I am using a state machine builder to build state machine in my app.
Also the application has Action classes which implements org.springframework.statemachine.action.Action.
These Action classes are for executing entry actions for each stages.
If any exception is thrown from these Action classes, ie from execute(StateContext paramStateContext) method, I wanted to catch that exception and send an event(Terminated) and drive the state machine to End state, after updating the db with error details.
I tried to use state machine listener by overriding stateMachineError(StateMachine stateMachine, Exception e) method. But unfortunately this is not working.
Any other spring state machine component to catch exceptions, before I go to wrap the entire code in Action classes with try catch, and inside catch block sending the Terminated event so that state machine would navigate End state.
Here is the builder Iam using.
Builder<String, String> builder = StateMachineBuilder
.<String, String> builder();
builder.configureConfiguration()
.withConfiguration()
.autoStartup(false)
.listener(listener())
.beanFactory(
this.applicationContext.getAutowireCapableBeanFactory());
private StateMachineListener<String, String> listener() {
return new StateMachineListenerAdapter<String, String>() {
#Override
public void stateChanged(
org.springframework.statemachine.state.State<String, String> from,
org.springframework.statemachine.state.State<String, String> to) {
LOGGER.debug("State change to " + to.getId());
}
#Override
public void stateMachineError(
StateMachine<String, String> stateMachine, Exception e) {
e.printStackTrace();
LOGGER.debug("Ah... I am not getting executed when exception occurs from entry actions");
LOGGER.debug("Error occured from " + stateMachine.getState()
+ "and the error is" + e.toString());
}
};
}
Iam using 1.1.0.RELEASE version of spring-statemachine-core
You're correct, neither stateMachineError or a method annotated with #onStateMachineError are executed on an error. This is addressed in version 1.2, which is at milestone 1 right now. They introduced errorAction which is executed with the state machine context:
User can always catch exceptions manually but with actions defined for transitions it is possible to define error action which is called if exception is raised. Exception is then available from a StateContext passed to that action.
All that's needed is to specify an error action along with the desired action when defining a transition in the state machine configuration class. From the example in the documentation:
public void configure(StateMachineTransitionConfigurer<States, Events> transitions)
throws Exception {
transitions
.withExternal()
.source(States.S1)
.target(States.S2)
.event(Events.E1)
.action(action(), errorAction());
}
A detailed discussion of this can be found in Spring Statemachine issue #240.
Related
Spring 4.1.4
Hibernate 4.2.0
JDK 1.8
My context: I have a Controller calling --> Service --> calling Dao
The business funcionality is to delete ( in 1 to many DB relation) some child ,but not all child .
Then ,after deleting some child I try to delete the Parent and offcourse I got java.sql.SQLIntegrityConstraintViolationException
But the question is why transaction is market for Rollback ? ( in other words why I don't got the deletion of some child ?)
SQLIntegrityConstraintViolationException is a checked exception and stating Spring documentation the behaviour would be the same of EJB : Note that by default, rollback happens for runtime, unchecked exceptions only. The checked exception does not trigger a rollback of the transaction.
I need to remove some child anf trying to remove the parent if possible, if not I need to commit the transaction maintaining the parent and remaining of childs
Note I tried also to specify in Service and Dao methods the Spring Annotation
#Transactional(noRollbackFor = SQLIntegrityConstraintViolationException.class)
To request explicitly the behaviour expected , but not even like this work for me
Controller code method:
public void delete() {
FacesMessage msg = new FacesMessage(FacesMessage.SEVERITY_INFO, "Data deleted.","");
try{
memoTemplateService.delete(memoTemplate);
memoTemplates.remove(memoTemplate);
}
catch (Exception e){
msg=new FacesMessage(FacesMessage.SEVERITY_WARN, "A","B");
}
reset();
FacesContext.getCurrentInstance().addMessage(null, msg);
}
Service method :
#Override
#Transactional(noRollbackFor = {SQLIntegrityConstraintViolationException.class,DBConstraintException.class})
public void delete(MemoTemplate memoTemplate)throws BusinessException {
// deleting some ,not all , child
phaseAndMemoGenerator.deleteMemosForVisibleTimeHorizon(memoTemplate);
try{// some times Template cannot be deleted
memoTemplateDao.delete(memoTemplate);
}
catch (Exception e){
throw new DBConstraintException("Partial Delete", "Template cannot be deleted, Memo in the past are present");
}
}
Dao
#Repository(value = "memoTemplateDao")
public class MemoTemplateDaoImpl extends GenericJpaDaoImpl<MemoTemplate, Long> implements MemoTemplateDao {
#Override
#Transactional(noRollbackFor = SQLIntegrityConstraintViolationException.class)
public void delete(MemoTemplate t) {
super.delete(t);
em.flush();
}
}
Just an Update : it's incredible but I can't catch neither doing the catch in Dao method ,debugger go in catch block but before this still a java.sql.SQLIntegrityConstraintViolationException is fired , incredible !
#Transactional(noRollbackFor = {SQLIntegrityConstraintViolationException.class,PersistenceException.class})
public void tryToDelete(MemoTemplate t)throws Exception {
super.delete(t);
try{
em.flush();
}
catch (Exception e){
throw new Exception("ddddd");
}
}
If there are constraints defined in DB, you won't be able to bypass them by committing without rollback.
I have a reactive springboot application, in it an aspect
#Before("approveRejectPointcut()")
public void logAfterReturning(JoinPoint joinPoint) {
Status newStatus = AspectUtils.returnFirstParameterOfTypeOrFail(allParameters, Status.class, "approveRejectPointcut");
String comments = AspectUtils.returnFirstParameterOfTypeOrFail(allParameters, String.class, "approveRejectPointcut");
Mono<Object> someObjectOrException = someService.updateApplicationStatus(appId, newStatus, comments);
someObjectOrException
.subscribe(i->log.info(i),
error->{
log.info("we have some ex: "+error.getMessage());
throw new RuntimeException("PLEASE LORD: "+error.getMessage());
});
}
What happens here, the updateApplicationStatus() from some service throws at some point a Business exception(which is good), in this aspect I print the exception message, which is also good. However, when i try to throw a business exception (a RuntimeException at it's base) .. i can see this exception in the console, however.. it does not reach the client.
I suspect it is being thrown on a different thread. Any clues ?
In the end, changed the aspect to #Around
#Around("approveRejectPointcut()")
public Mono<Object> logAfterReturning(ProceedingJoinPoint pjp) {
...
Mono<Object> someObjectOrException = someService.updateApplicationStatus(appId, newStatus, comments);
someObjectOrException
.map(unused->pjp.proceed(pjp.getArgs())
.onErrorMap(RuntimeException.class, (s)->{
return new GenericBusinessException(s.getMessage());
});
}
this way in case all goes well in the service -> we carry on with the execution, otherwise, we throw our business exception with the exception message from the service. Perhaps that map() should be replaced with some other operator accepting a funtion.. :)
I try save list of entities to Oracle Db.
#Transactional
public void save() {
//logick
for (QuittanceType quittanceType : quittance) {
quittancesService.parseQuittance(quittanceType);
}
//logick
}
On each step I call this method:
#Transactional
#Override
public void parseQuittance(QuittanceType quittance) {
try {
//logick create payToChargeDb
paymentToChargeService.saveAndFlush(payToChargeDb);
} catch (Exception e) {
log.warn("Ignore.", e);
}
}
and method
#Override
public PaymentsToCharge saveAndFlushIn(PaymentsToCharge paymentsToCharge) {
return paymentToChargeRepository.saveAndFlush(paymentsToCharge);
}
When I try save entity with constraint My main transaction rollback and I get stacktrace:
Caused by: java.sql.BatchUpdateException: ORA-02290: CHECK integrity constraint violated(MYDB.PAYMENTS_TO_CHARGE_CHK1)
But I want skip not success entities and save success. I marck my method
#Transactional(propagation = Propagation.REQUIRES_NEW)
and it look like this:
#Transactional
#Override
public void parseQuittance(QuittanceType quittance) {
try {
//logick create payToChargeDb
paymentToChargeService.saveAndFlushInNewTransaction(payToChargeDb);
} catch (Exception e) {
log.warn("Ignore.", e);
}
}
and
#Transactional(propagation = Propagation.REQUIRES_NEW)
#Override
public PaymentsToCharge saveAndFlushInNewTransaction(PaymentsToCharge paymentsToCharge) {
return paymentToChargeRepository.saveAndFlush(paymentsToCharge);
}
But when I try save entity with constraint I not get exception and not enter to catcj block. just stop working debugging and the application continues to work. I do not get any errors. and as if rollback is happening
The proxy created by #Transactional does not intercept calls within the object.
In proxy mode (which is the default), only external method calls
coming in through the proxy are intercepted. This means that
self-invocation (in effect, a method within the target object calling
another method of the target object) does not lead to an actual
transaction at runtime even if the invoked method is marked with
#Transactional. Also, the proxy must be fully initialized to provide
the expected behavior, so you should not rely on this feature in your
initialization code (that is, #PostConstruct).
https://docs.spring.io/spring/docs/current/spring-framework-reference/data-access.html#transaction-declarative
The same documentation recommends use of AspectJ if you want this behaviour.
I am trying to log the exception in the spring boot based web service.
So I have used GlobalExceptionHandler
My code :
#ControllerAdvice
#RestController
public class GlobalExceptionHandler {
#ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
#ExceptionHandler(value = Exception.class)
public String handleException(Exception e){
System.out.println("Ankit == "+e.getMessage());
StringWriter errors = new StringWriter();
e.printStackTrace(new PrintWriter(errors));
System.out.println(errors.toString());
return e.getMessage();
}
}
the code is working fine. What I want is exception details. I mean the code where the exception occurs? File name / line ? or do I have to parse the stacktrace? I mean spring boot must have thought something for this?
Using IDE
If you are using any IDE then go to Console Window.
Clear console
Repeat action that causes Exception
Search in Console (CTRL + F) for ERROR
Look for line above(Look for 2-3 lines if you don't find immediate above) the line which contains ERROR. This line has details of Class, Method where Exception has occurred.
Without looking at Console or Logs
If you want to use it in production then, handling atleast known exceptions(like BAD_REQUEST, NOT_FOUND etc.) the way it is done below might be helpful (adding an extra parameter to Exception Class) :
Employee employee = employeeService.getEmployeeById(employeeId);
if (null == employee) {
logger.error("No tenant exists for employeeId:"+employeeId);
throw new ObjectNotFoundException("Emplyee Not Found", this.getClass().getSimpleName();));
}
here this.getClass().getSimpleName(); will be passed as parameter from EmployeeController class. So in ObjectNotFoundException we can add a parameter ClassName and When you handle it in GlobalExceptionHandler, you can do it as it is done below,
#ControllerAdvice
#RestController
public class GlobalExceptionHandler {
#ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
#ExceptionHandler(value = Exception.class)
public String handleException(Exception e){
System.out.println("Ankit == "+e.getMessage());
StringWriter errors = new StringWriter();
e.printStackTrace(new PrintWriter(errors));
String classWithExceptionName = e.getClassName();
// you need to add this above getter method to your Exception Class
System.out.println(errors.toString());
return e.getMessage();
}
}
This is for known common exceptions. We need to add extra parameter(ClassName) to All Custom Exceptions that you are throwing and that might be little extra code but i think that is the way. Hope it helps now.
Is there a way to get the reason a HystrixCommand failed when using the #HystrixCommand annotation within a Spring Boot application? It looks like if you implement your own HystrixCommand, you have access to the getFailedExecutionException but how can you get access to this when using the annotation? I would like to be able to do different things in the fallback method based on the type of exception that occurred. Is this possible?
I saw a note about HystrixRequestContext.initializeContext() but the HystrixRequestContext doesn't give you access to anything, is there a different way to use that context to get access to the exceptions?
Simply add a Throwable parameter to the fallback method and it will receive the exception which the original command produced.
From https://github.com/Netflix/Hystrix/tree/master/hystrix-contrib/hystrix-javanica
#HystrixCommand(fallbackMethod = "fallback1")
User getUserById(String id) {
throw new RuntimeException("getUserById command failed");
}
#HystrixCommand(fallbackMethod = "fallback2")
User fallback1(String id, Throwable e) {
assert "getUserById command failed".equals(e.getMessage());
throw new RuntimeException("fallback1 failed");
}
I haven't found a way to get the exception with Annotations either, but creating my own Command worked for me like so:
public static class DemoCommand extends HystrixCommand<String> {
protected DemoCommand() {
super(HystrixCommandGroupKey.Factory.asKey("Demo"));
}
#Override
protected String run() throws Exception {
throw new RuntimeException("failed!");
}
#Override
protected String getFallback() {
System.out.println("Events (so far) in Fallback: " + getExecutionEvents());
return getFailedExecutionException().getMessage();
}
}
Hopefully this helps someone else as well.
As said in the documentation Hystrix-documentation getFallback() method will be thrown when:
Whenever a command execution fails: when an exception is thrown by construct() or run()
When the command is short-circuited because the circuit is open
When the command’s thread pool and queue or semaphore are at capacity
When the command has exceeded its timeout length.
So you can easily get what raised your fallback method called by assigning the the execution exception to a Throwable object.
Assuming your HystrixCommand returns a String
public class ExampleTask extends HystrixCommand<String> {
//Your class body
}
do as follows:
#Override
protected ErrorCodes getFallback() {
Throwable t = getExecutionException();
if (circuitBreaker.isOpen()) {
// Log or something
} else if (t instanceof RejectedExecutionException) {
// Log and get the threadpool name, could be useful
} else {
// Maybe something else happened
}
return "A default String"; // Avoid using any HTTP request or ypu will need to wrap it also in HystrixCommand
}
More info here
I couldn't find a way to obtain the exception with the annotations, but i found HystrixPlugins , with that you can register a HystrixCommandExecutionHook and you can get the exact exception in that like this :
HystrixPlugins.getInstance().registerCommandExecutionHook(new HystrixCommandExecutionHook() {
#Override
public <T> void onFallbackStart(final HystrixInvokable<T> commandInstance) {
}
});
The command instance is a GenericCommand.
Most of the time just using getFailedExecutionException().getMessage() gave me null values.
Exception errorFromThrowable = getExceptionFromThrowable(getExecutionException());
String errMessage = (errorFromThrowable != null) ? errorFromThrowable.getMessage()
this gives me better results all the time.