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迁移报错

# python manage.py makemigrations
SystemCheckError: System check identified some issues:

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

Django2.1版本在2.2版本上也没发生大变化

# django/views/defaults.py

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/')
        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': 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
        template = Engine().from_string(
            '<h1>Not Found</h1>'
            '<p>The requested URL {{ request_path }} was not found on this server.</p>')
        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('<h1>Server Error (500)</h1>', 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('<h1>Bad Request (400)</h1>', 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('<h1>403 Forbidden</h1>', content_type='text/html')
    return HttpResponseForbidden(
        template.render(request=request, context={'exception': str(exception)})
    )

# django/conf/urls/__init__.py

from django.urls import include, re_path
from django.views import defaults

__all__ = ['handler400', 'handler403', 'handler404', 'handler500', 'include', 'url']

handler400 = defaults.bad_request
handler403 = defaults.permission_denied
handler404 = defaults.page_not_found
handler500 = defaults.server_error


def url(regex, view, kwargs=None, name=None):
    return re_path(regex, view, kwargs, name)

确认问题，检查是全局403、404的问题

少了一个exception参数，意思是

来自异常的消息，该异常触发404(如果有的话)或异常类名

# 全局403、404、500错误自定义页面显示
def page_not_found(request, exception=404):
    return render(request, '404.html')


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


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


# 定义错误跳转页面
handler403 = permission_denied
handler404 = page_not_found
handler500 = page_error

但上一个版本就是正常的，那，我也不知道了~