Django HTTP 500 Error

Question

I am creating a custom HTTP 500 error template. Why is it Django shows it when i raise an exception and not when I return HttpResponseServerError (I just get the default browser 500 error)? I find this behaviour strange...

Answer 1

The HttpResponseServerError inherits from HttpResponse and is actually quite simple:

class HttpResponseServerError(HttpResponse):
    status_code = 500

So let's look at the HttpResponse constructor:

def __init__(self, content='', *args, **kwargs):
    super(HttpResponse, self).__init__(*args, **kwargs)
    # Content is a bytestring. See the `content` property methods.
    self.content = content

As you can see by default content is empty.

Now, let's take a look at how it is called by Django itself (an excerpt from django.views.defaults):

def server_error(request, template_name='500.html'):
    """
    500 error handler.

    Templates: :template:`500.html`
    Context: None
    """
    try:
        template = loader.get_template(template_name)
    except TemplateDoesNotExist:
        return http.HttpResponseServerError('<h1>Server Error (500)</h1>')
    return http.HttpResponseServerError(template.render(Context({})))

As you can see when you produce a server error, the template named 500.html is used, but when you simply return HttpResponseServerError the content is empty and the browser falls back to it's default page.

Answer 2

Put this below in the urls.py.

#handle the errors    
from django.utils.functional import curry
from django.views.defaults import *

handler500 = curry(server_error, template_name='500.html')

Put 500.html in your templates. Just as simple like that.

Answer 3

Have you tried with another browser ? Is your custom error page larger than 512 bytes ? It seems some browsers (including Chrome) replace errors page with their own when the server's answer is shorter than 512 bytes.

Answer 4

As of Django 2+ all you need to do is put the corresponding error templates in your base templates folder. Django will automatically render them before rendering the default.

https://docs.djangoproject.com/en/2.0/ref/views/#error-views

In your case just drop your template '500.html' (or '404.html') into /templates