Django 2.2 breaks previously working views/urls

Question

Decided to take out Django 2.2 for a spin (project is currently running 2.1.8) and now I can\'t even get the server to start. I have been maintaining this project for nearly

Answer 1

It seems the custom error handlers are the cause of it.

In Django 2.1 I had a custom handler for a 500 Error error like this:

def error_500_view(request, exception):
    return render(request,'500.html')

But in Django 2.2 it seems that the 500 Error handler only takes 1 argument, so I changed to:

def error_500_view(request):
    return render(request,'500.html')

And everything is working normal again.

So make sure your 404 Error handler is something like:

def notfound(request, exception):
    return render(request,'400.html')