Mule - how to get Mule to throw an exception if XML schema validation fails

Question

I'm using a Mule schema validation filter to validate an incoming XML file against a given scheme. Below is my configuration for the schema component:

<mulexml:schema-validation-filter schemaLocations="${app.home}/classes/schemas/Library.xsd" doc:name="Schema Validation"/>

The issue I'm having is that when a file fails to validate against the schema, Mule silently blocks the message from continuing - i.e. no error/exception is thrown. Through a little experimentation I discovered that if I add the following to my log4j.properties file, I can see the 'errors' in the schema validation:

log4j.logger.org.mule.module.xml.filters.SchemaValidationFilter=DEBUG

Since these errors are 'DEBUG' level logs and no actual exception is thrown, my flow doesn't revert to the exception strategy I've configured.

So the question I have is...

Is there something I can do here to make Mule revert to an exception strategy if there is an error in the schema validation? I've included a copy below of the debug logs that I see when a file fails to validate. Thanks in advance.

DEBUG 2014-04-15 11:19:20,705 [[processes].orderInputFileConnector.receiver.01] org.mule.module.xml.filters.SchemaValidationFilter: SchemaValidationFilter rejected a message because it apparently failed to validate against the schema.
org.xml.sax.SAXParseException: cvc-pattern-valid: Value 'string' is not facet-valid with respect to pattern '[A-Z]{2}' for type 'countryISOA2'.
    at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
    at org.apache.xerces.util.ErrorHandlerWrapper.error(Unknown Source)
    at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
    at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
    at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator$XSIErrorReporter.reportError(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator.reportSchemaError(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator.elementLocallyValidType(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator.processElementContent(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator.handleEndElement(Unknown Source)
    at org.apache.xerces.impl.xs.XMLSchemaValidator.endElement(Unknown Source)
    at org.apache.xerces.jaxp.validation.DOMValidatorHelper.finishNode(Unknown Source)
    at org.apache.xerces.jaxp.validation.DOMValidatorHelper.validate(Unknown Source)
    at org.apache.xerces.jaxp.validation.DOMValidatorHelper.validate(Unknown Source)
    at org.apache.xerces.jaxp.validation.ValidatorImpl.validate(Unknown Source)
    at org.mule.module.xml.filters.SchemaValidationFilter.accept(SchemaValidationFilter.java:107)
    at org.mule.routing.MessageFilter.accept(MessageFilter.java:89)
    at org.mule.processor.AbstractFilteringMessageProcessor.process(AbstractFilteringMessageProcessor.java:42)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.DefaultMessageProcessorChain.doProcess(DefaultMessageProcessorChain.java:95)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.AbstractInterceptingMessageProcessorBase.processNext(AbstractInterceptingMessageProcessorBase.java:106)
    at org.mule.interceptor.AbstractEnvelopeInterceptor.process(AbstractEnvelopeInterceptor.java:55)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.AbstractInterceptingMessageProcessorBase.processNext(AbstractInterceptingMessageProcessorBase.java:106)
    at org.mule.processor.AbstractFilteringMessageProcessor.process(AbstractFilteringMessageProcessor.java:44)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.AbstractInterceptingMessageProcessorBase.processNext(AbstractInterceptingMessageProcessorBase.java:106)
    at org.mule.construct.AbstractPipeline$1.process(AbstractPipeline.java:112)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.DefaultMessageProcessorChain.doProcess(DefaultMessageProcessorChain.java:95)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.doProcess(InterceptingChainLifecycleWrapper.java:54)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.access$001(InterceptingChainLifecycleWrapper.java:26)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper$1.process(InterceptingChainLifecycleWrapper.java:70)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.process(InterceptingChainLifecycleWrapper.java:65)
    at org.mule.construct.AbstractPipeline$3.process(AbstractPipeline.java:204)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.SimpleMessageProcessorChain.doProcess(SimpleMessageProcessorChain.java:47)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.AbstractInterceptingMessageProcessorBase.processNext(AbstractInterceptingMessageProcessorBase.java:106)
    at org.mule.processor.AbstractFilteringMessageProcessor.process(AbstractFilteringMessageProcessor.java:44)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.SimpleMessageProcessorChain.doProcess(SimpleMessageProcessorChain.java:47)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.doProcess(InterceptingChainLifecycleWrapper.java:54)
    at org.mule.processor.chain.AbstractMessageProcessorChain.process(AbstractMessageProcessorChain.java:70)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.access$001(InterceptingChainLifecycleWrapper.java:26)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper$1.process(InterceptingChainLifecycleWrapper.java:70)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:27)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:61)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:47)
    at org.mule.processor.chain.InterceptingChainLifecycleWrapper.process(InterceptingChainLifecycleWrapper.java:65)
    at org.mule.transport.AbstractMessageReceiver.routeEvent(AbstractMessageReceiver.java:473)
    at org.mule.transport.AbstractMessageReceiver.routeMessage(AbstractMessageReceiver.java:226)
    at org.mule.transport.AbstractMessageReceiver.routeMessage(AbstractMessageReceiver.java:208)
    at org.mule.transport.AbstractMessageReceiver.routeMessage(AbstractMessageReceiver.java:200)
    at org.mule.transport.AbstractMessageReceiver.routeMessage(AbstractMessageReceiver.java:187)
    at org.mule.transport.file.FileMessageReceiver.moveAndDelete(FileMessageReceiver.java:560)
    at org.mule.transport.file.FileMessageReceiver.access$400(FileMessageReceiver.java:62)
    at org.mule.transport.file.FileMessageReceiver$2.process(FileMessageReceiver.java:410)
    at org.mule.transport.file.FileMessageReceiver$2.process(FileMessageReceiver.java:406)
    at org.mule.execution.ExecuteCallbackInterceptor.execute(ExecuteCallbackInterceptor.java:20)
    at org.mule.execution.HandleExceptionInterceptor.execute(HandleExceptionInterceptor.java:34)
    at org.mule.execution.HandleExceptionInterceptor.execute(HandleExceptionInterceptor.java:18)
    at org.mule.execution.BeginAndResolveTransactionInterceptor.execute(BeginAndResolveTransactionInterceptor.java:58)
    at org.mule.execution.ResolvePreviousTransactionInterceptor.execute(ResolvePreviousTransactionInterceptor.java:48)
    at org.mule.execution.SuspendXaTransactionInterceptor.execute(SuspendXaTransactionInterceptor.java:54)
    at org.mule.execution.ValidateTransactionalStateInterceptor.execute(ValidateTransactionalStateInterceptor.java:44)
    at org.mule.execution.IsolateCurrentTransactionInterceptor.execute(IsolateCurrentTransactionInterceptor.java:44)
    at org.mule.execution.ExternalTransactionInterceptor.execute(ExternalTransactionInterceptor.java:52)
    at org.mule.execution.RethrowExceptionInterceptor.execute(RethrowExceptionInterceptor.java:32)
    at org.mule.execution.RethrowExceptionInterceptor.execute(RethrowExceptionInterceptor.java:17)
    at org.mule.execution.TransactionalErrorHandlingExecutionTemplate.execute(TransactionalErrorHandlingExecutionTemplate.java:113)
    at org.mule.execution.TransactionalErrorHandlingExecutionTemplate.execute(TransactionalErrorHandlingExecutionTemplate.java:34)
    at org.mule.transport.file.FileMessageReceiver.processWithoutStreaming(FileMessageReceiver.java:405)
    at org.mule.transport.file.FileMessageReceiver.processFile(FileMessageReceiver.java:397)
    at org.mule.transport.file.FileMessageReceiver.poll(FileMessageReceiver.java:238)
    at org.mule.transport.AbstractPollingMessageReceiver.performPoll(AbstractPollingMessageReceiver.java:219)
    at org.mule.transport.PollingReceiverWorker.poll(PollingReceiverWorker.java:84)
    at org.mule.transport.PollingReceiverWorker.run(PollingReceiverWorker.java:53)
    at org.mule.work.WorkerContext.run(WorkerContext.java:311)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:744)

UPDATE

Following the answer provided by @RyanCarter (which worked), I've also found the following solution which doesn't give any errors inside of Mule Studio. It involves defining the Schema Validation Filter globally and referencing it inside a message filter like so:

<mulexml:schema-validation-filter name="myValidator".../>

<flow>          
    <message-filter throwOnUnaccepted="true">
       <filter ref="myValidator"/>
    </message-filter>

score 8 · Accepted Answer · answered Apr 15 '14 at 12:40

8

You can wrap the schema-validation-filter in a message-filter and set throwOnUnaccepted to "true":

<message-filter throwOnUnaccepted="true">
   <mulexml:schema-validation-filter... />
</message-filter>

You can then use an exception-strategy to handle the exception.

answered Apr 15 '14 at 12:40

Ryan Carter

11,441
2
20
27

Thanks @Ryan. I've just given this option a go, and I get an error saying 'Nested Filter is missed' on the `` element? – danw Apr 15 '14 at 12:44
That's just Studio whining :). If you run it it should work. It does for me. Let me know – Ryan Carter Apr 15 '14 at 12:55
Yep, this worked. I've also found an alternative which doesn't result in the annoying studio error. I've added this to the original post. – danw Apr 15 '14 at 13:07

score 1 · Answer 2 · answered Apr 15 '14 at 12:25

1

The purpose of the filter is to stop the processing if the condition is no satisfied. They usually don't throw exception and disrupt the flow. If you have to get the exception and handle it then try using errorHandler-ref property in the filter and point it to the spring bean that can handle the error.

<mulexml:schema-validation-filter  errorHandler-ref="" ></mulexml:schema-validation-filter>

Hope this helps.

answered Apr 15 '14 at 12:25

user1760178

6,277
5
27
57

Thank you for your response. I've never actually dealt with an error in this way - do you have an example of something similar that I could use or adapt? – danw Apr 15 '14 at 12:30

vikas sahu · Answer 3 · 2015-11-28T16:54:26.347

If you want to use errorHandler-ref="" in schema validation just create a java component which implements ErrorHandler. In java component you can handle any kind of validation error and process accordingly. Here is the code snippet

<mulexml:schema-validation-filter
    schemaLocations="abc.xsd"
    errorHandler-ref="Bean" returnResult="true" doc:name="Schema Validation"
    name="xmlvalidation" schemaLanguage="http://www.w3.org/2001/XMLSchema" />

created BEAN in Mule as -

<spring:beans>
  <spring:bean id="Bean" name="Bean" class="com.training.ErrorHandler"/>
</spring:beans>

create one java class and implement "org.xml.sax.ErrorHandler" like as below -

package com.training;

import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

public class ErrorHandler implements org.xml.sax.ErrorHandler{

public ErrorHandler() {
    super();
    // TODO Auto-generated constructor stub
}

@Override
public void warning(SAXParseException exception) throws SAXException {
    System.out.println("do something here");

}

@Override
public void error(SAXParseException exception) throws SAXException {
    System.out.println("do something here");


}

@Override
public void fatalError(SAXParseException exception) throws SAXException {
    System.out.println("do something here");

}

}

It's unclear how this answers the question- please add some details. — AStopher, Nov 25 '15 at 18:33

Mule - how to get Mule to throw an exception if XML schema validation fails

3 Answers3