.transformer.AbstractTransformer.transform(AbstractTransformer.java:415)
at org.mule.transformer.AbstractTransformer.transform(AbstractTransformer.java:366)
at org.mule.DefaultMuleMessage.transformMessage(DefaultMuleMessage.java:1606)
at org.mule.DefaultMuleMessage.applyAllTransformers(DefaultMuleMessage.java:1509)
at org.mule.DefaultMuleMessage.applyTransformers(DefaultMuleMessage.java:1487)
at org.mule.DefaultMuleMessage.applyTransformers(DefaultMuleMessage.java:1479)
at org.mule.transformer.AbstractTransformer.process(AbstractTransformer.java:114)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:107)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:94)
at org.mule.processor.BlockingProcessorExecutor.execute(BlockingProcessorExecutor.java:56)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:94)
at org.mule.processor.BlockingProcessorExecutor.execute(BlockingProcessorExecutor.java:56)
at org.mule.processor.AsyncInterceptingMessageProcessor.process(AsyncInterceptingMessageProcessor.java:102)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:107)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:94)
at org.mule.processor.BlockingProcessorExecutor.execute(BlockingProcessorExecutor.java:56)
at org.mule.construct.DynamicPipelineMessageProcessor.process(DynamicPipelineMessageProcessor.java:55)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:107)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:85)
at org.mule.processor.BlockingProcessorExecutor.execute(BlockingProcessorExecutor.java:56)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:94)
at org.mule.processor.BlockingProcessorExecutor.execute(BlockingProcessorExecutor.java:56)
at org.mule.interceptor.AbstractEnvelopeInterceptor.processBlocking(AbstractEnvelopeInterceptor.java:58)
at org.mule.processor.AbstractRequestResponseMessageProcessor.process(AbstractRequestResponseMessageProcessor.java:47)
at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:107)
at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)
at org.mule.processor.BlockingProcessorExecutor.executeNext(BlockingProcessorExecutor.java:94)
at org.mule.processor.BlockingProcessorExecutor.execute(Blocking...
如果需要更多信息，请告诉我
答案 0 :(得分：0)
您需要将flowVar中的mime-type设置为application/json。
如果不是，你需要为你的有效载荷设置它。