What does 'segment' and 'progress' mean in that kind of exception
2) xlang/s engine event log entry: Uncaught exception (see the 'inner exception' below) has suspended an instance of service 'MainEventProcess.MainEvent(5b530a24-7336-4695-78ee-1d4ffdd9f210)'.
The service instance will remain suspended until administratively resumed or terminated.
If resumed the instance will continue from its last persisted state and may re-throw the same unexpected exception.
InstanceId: cf584087-a9d3-4be7-8da7-eae49fd4a108
Shape name: SendDeviationOut
ShapeId: dc5c3484-7955-4d75-b1f9-7e0ca8ecbc1e
Exception thrown from: segment 4, progress 8
Inner exception: Exception occurred when persisting state to the database.
Full details hereon MSDN:
Exception during execution of Orchestration
Can it be helpful in searching errors in code?
First, it's nothing you need to worry about and is not related to your app/code/implementation.
The two items you need to act on are SendDeviationOut and Exception occurred when persisting state to the database. You are most likely publishing a message and there are no Subscribers. This is the "no Subscribers found" error from the Orchestration engine.
Now, to answer your specific question, those are markers to blocks of C# code that XLang compiler generated from your Orchestration. Basically, every statement is organized into a group, segment, and each is executed and tracked individually, progress. If you open the File0.cs, you will see this in action.
Related
I've a question regarding capture of "uncaught" exceptions, which appears with stack trace on System.err, circumventing logging configuration: All the other log messages appear properly formatted on System.out (JSON-formatted in my case). But this doesn't happen with Exceptions and stack traces "logged" to System.err!
I've recognized this to happen under at least two circumstances:
Asynchronous execution of tasks (HTTP requests in my case) via ExecutorService (as mentioned in "Scheduled Tasks" chapter). I've added #Retryable annotation to the method; but after all retries fail, "final" Exception thrown by last unsuccessful retry appears on System.err with its stack trace (the other ones thrown by earlier failed retries do not appear, seems they are caught by retry "mechanism" under the hood).
With Exceptions thrown by failed Health indicators (they are implemented by subclassing AbstractHealthIndicator).
I've tried implementing my own TaskExceptionHandler, replacing the default one (also mentioned in "Scheduled Tasks" chapter); and/or by adding System.setErr(System.out) in main method before building/setup of Micronaut Application Context. But nothing seems to help as my test cases attest.
Have I missed a chapter in Micronaut's documentation?
Thanks for any hints.
Regards
Christian
My wager is that Micronaut doesn't provide tools for setting a global uncaught exception handler because that's governed by the wider JRE. We've solved the problem in a few of our services with Thread.html#setDefaultUncaughtExceptionHandler by doing something like this at application startup:
Thread.setDefaultUncaughtExceptionHandler((t, e) -> logger.error("Uncaught exception", e));
I have an Apache Camel route which handles messages from a queue. To better understand what is happening at runtime I also keep the execution state in a database (number of retries, last execution state,...). I would like to use the redelivery mechanism from the exception handler but which performs some processing on every failure to update my database record.
from("jms:myinputqueue")
.onException(RetriableException.class)
.maximumRedeliveries(5)
.maximumRedeliveryDelay(10000)
.useOriginalMessage()
.to("log:store error information in database about each attempt") // (1)
.end() // onException
.to("log:apply business logic here which can throw exceptions")
;
The part (1) is only executed after all retries are exhausted, so only once.
I've read Apache Camel- Message Redelivery happens before onexception block executes but the suggested solution ''onRedelivery'' is executed before the beginning of a new retry. I need to store the result on each failure so I can save the last state (error message) in the database.
Any suggestions ?
There is an onExceptionOccurred processor you can use that is called when the exception happened.
Its included in Camel 2.17 onwards: https://issues.apache.org/jira/browse/CAMEL-9069
Does anybody know how to print full stack trace on the Browser, when a Runtime Exception occurs in MULE..??
When a runtime Exception occurs, MULE throws a 500 Server Error to the client , but shows no details to the client. It prints the whole stack trace in Console or Log Files (like the following) :
Root Exception stack trace:
java.sql.SQLException: Invalid column name
at oracle.jdbc.driver.OracleStatement.getColumnIndex(OracleStatement.java:3677)
at oracle.jdbc.driver.OracleResultSetImpl.findColumn(OracleResultSetImpl.java:2749)
at oracle.jdbc.driver.OracleResultSet.getString(OracleResultSet.java:494)
+ 3 more (set debug level logging or '-Dmule.verbose.exceptions=true'
for everything)
Can i show the same stack Trace on the Browser (to the client)..??
And if possible , then also tell me how to switch ON or OFF printing of Stack Trace on Browser..??
(It may be possible that sometime in future , i dont want to show stack trace on browser)
Yes this is possible. I assume you are using a regular HTTP endpoint and this is a REST type service(?) If so, you can simply put a try/catch around the code causing the exception and return whatever text you want.
There are also exception strategies (http://www.mulesoft.org/documentation/display/MULE3USER/Error+Handling) for doing more sophisticated error handling, but it sounds like you are looking for the simple answer above.
If this doesn't answer your question, please provide more info about your mule config and the service that is raising the exception.
There is nothing out of the box in Mule to do that. You have to implement an exception handler that will format the stacktrace in the Message exception payload and return it to the caller.
In your case, the HTTP transport has a particularity that can be found in the HttpMessageReceiver code:
try
{
conn.writeResponse(processRequest(request));
}
catch (Exception e)
{
...
conn.writeResponse(buildFailureResponse(request.getRequestLine().getHttpVersion(), httpStatus, e.getMessage()));
This means that when an exception crops-up to the top level, the creation of the failure message response is not customizable: you get this pretty technical message back and that is all.
I see two options to solve your problem:
sub-class HttpMessageReceiver and make the response message customizable in your version,
drop the HTTP transport in favor of the Jetty one (look at the bookstore example) and customize the response error messages at the web container level.
I have a windows service, in which I want a top level try-catch that catches any otherwise unhandled (or bubbled) exception, logs it to the Event Log and then swallows it so the service keeps running. However, I can't find any overload to System.Diagnostics.EventLog.WriteEntry that takes an exception as a parameter - is there no way to just give the event log the exception and let it parse out the message on its own?
Unfortunately there is no standard way of just passing the Exception to the Eventlog, built in to the .NET framework.
To have an exception written to the EventLog with the smallest development effort, you would need to write something like:
EventLog myLog = new EventLog();
myLog.Source = "Your Source";
myLog.WriteEntry(exception.ToString(), EventLogEntryType.Error);
But normally you would try to do some formatting of your exception.
Does throwing an exception in a windows service crash the service?
i.e. it will have to be restarted manually
Note:
I am throwing the exception from within the catch clause.
Not strictly so -- it'd only cause problems if the exception is unhandled.
If the exception is uncaught and bubbles back up to the OnStart() method it will crash the service. You will typically see a message in the Windows Event Log similar to the following:
"The MyServiceName Service service terminated unexpectedly. It has done this x time(s).
If you're throwing the exception in Catch, and there's nothing above it to recatch it, then that will cause your service to stop. The OnStart() method needs a try/catch. If you don't want to stop the service when an Exception occurs, then you need to handle it (log it and move on, or whatever).
My preference woudld be to handle expected exceptions, and to have unexpected exceptions either cause the service to stop, or at least stop/restart automatically. If something unexpected happens your service will be running in an unknown state, and who knows what it will do.
We ran into the problem of an untrapped exception on a child thread causing the service to stop without providing any information about what was causing the exception. We used this method to find out the source of the exception.
You can put a Handler to the service to catch all unhandled exceptions (including all sub threads of the service). In VB.NET, you will need to add a handler for AppDomain.CurrentDomain.UnhandledException. It is likely similar in C#. It will then catch anything that does bubble up past your onStart. You can choose to consume it there or allow it to crash the service from there.