When we invoke the Dts.Events.FireError method in a script task, we provide the description as the third parameter. This is available to error handlers in the variable System::ErrorDescription. Is the second parameter called SubComponent available to error handlers anywhere, and if so where?
There are no variables called subcomponent. This is a field that you can use to help classify the source of an error. Suppose you had a script that downloaded a file and then unzipped it. You can use the subcomponent parameter to identify the source of the error. i.e.:
try
{
//download file
}
catch (Exception e)
{
Dts.Events.FireError(0, "Download File", e.Message, "", 0);
}
try
{
//unzip file
}
catch (Exception e)
{
Dts.Events.FireError(0, "Unzip File", e.Message, "", 0);
}
The logged error could look like this: Unzip File: File does not exist
This could be a helpful pattern for catching generic errors that could apply to different sections of the script.
System::ErrorDescription will only be available in the event handler, but could be handled in a similar way if you scoped the event to particular components.
Leave it as an empty string if you do not need it.
Related
I have following code
IAsyncOperation<bool> trythiswork()
{
bool contentFound{ false };
try
{
auto result = co_await someAsyncFunc();
winrt::check_bool(result)
if (result)
{
contentFound = true;
}
}
catch (...)
{
LOG_CAUGHT_EXCEPTION();
}
co_return contentFound;
}
When the result is false, it fails and throws but catch goes to fail fast and program terminates. How does log function terminate the program? Isn't it supposed to only log the exception? I assumed that I am handling this exception so program won't crash but it is crashing.
So how to throw and catch so that program does not terminate? I do want to throw. And also catch and preferably log the exception as well.
Thanks
The issue can be reproduced using the following code:
IAsyncOperation<bool> someAsyncFunc() { co_return false; }
IAsyncOperation<bool> trythiswork()
{
auto contentFound { false };
try
{
auto result = co_await someAsyncFunc();
winrt::check_bool(result);
// throw std::bad_alloc {};
contentFound = true;
}
catch (...)
{
LOG_CAUGHT_EXCEPTION();
}
co_return contentFound;
}
int main()
{
init_apartment();
auto result = trythiswork().get();
}
As it turns out, everything works as advertised, even if not as intended. When running the code with a debugger attached you will see the following debug output:
The exception %s (0x [trythiswork]
Not very helpful, but it shows that logging itself works. This is followed up by something like
FailFast(1) tid(b230) 8007023E {Application Error}
causing the process to terminate. The WIL only recognizes exceptions of type std::exception, wil::ResultException, and Platform::Exception^. When it handles an unrecognized exception type it will terminate the process by default. This can be verified by commenting out the call to check_bool and instead throwing a standard exception (such as std::bad_alloc). This produces a program that will log exception details, but continue to execute.
The behavior can be customized by registering a callback for custom exception types, giving clients control over translating between custom exception types and HRESULT values. This is useful in cases where WIL needs to interoperate with external library code that uses its own exception types.
For C++/WinRT exception types (based on hresult_error) the WIL already provides error handling helpers that can be enabled (see Integrating with C++/WinRT). To opt into this all you need to do is to #include <wil/cppwinrt.h> before any C++/WinRT headers. When using precompiled headers that's where the #include directive should go.
With that change, the program now works as desired: It logs exception information for exceptions that originate from C++/WinRT, and continues to execute after the exception has been handled.
I have a function which is running in the separate thread. The code which calls this function not waits for result of it.
def sendEmail(email: String): Future[Unit] = {
...
}
def registration: Future[User] = {
...
// I do not want to wait for result of this function, just fire email sending
// in seprate thread and continue
sendEmail(email)
...
// Do another job
}
The problem is that if something went wrong in sendEmail function, I want to see this exception in log file.
Now log file and console output are empty if some exception is thrown there.
Is there a way to log exceptions from that separate thread?
P.S.: I do not want to log exception manually in sendEmail, but force play framework to log it.
In general, you wrap exceptions in the exceptionally block.
In java, it's like :
foobar.thenComposeAsync(arg -> {
sendEmail();
}).exceptionally(throwable -> {
// Do logging
});
I am trying my first features with Behat and I am facing the problem I don't know how to implement expected exceptions.
I found the issue https://github.com/Behat/Behat/issues/140 and robocoder is talking about one possible way, which is used by Behat, too. But it seems that they aren't really handling exceptions.
My point is to achieve forced exception handling. I don't want any construct catching all exceptions and forget them.
One possible way would be:
When <player> transfers <transfer> from his account it should fail with <error>
Implementation
try {
...
} catch (\Exception $ex) {
assertEquals($error, $ex->getMessage());
}
I don't like the scenario description. I want to use the then keyword, e.g.
When <player> transfers <transfer> from his account
Then it should fail with error <error>
This description has the disadvantage I need two methods:
method1($arg1, $arg2) {
// Test the transfer
}
method2($arg1, $arg2) {
// Check if the exception is the right one
}
To be able to check in method2 the exception needs to be stored.
The only possible way I see is to use a try/catch and store it to a variable.
Someone else would catch it and do nothing with it. Nobody will notice, when running the tests.
How can I prevent that exceptions are discarded?
Has anybody else a similar scenario implemented?
Thanks for any hints.
EDIT:
Behat context:
playerTransfer($player, $amount) {
$player->transfer($amount);
}
Method from entity class:
transfer($amount) {
if ($this->getWealth() < $amount) {
throw NotEnoughMoney();
}
...
}
Always try to catch method outcome to context class field, for example:
//inside Behat context class method
try {
$this->outcome = $func();
}
catch(\Exception $ex) {
$this->outcome = $ex;
}
Now when expecting exception at next step just check if $this->outcome is instanceof desired exception with message/code.
I think the problem is in your implementation. Do you check if transfer is successful in "When transfers from his account" ? Do you need to check it ?
Failure test:
When <player> transfers <transfer> from his account
Then I should see error <error>
Successful step:
When <player> transfers <transfer> from his account
Then I should see "transfer successful"
Here's how I successfully did it in a project of mine where I had to repeat a few steps till the condition held true:
/**
* #Given /^I execute some conditions$/
*/
public function executeConditions()
{
$flag = 1;
do {
try {
<steps to be executed till the condition holds true>
$flag=1;
} catch (\Exception $ex) {
$flag = 0;
}
}while ($flag>0);
}
I have a project on WinForms with this code:
AppDomain.CurrentDomain.UnhandledException += CurrentDomainUnhandledException;
private void CurrentDomainUnhandledException(object sender, UnhandledExceptionEventArgs e)
{ }
The e.ExceptionObject contains full StackTrace.
In Win Store project:
this.UnhandledException += (s, e) =>{
{
MarkedUp.AnalyticClient.LogLastChanceException(e);
};
e.Exception.StackTrace is null.
Both exceptions were generated by this code:
int a=0;
....
try
{
int i = 1 / a;
}
catch (Exception exp)
{
throw;
}
Any Ideas?
The reference on MSDN suggests that this is a limitation: http://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.application.unhandledexception
A notable limitation is that the UnhandledException event arguments don’t contain as much detail as the original exception as propagated from app code. Whenever possible, if the app requires specific processing of a certain exception, it’s always better to catch the exception as it propagates, because more detail will be available then. The UnhandledException event arguments expose an exception object through the Exception property. However, the type, message, and stack trace of this exception object are not guaranteed to match those of the original exception that was raised. The event arguments do expose a Message property. In most cases, this will contain the message of the originally raised exception.
Are you running the solution in Debug mode? There seems to be happening something in the App.g.i.cs file when you run the solution in Debug mode. When I run your sample in Release mode the stacktrace is available in the UnhandledException event.
In my test solution it breaks first here:
#if DEBUG && !DISABLE_XAML_GENERATED_BREAK_ON_UNHANDLED_EXCEPTION
UnhandledException += (sender, e) =>
{
if (global::System.Diagnostics.Debugger.IsAttached) global::System.Diagnostics.Debugger.Break();
};
#endif
And after that one it goes to the UnhandledException handler that I have defined in the app.xaml.cs file. In Debug the stacktrace is gone, in Release mode the stacktrace and the exception details are there.
I am running into an extremely strange behavior in Groovy. When I throw an exception from a closure in a Script, the end exception that was thrown was different.
Here are the code and the details:
public class TestDelegate {
def method(Closure closure) {
closure.setResolveStrategy(Closure.DELEGATE_FIRST);
closure.delegate = this;
closure.call();
}
public static void main(String[] args) {
// Make Script from File
File dslFile = new File("src/Script.dsl");
GroovyShell shell = new GroovyShell();
Script dslScript = shell.parse(dslFile);
TestDelegate myDelegate = new TestDelegate();
dslScript.metaClass.methodMissing = {
// will run method(closure)
String name, arguments ->
myDelegate.invokeMethod(name, arguments);
}
dslScript.metaClass.propertyMissing = {
String name ->
println "Will throw error now!"
throw new MyOwnException("errrrror");
}
dslScript.run();
}
}
class MyOwnException extends Exception {
public MyOwnException(String message) {
super(message);
}
}
Script.dsl:
method {
println a;
}
So the plan is that when I run the main() method in TestDelegate, it will run the DSL script, which calls for the method method(). Not finding it in the script, it will invoke methodMissing, which then invokes method() from myDelegate, which in turns invoke the closure, setting the delegate to the testDelegate. So far, so good. Then the closure is supposed to try printing out "a", which is not defined and will thus set off propertyMissing, which will will throw MyOwnException.
When I run the code, however, I get the following output:
Will throw error now!
Exception in thread "main" groovy.lang.MissingPropertyException: No such property: a for class: TestDelegate
Now, it must have reached that catch block, since it printed "Will throw error now!" It must have thrown MyOwnException too! But somewhere along the lines, MyOwnException was converted to MissingPropertyException, and I have no idea why. Does anyone have any idea?
P.S. if I remove closure.setResolveStrategy(Closure.DELEGATE_FIRST) from TestDelegate#method(), the code acts as expected and throws MyOwnException. But I really need the setResolveStrategy(Closure.DELEGATE_FIRST) for my DSL project. And I would prefer to know the root cause of this rather than just removing a line or two and see that it works without understanding why.
I think this is what essentially happens: With a delegate-first resolve strategy, the Groovy runtime first tries to access property a on myDelegate, which results in a MissingPropertyException because no such property exists. Then it tries propertyMissing, which causes a MyOwnException to be thrown. Eventually the runtime gives up and rethrows the first exception encountered (a design decision), which happens to be the MissingPropertyException.
With an owner-first resolve strategy, propertyMissing is consulted first, and hence MyOwnException is eventually rethrown.
Looking at the stack trace and source code underneath should provide more evidence.