I have an MVC website (v5, though I don't think it's related) where I have intentionally introduced an error upon when attempting to establish a database connection (wrong server IP in the connection string). When the user hits the HomeController one dependencies for the constructor is a UserRepository (to get the current user profile data) which depends on a database connection/session to be available. When it's not, the Dependency Resolver can't inject the UserRepository and when that happens it causes an error (as it does with any dependency of any controller), and I get a generic "No parameterless constructor defined for this object". Which is pretty useless.
So I'm trying to use a custom error page to retrieve the inner exception and display it in a friendly manner. (Because this error is happening when trying to acquire the HomeController, it never actually reaches the HandleErrorAttribute, hence the relying on CustomErrors).
So I have an ErrorsController with a series of actions...
Snippet from ErrorsComtroller.cs
public ActionResult Error()
{
return View("Error_500");
}
public ActionResult NotFound()
{
return View("Error_404");
}
Snippet from web.config
<customErrors mode="On">
<error statusCode="404" redirect="~/errors/notfound" />
<error statusCode="500" redirect="~/errors/error" />
</customErrors>
The Error_500 page is pretty basic, it has a model type of HandleErrorInfo, but if it's not present it checks for Exception details using Server.GetLastError(). Problem is, GetLastError() is always null, and I get my custom error page but no additional details beyond my generic feedback of "An unexpected error has occured". After doing some digging I found that the method doesn't work after a redirect, which is the default way the CustomErrors functions. So I changed the web.config to use this line instead...
Snippet from web.config
This way it won't cause a redirect and the GetLastError() should have my exception details about the database connection problem. Thing is, now I get the default ASP.NET error page with this message.
An exception occurred while processing your request. Additionally, another exception occurred while executing the custom error page for the first exception. The request has been terminated.
So I did some more digging using intellitrace, and I see the exception about the database connection. A little farther down I see the error about not having a parameterless constructor on HomeController and then one about encountering an error trying to create the controller of type 'HomeController'. But then I see one that says
Error executing child request for /errors/error
So I navigated directly to that path and the page works fine. But when it's used in customerrors WITH the ResponseRewrite for the redirectmode, it errors out. I put a break line on the first (and only) line of the ErrorsController.Error() action, but it never gets hit. If I substitute the redirect path in the custom errors to a static file it works, but if I change it back to the ~/errors/error it fails again.
Is there a issue when using MVC actions as url's for the CustomErrors when ResponseRewrite is specified?
