I have setup UseStatusCodePagesWithReExecute in asp.netcore website and it works fine.
I'm now trying to manually throw an error and I would like UseStatusCodePagesWithReExecute to catch it automatically but not as a 500 but as a 401 !
What type of exception should I throw?
If it's not possible, I guess I will have to create my custom middleware. In that case, how do I redirect from it in case I have this exception?
Related
I am running one MVC application where i found one exception in specific method. I will provide here complete details about it.
I am loading some third party grid control from view. to load it i used below code:
#{Html.RenderAction("MasterGridAction", "MyController");}
Now when i access this report from development then this view load and it hits this action method where i used some piece of code there it is throwing error, To catch the error i used try catch block in the method where in catch section i used below code to throw the actual exception like below:
catch (Exception ex)
{
System.Runtime.ExceptionServices.ExceptionDispatchInfo.Capture(ex).Throw(); throw;
}
When exception get catched it sends this to the Application_Error method in global.asax page where i used below code to find out the actual exception like below:
void Application_Error(object sender, EventArgs e)
{
HttpServerUtility server = HttpContext.Current.Server;
if (server.GetLastError() != null)
{
Exception exception = server.GetLastError();
if (exception.GetBaseException() != null)
{
exception = exception.GetBaseException();
ExceptionType(server, exception);
}
else
{
ExceptionType(server, exception);
}
}
}
In this ExceptionType method i get the exception stack and log to the file using "Log4Net". After logging to the file i could see the exception in notepad like below:
Object reference not set to an instance of an object.
Source File: /MyController/MasterGridAction
Stack Trace:
at 3D.Controllers.MyController.MasterGridAction() in D:\MyUser\3D_MVC\Application\3D_OnlyRelease\3D\Controllers\MyController.cs:line 405
--- End of stack trace from previous location where exception was thrown ---
As we can see in above exception it is clearly shown the line number also where this exception get caught.
But once i host this application in IIS server and access the same page then i could see the logged file
There it shows exception like below:
Exception Message: Object reference not set to an instance of an object.
Stack Trace: at 3D.Controllers.MyController.MasterGridAction()
--- End of stack trace from previous location where exception was thrown ---
As you can see the logged exception of IIS server is not having much information when compare to other exception details.
Am i missing anything there to get the complete exception when host in IIS?
Please suggest.
As you can see the logged exception of IIS server is not having much information when compare to other exception details.
This could be because you don't include the PDB files in production.
It might not be a great idea to include them, since that way one can reverse engineer you app with more precision if they hack your server, but it is up to you to decide. I have seen organizations that include them in their production environments.
Try publishing and deploying on a test environment with and without the PDB files to verify this.
I am wondering what is the difference between throwing just Exception and throwing a specific Exception such as NullPointer Exception.
To my current knowledge an Exception should be able to catch any type of exception where as using a specific Exception expects that only that exception type can be thrown.
Example:
void test(String testString) throws Exception;
vs
void test(String testString) throws NullPointerException;
If this is correct than to me it makes sense to just always throw Exception and to never name a specific exception. Am I missing something important here? Does it at the very least effect performance at all? A lot of people are looking between throwing and catching exceptions but nobody asks this very basic question.
I do not see a benefit of throwing any exception except Exception.
To start off, Exception is a base type of every Exception. Just like object is for everything.
By throwing a specific Exception you provide more information to the consumer of what has happened.
Imagine scenario where you get a plain Exception without a message, consumer is lost. When for example framework throws a NullReferenceException, then you are aware of a fact that one of your objects does not have a reference which it was trying to access.
This is how you can chain exceptions and make use of their types:
try
{
throw new NotImplementedException();
}
catch(NullReferenceException ex)
{
// Logic for NullReference exception if needed.
}
catch(NotImplementedException ex)
{
// This will be executed.
}
catch(Exception ex)
{
// Will catch every exception.
}
There are at least two reasons why you would want to throw a specific kind of exception:
If a program fails with an exception, you will have more information with which to determine what went wrong. Compare seeing Exception with FileNotFoundException. The latter clearly gives you more information.
In some cases, the code will want to catch certain kinds of exceptions. For example, when working with serial ports, you might want to catch and handle a TimeoutException differently from a NullReferenceException.
The NullPointerException you mentioned is a very good example from the regular Exception because it is a subclass of RuntimeException. Any throwing of (a subclass of) RuntimeException does not have to be caught or declared.
Any other (=not a subclass of RuntimeException) Exception has to be handled in your code by either a try/catch block or a throws declaration. Otherwise, your code will not even compile! That forces you as a developer to handle errors that might pop up.
As for why using different Exception types is useful, consider the following simple example that uses multiple catch statements:
void doDBStuff(){
try {
performStatement(someStatement);
} catch(SQLException e){
//invalid SQL syntax, something is broken
} catch(AuthenticationException e){
//invalid user credentials for the db, inform the user to change these values
}
In this example, two different exceptions end up in two different catch blocks which lets you handle these errors differently.
It's a best practice to throw specific exceptions, instead of a generic one. This is because the caller might want to treat the exceptions differently, for example in a WebApi you might want to return a Bad Request response (400) for a ArgumentNullException, but you might want to return a different result for other types of exceptions. For example you might actually throw a custom NotFoundException and then the controller would catch it and return a Not Found response (404) instead.
Basically if you throw specific exceptions you are allowing the consumer code to handle the different exception scenarios the way they want.
I am wondering how I can tell camel to redeliver my message based on business logic.
My route is calling a soap endpoint and, depending on the message returned by the server I need to schedule a retry in a few seconds.
Basically, I have this kind of error handling configured :
onException(Throwable.class)
.handled(true)
.processRef("exceptionHandler")
.redeliveryDelay(5000)
.maximumRedeliveries(1)
.to("file://
My exceptionHandler check if the exception is a SOAP Fault, unmarshal it and depending on the content I need to schedule the retry.
Is there anyway of doing that within camel ?
Well, in the end, here is my solution :
from("...")
.doTry()
.to("...")
.doCatch(Exception.class)
.beanRef("handleException")
.end()
.beanRef("handleRegularResponse");
The processor handleException handles the exception, try to understand the issue and then throw a more precise exception. In my case, it can throw 2 types of exception : FunctionalException that do not need to redeliver, and a TechnicalException that I will try to redeliver in a few minutes.
I just have then to declare an error handler for this specific exception :
onException(TechnicalException.class)
.handled(true)
.redeliveryPolicyRef("...")
.useOriginalMessage();
HIH
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 question about kohana exceptions.
I have a site that I want to put in production, and I don't want the exceptions to be simply thrown (like they are now), but I want to redirect the user to another page in case of an exception occured.
I use kohana 3, and I wonder: how can I catch an exception and redirect the user to another page if an exception happens:
example of code:
instead of
if ( ! $sale->loaded())
{
throw new Kohana_Request_Exception('Sale not found.');
}
I want: something like: page not found.
thank you!
What you'll need to do is register your own exception handler.
Take a look at the Error Handling documentation for an idea on what to do. Basically, you can capture any type of exception you want and do something specific with it (such as display a 404 page).