Does anybody know how to handle Unchecked / Runtime Exceptions in MULE..??
I mean, in my java code, for a certain reason , i am "throwing an Exception" and i want Mule to detect it and route it to proper flow , where i can Log or Print that Exception.
So , What exactly should i place in my "flow" in Mule Config File to achieve that.
My Java code :
public Object xyz (Map payload) throws Exception {
if (payload.isEmpty()) {
throw new Exception ("New Exception") ;
}
}
My Mule Config file :
<flow name="APIAuthenticate">
<http:inbound-endpoint address="http://localhost:1212/jcore/authorize" transformer-refs="HttpParams" responseTransformer-refs="JavaObjectToJson" contentType="application/json" encoding="UTF-8">
<not-filter>
<wildcard-filter pattern="/favicon.ico"/>
</not-filter>
</http:inbound-endpoint>
<component class="main.java.com.abc.XYZ"/>
</flow>
Any help will be deeply appreciated..!!
Configuring a default-exception-strategy in your flow should allow you to catch the exceptions (even runtime ones) and deal with them.
Read the error handling reference guide for more info.
Ok..i did some hit and trial and i figured out that
When the Exception is thrown, an Exception Strategy is required like default-exception-strategy OR custom-exception-strategy is required, that would route the flow to some Class that would handle it and do required Actions.
But When we Return an Exception (like below), then we can use the exception-payload-filter or choice attribute of Mule to handle it.
public Object xyz (Map payload) throws Exception {
if (payload.isEmpty()) {
return new Exception ("New Exception") ;
}
}
Please Correct me if i am wrong..??
Also if there are other answers to this question, please be kind to put them..
Related
public UserMailDto getUserByEmail(String email) throws UserExceptionMessage {
try {
return userRepository.searchByMail(email);
} catch (DataAccessException | JDBCConnectionException accessException) {
com.example.user_service.config.log.Logger.errorLog("UserService", accessException.getMessage());
throw new DataAccessExceptionMessage(Messages.ERROR_TRY_AGAIN + accessException.getMessage());
}
}
In my view you should handle it, but not with a try..catch block in what seems to be your service. Why are you catching the Exception and then rethrowing you own custom Exception with a message? You will need to handle that Exception at some point in your code to. So you are not really handling it here.
It looks like you are building a web app, so I would recommend that you handle your Exceptions in one central place in a #ControllerAdvice class. You can read about it here. This way you can really handle the Exception, by returning a corresponding status code to the user. 503 in your case.
I am using Avro and Schema registry with my Spring Kafka setup.
I would like to somehow handle the SerializationException, which might be thrown during deserialization.
I found the following two resource:
https://github.com/spring-projects/spring-kafka/issues/164
How do I configure spring-kafka to ignore messages in the wrong format?
These resources suggest that I return null instead of throwing an SerializationException when deserializing and listen for KafkaNull. This solution works just fine.
I would however like to be able to throw an exception instead of returning null.
KIP-161 and KIP-210 provide better features to handling exceptions. I did find some resources mentioning KIP-161 in Spring Cloud, but nothing specific about Spring-Kafka.
Does anyone know how to catch SerializationException in Spring Boot?
I am using Spring Boot 2.0.2
Edit: I found a solution.
I would rather throw an exception and catch it than having to return null or KafkaNull. I am using my custom Avro serializer and deserializer in multiple different project, some of which are not Spring. If I changed my Avro serializer and deserializer then some of the other projects would need to be changed to expect the deserializer to return null.
I would like to shutdown the container, such that I do not lose any messages. The SerializationException should never be expected in production. The SerializationException should only be able to happen if Schema Registry is down or if an unformatted message somehow is sent to the production kafka. Either way, SerializationException should only happen very rarely, and if it happens then I want to shutdown the container such that no messages are lost and I can investigate the issue.
Just take into consideration that will catch all exceptions from your consumer container. In my specific case I just want to only shutdown if it is a SerializationException
public class SerializationExceptionHandler extends ContainerStoppingErrorHandler {
#Override
public void handle(Exception thrownException, List<ConsumerRecord<?, ?>> records, Consumer<?, ?> consumer,
MessageListenerContainer container) {
//Only call super if the exception is SerializationException
if (thrownException instanceof SerializationException) {
//This will shutdown the container.
super.handle(thrownException, records, consumer, container);
} else {
//Wrap and re-throw the exception
throw new KafkaException("Kafka Consumer Container Error", thrownException);
}
}
}
This handler is passed to the consumer container. Below is an example of a
KafkaListenerContainerFactory bean.
#Bean
public KafkaListenerContainerFactory<ConcurrentMessageListenerContainer<Integer, String>>
kafkaListenerContainerFactory(JpaTransactionManager jpa, KafkaTransactionManager<?, ?> kafka) {
ConcurrentKafkaListenerContainerFactory<Integer, String> factory =
new ConcurrentKafkaListenerContainerFactory<>();
factory.setConsumerFactory(consumerFactory());
factory.setConcurrency(1);
factory.getContainerProperties().setPollTimeout(3000);
factory.getContainerProperties().setErrorHandler(new SerializationExceptionHandler());
factory.getContainerProperties().setTransactionManager(chainedTxM(jpa, kafka));
return factory;
}
There is nothing Spring can do; the deserialization occurs before the consumer gets any data. You need to enhance the deserializer.
I would however like to be able to throw an exception instead of returning null.
That won't help anything since Kafka won't know how to deal with the exception. Again; this all happens before the data is available so returning null (or some other special value) is the best technique.
EDIT
In 2.2, we added an error handling deserializer which delegates to the actual deserializer and returns null, with the exception in a header; the listener container then passes this directly to the error handler instead of the listener.
As per Customizing Error Handling "Throwing the exception in the catch block will forward the message to the error queue. If that's not desired, remove the throw from the catch block to indicate that the message has been successfully processed." That's not true for me even if I simply swallow any kind of exception in a behavior:
public override async Task Invoke(IInvokeHandlerContext context, Func<Task> next)
{
try
{
await next().ConfigureAwait(false);
}
catch (Exception ex)
{
}
}
I put a breakpoint there and made sure execution hit the catch block. Nevertheless after intimidate and delayed retries messages inevitably ends up in error queue. And I have no more Behaviours in the pipeline besides this one.
Only if I run context.DoNotContinueDispatchingCurrentMessageToHandlers(); inside the catch block it prevents sending error to the error queue, but it also prevents any further immediate and delayed retries.
Any idea on why it works in contravention of Particular NserviceBus documentation is very appreciated
NserviceBus ver. used: 6.4.3
UPDATE:
I want only certain type of exceptions not being sent to an error queue in NServiceBus 6, however to make test case more clear and narrow down the root cause of an issue I use just type Exception. After throwing exception, execution certainly hits the empty catch block. Here is more code to that:
public class EndpointConfig : IConfigureThisEndpoint
{
public void Customize(EndpointConfiguration endpointConfiguration)
{
endpointConfiguration.DefineEndpointName("testEndpoint");
endpointConfiguration.UseSerialization<XmlSerializer>();
endpointConfiguration.DisableFeature<AutoSubscribe>();
configure
.Conventions()
.DefiningCommandsAs(t => t.IsMatched("Command"))
.DefiningEventsAs(t => t.IsMatched("Event"))
.DefiningMessagesAs(t => t.IsMatched("Message"));
var transport = endpointConfiguration.UseTransport<MsmqTransport>();
var routing = transport.Routing();
var rountingConfigurator = container.GetInstance<IRountingConfiguration>();
rountingConfigurator.ApplyRountingConfig(routing);
var instanceMappingFile = routing.InstanceMappingFile();
instanceMappingFile.FilePath("routing.xml");
transport.Transactions(TransportTransactionMode.TransactionScope);
endpointConfiguration.Pipeline.Register(
new CustomFaultMechanismBehavior(),
"Behavior to add custom handling logic for certain type of exceptions");
endpointConfiguration.UseContainer<StructureMapBuilder>(c => c.ExistingContainer(container));
var recoverability = endpointConfiguration.Recoverability();
recoverability.Immediate(immediate =>
{
immediate.NumberOfRetries(2);
});
endpointConfiguration.LimitMessageProcessingConcurrencyTo(16);
recoverability.Delayed(delayed =>
{
delayed.NumberOfRetries(2);
});
endpointConfiguration.SendFailedMessagesTo("errorQueue");
...
}
}
public class CustomFaultMechanismBehavior : Behavior<IInvokeHandlerContext>
{
public override async Task Invoke(IInvokeHandlerContext context, Func<Task> next)
{
try
{
await next().ConfigureAwait(false);
}
catch (Exception ex)
{
}
}
}
UPDATE 2
I think I know what's going on: message is handled by first handler that throws an exception which is caught by the Behavior catch block, but then NServiceBus runtime tries to instantiate second handler class which is also supposed to handle the message (it handles class the message is derived from). That's where another exception is thrown in a constructor of one of dependent class. StructureMap tries to instantiate the handler and all its dependent services declared in the constructor and in the process runs into the exception. And this exception is not caught by CustomFaultMechanismBehavior.
So my I rephrase my question now: Is there any way to suppress errors (ignore error queue) occurring inside constructor or simply during StructureMap classes initialization? Seems like the described way does not cover this kind of situations
Your behavior is activated on Handler invocation. This means you are catching exceptions happening inside the Handle method so any other exception, e.g. in the Constructor of the handler would not be caught.
To change the way you 'capture' the exceptions, you can change the way the behavior is activated, e.g. change it from Behavior<IInvokeHandlerContext> to Behavior<ITransportReceiveContext> which is activated when the transport receives a message. You can investigate on different stages and behaviors to see which one suits your purpose best.
Using Spring Integration with RabbitMQ in my project I face a problem.
The project consist of receiving messaging from a queue, trace the incoming message, process the message using a service-activator, and trace the response or the exception thrown by the service activator.
Here is the sample configuration:
<!-- inbound-gateway -->
<int-amqp:inbound-gateway id="inboundGateway"
request-channel="gatewayRequestChannel"
queue-names="myQueue"
connection-factory="rabbitMQConnectionFactory"
reply-channel="gatewayResponseChannel"
error-channel="gatewayErrorChannel"
error-handler="rabbitMQErrorHandler"
mapped-request-headers="traceId"
mapped-reply-headers="traceId" />
<!-- section to dispatch incoming messages to trace and execute service-activator -->
<int:publish-subscribe-channel id="gatewayRequestChannel" />
<int:bridge input-channel="gatewayRequestChannel" output-channel="traceChannel"/>
<int:bridge input-channel="gatewayRequestChannel" output-channel="serviceActivatorInputChannel"/>
<!-- the trace channel-->
<int:logging-channel-adapter id="traceChannel"
expression="headers['traceId'] + '= [Headers=' + headers + ', Payload=' + payload+']'" logger-name="my.logger" level="DEBUG" />
<!-- service activator which may throw an exception -->
<int:service-activator ref="myBean" method="myMethod" input-channel="serviceActivatorInputChannel" output-channel="serviceActivatorOutputChannel"/>
<!-- section to dispatch output-messages from service-activator to trace them and return them to the gateway -->
<int:publish-subscribe-channel id="serviceActivatorOutputChannel" />
<int:bridge input-channel="serviceActivatorOutputChannel"
output-channel="traceChannel" />
<int:bridge input-channel="serviceActivatorOutputChannel"
output-channel="gatewayResponseChannel" />
<!-- section to dispatch exceptions from service-activator to trace them and return them to the gateway -->
<int:bridge input-channel="gatewayErrorChannel"
output-channel="traceChannel" />
<int:bridge input-channel="gatewayErrorChannel"
output-channel="gatewayResponseChannel" />
I simplified the code to suit my explanation. The idea is to trace the input and output/error messages coming and outgoing to/from the service-activator. To do this, I use a message's header named traceId. This identifier is used as a correlation-identifier to be able to associate the request-message with its response (these two messages share the same traceId value).
Everything is working fine when no exception is thrown by the service-activator.
But when an exception is thrown, it seems a new message is generated by the gateway, without my original traceId header.
Looking a little bit into the gateway code, I find the following piece of code into the class org.springframework.integration.gateway.MessagingGatewaySupport :
private Object doSendAndReceive(Object object, boolean shouldConvert) {
...
if (error != null) {
if (this.errorChannel != null) {
Message<?> errorMessage = new ErrorMessage(error);
Message<?> errorFlowReply = null;
try {
errorFlowReply = this.messagingTemplate.sendAndReceive(this.errorChannel, errorMessage);
}
...
}
It seems that, when an exception occurred, a new message is created with the exception message as payload and is sent to the gateway's errorChannel. Here is where I loose my custom headers.
Is there a way to preserve my custom-headers when an exception is occurring? (maybe there is a way to configure it and I may be missing it...). Or maybe I am not implementing my flow in a right way. If this is the case, any comment or suggestion is welcome.
By the way, I am using the version 4.0.3.RELEASE of the spring-integration-core artifact.
Thanks for yours answers
Edit: as Gary Russel said, this exemple is missing the following puslish/subscribe queue configuration
<int:publish-subscribe-channel id="gatewayErrorChannel"/>
The message on the error-channel is an ErrorMessage. It has two properties: cause - the original exception and failedMessage - the message at the point of failure. The ErrorMessage does not get the failedMessage's headers.
You can't just send the ErrorMessage back to the gateway without some extra work.
Typically, error flows will perform some analysis of the error before returning a response.
If you want to restore some custom header, you will need a header enricher on the error flow.
Something like
<int:header-enricher ...>
<int:header name="traceId" expression="payload.failedMessage.headers.traceId" />
</int:header-enricher>
In addition, your configuration is a little odd in that you have 2 subscribers on gatewayErrorChannel. Unless it is a <publish-subscribe-channel/>, these consumers will get alternate messages; it seems like you expect them both to get it so you need to declare the channel properly.
I have a WCF service configured to use custom UserName validation via the overriden Validate() method of the System.IdentityModel.Selectors.UserNamePasswordValidator class.
All methods of the contract have been decorated with the FaultContractAttribute to specify a custom SOAP fault as being returnable.
When throwing FaultException<T>, where T is the type specified in the FaultContractAttribute, everything behaves as expected and I get the custom fault in the response XML.
However, if I try and throw FaultException<T> in the overriden Validate() method of the username authentication class, I get a generic SOAP fault with the following reason:
"The creator of this fault did not specify a Reason."
However, if I change the code to throw the general SOAP fault as in:
throw new FaultException("Authentication failed.");
I will at least get "Authentication failed." in the reason element.
My questions are:
Why aren't the FaultException<T> exceptions treated the same if they're thrown in the Validate() as they are within the service implementation?
Is it possible to have exceptions thrown in the Validate() method conform to the FaultContractAttribute specified on the contract methods?
Any help greatly appreciated. My own guess is that the authentication comes before the message is associated with any method of the contract, and therefore, is not associated with the FaultContractAttribute, but any article confirming this and giving a workaround would be very useful.
Tali
It's a bit annoying but I got round it by doing this:
SecurityTokenValidationException stve
= new SecurityTokenValidationException("Invalid username or password");
throw new FaultException<SecurityTokenValidationException>(stve, stve.Message);
Including the message additionally means that you don't get the silly "did not specify a reason" message.
The problem is that the custom validation code is running outside of the context of any specific OperationContract, so there is no FaultContract is place for WCF to handle. So the short answer is no, you cannot get the exceptions thrown from your custom validator to honor the FaultContract.
You have a few options here. The one I prefer is to throw the non-generic FaultException and provide a pre-determined FaultCode; this way my catch blocks can differentiate contract faults from "plumbing" faults. Note that any exception you throw from a custom validator should come back as a MessageSecurityException, as shown below:
// Custom Validator:
public override void Validate(string userName, string password)
{
throw new FaultException(
"Invalid username or password.",
new FaultCode("AUTHENTICATION_FAILURE"));
}
// Client Code:
try
{
client.DoSomething();
}
catch ( MessageSecurityException ex )
{
var inner = ex.InnerException as FaultException;
if (inner != null && inner.Code.Name.Equals("AUTHENTICATION_FAILURE"))
{
// Security failure.
}
}
catch ( FaultException<SomethingFault> ex )
{
// Exception from the method itself.
}