Django2.1.8升级到2.2.3自定义错误界面报错handler400，handler403，handler404，handler500设置失败问题

 

网上错误解决方法：

1.配置settings

配置tamplates文件路径、关闭Debug、配置allowrd_hosts

2.编写视图

from django.shortcuts import render


def page_not_found(request):
    return render(request, '404.html')


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


def permission_denied(request):
    return render(request, '403.html')

3.配置url

...
from myapp.views import *

handler403 = permission_denied
handler404 = page_not_found
handler500 = page_error
...

注意了，当你按照上面的方法来解决时，发现会报错

Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py", line 865, in run
    self._target(*self._args, **self._kwargs)
  File "/Users/darkmoon/PycharmProjects/LDjango1/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 54, in wrapper
    fn(*args, **kwargs)
  File "/Users/darkmoon/PycharmProjects/LDjango1/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 117, in inner_run
    self.check(display_num_errors=True)
  File "/Users/darkmoon/PycharmProjects/LDjango1/venv/lib/python3.7/site-packages/django/core/management/base.py", line 436, in check
    raise SystemCheckError(msg)
django.core.management.base.SystemCheckError: SystemCheckError: System check identified some issues:

ERRORS:
?: (urls.E007) The custom handler400 view 'mysite.views.bad_request' does not take the correct number of arguments (request, exception).
?: (urls.E007) The custom handler403 view 'mysite.views.permission_denied' does not take the correct number of arguments (request, exception).
?: (urls.E007) The custom handler404 view 'mysite.views.page_not_found' does not take the correct number of arguments (request, exception).

System check identified 3 issues (0 silenced).

仔细研究发现，视图函数缺少了参数，咋们先看看默认错误视图的源代码：

from urllib.parse import quote

from django.http import (
    HttpResponseBadRequest, HttpResponseForbidden, HttpResponseNotFound,
    HttpResponseServerError,
)
from django.template import Context, Engine, TemplateDoesNotExist, loader
from django.views.decorators.csrf import requires_csrf_token

ERROR_404_TEMPLATE_NAME = '404.html'
ERROR_403_TEMPLATE_NAME = '403.html'
ERROR_400_TEMPLATE_NAME = '400.html'
ERROR_500_TEMPLATE_NAME = '500.html'


# This can be called when CsrfViewMiddleware.process_view has not run,
# therefore need @requires_csrf_token in case the template needs
# {% csrf_token %}.
@requires_csrf_token
def page_not_found(request, exception, template_name=ERROR_404_TEMPLATE_NAME):
    """
    Default 404 handler.

    Templates: :template:`404.html`
    Context:
        request_path
            The path of the requested URL (e.g., '/app/pages/bad_page/'). It's
            quoted to prevent a content injection attack.
        exception
            The message from the exception which triggered the 404 (if one was
            supplied), or the exception class name
    """
    exception_repr = exception.__class__.__name__
    # Try to get an "interesting" exception message, if any (and not the ugly
    # Resolver404 dictionary)
    try:
        message = exception.args[0]
    except (AttributeError, IndexError):
        pass
    else:
        if isinstance(message, str):
            exception_repr = message
    context = {
        'request_path': quote(request.path),
        'exception': exception_repr,
    }
    try:
        template = loader.get_template(template_name)
        body = template.render(context, request)
        content_type = None             # Django will use DEFAULT_CONTENT_TYPE
    except TemplateDoesNotExist:
        if template_name != ERROR_404_TEMPLATE_NAME:
            # Reraise if it's a missing custom template.
            raise
        # Render template (even though there are no substitutions) to allow
        # inspecting the context in tests.
        template = Engine().from_string(
            '
Not Found
'
            '
The requested resource was not found on this server.
')
        body = template.render(Context(context))
        content_type = 'text/html'
    return HttpResponseNotFound(body, content_type=content_type)


@requires_csrf_token
def server_error(request, template_name=ERROR_500_TEMPLATE_NAME):
    """
    500 error handler.

    Templates: :template:`500.html`
    Context: None
    """
    try:
        template = loader.get_template(template_name)
    except TemplateDoesNotExist:
        if template_name != ERROR_500_TEMPLATE_NAME:
            # Reraise if it's a missing custom template.
            raise
        return HttpResponseServerError('
Server Error (500)
', content_type='text/html')
    return HttpResponseServerError(template.render())


@requires_csrf_token
def bad_request(request, exception, template_name=ERROR_400_TEMPLATE_NAME):
    """
    400 error handler.

    Templates: :template:`400.html`
    Context: None
    """
    try:
        template = loader.get_template(template_name)
    except TemplateDoesNotExist:
        if template_name != ERROR_400_TEMPLATE_NAME:
            # Reraise if it's a missing custom template.
            raise
        return HttpResponseBadRequest('
Bad Request (400)
', content_type='text/html')
    # No exception content is passed to the template, to not disclose any sensitive information.
    return HttpResponseBadRequest(template.render())


# This can be called when CsrfViewMiddleware.process_view has not run,
# therefore need @requires_csrf_token in case the template needs
# {% csrf_token %}.
@requires_csrf_token
def permission_denied(request, exception, template_name=ERROR_403_TEMPLATE_NAME):
    """
    Permission denied (403) handler.

    Templates: :template:`403.html`
    Context: None

    If the template does not exist, an Http403 response containing the text
    "403 Forbidden" (as per RFC 7231) will be returned.
    """
    try:
        template = loader.get_template(template_name)
    except TemplateDoesNotExist:
        if template_name != ERROR_403_TEMPLATE_NAME:
            # Reraise if it's a missing custom template.
            raise
        return HttpResponseForbidden('
403 Forbidden
', content_type='text/html')
    return HttpResponseForbidden(
        template.render(request=request, context={'exception': str(exception)})
    )

我们发现，咋们自定义的视图缺少了exception,我们自己给补上就可以正常运行了。

def bad_request(request, exception, template_name='400.html'):
    return render(request, template_name)


def permission_denied(request, exception, template_name='403.html'):
    return render(request, template_name)


def page_not_found(request, exception, template_name='404.html'):
    return render(request, template_name)


def server_error(request, template_name='500.html'):
    return render(request, template_name)

此时可以正常运行了！！！