django.urls.exceptions Resolver404 Django Code Examples

Resolver404 (source code) is a Django exception that is raised when the path passed to the resolve function does not map to a view that is specified in your project's file.

Example 1 from django-cms

django-cms (project website) is a Python-based content management system (CMS) library for use with Django web apps that is open sourced under the BSD 3-Clause "New" license.

django-cms / cms /

# -*- coding: utf-8 -*-
from django.conf import settings
from django.http import Http404
from django.shortcuts import render
from django.template.response import TemplateResponse
from django.urls import Resolver404, resolve, reverse

from cms import __version__
from import set_page_cache
from cms.models import Page
from cms.utils.conf import get_cms_setting
from import get_page_template_from_request
from cms.utils.page_permissions import user_can_change_page, user_can_view_page

def render_page(request, page, current_language, slug):
    Renders a page
    context = {}
    context['lang'] = current_language
    context['current_page'] = page
    context['has_change_permissions'] = user_can_change_page(request.user, page)
    context['has_view_permissions'] = user_can_view_page(request.user, page)

    if not context['has_view_permissions']:
        return _handle_no_page(request)

    template = get_page_template_from_request(request)
    response = TemplateResponse(request, template, context)

    # Add headers for X Frame Options - this really should be changed upon moving to class based views
    xframe_options = page.get_xframe_options()
    # xframe_options can be None if there's no xframe information on the page
    # (eg. a top-level page which has xframe options set to "inherit")
    if xframe_options == Page.X_FRAME_OPTIONS_INHERIT or xframe_options is None:
        # This is when we defer to django's own clickjacking handling
        return response

    # We want to prevent django setting this in their middlewear
    response.xframe_options_exempt = True

    if xframe_options == Page.X_FRAME_OPTIONS_ALLOW:
        # Do nothing, allowed is no header.
        return response
    elif xframe_options == Page.X_FRAME_OPTIONS_SAMEORIGIN:
        response['X-Frame-Options'] = 'SAMEORIGIN'
    elif xframe_options == Page.X_FRAME_OPTIONS_DENY:
        response['X-Frame-Options'] = 'DENY'
    return response

def render_object_structure(request, obj):
    context = {
        'object': obj,
        'cms_toolbar': request.toolbar,
    return render(request, 'cms/toolbar/structure.html', context)

def _handle_no_page(request):
        #add a $ to the end of the url (does not match on the cms anymore)
        resolve('%s$' % request.path)
    except Resolver404 as e:
        # raise a django http 404 page
        exc = Http404(dict(path=request.path, tried=e.args[0]['tried']))
        raise exc
    raise Http404('CMS Page not found: %s' % request.path)

def _render_welcome_page(request):
    context = {
        'cms_version': __version__,
        'cms_edit_on': get_cms_setting('CMS_TOOLBAR_URL__EDIT_ON'),
        'django_debug': settings.DEBUG,
        'next_url': reverse('pages-root'),
    return TemplateResponse(request, "cms/welcome.html", context)

Example 2 from django-wiki

django-wiki (project documentation, demo, and PyPI page) is a wiki system code library for Django projects that makes it easier to create user-editable content. The project aims to provide necessary core features and then have an easy plugin format for additional features, rather than having every exhaustive feature built into the core system. django-wiki is a rewrite of an earlier now-defunct project named django-simplewiki.

The code for django-wiki is provided as open source under the GNU General Public License 3.0.

django-wiki / src/ wiki /

__all__ = [

from datetime import timedelta

from django import forms
from django.apps import apps
from django.contrib.auth import get_user_model
from django.core import validators
from django.core.validators import RegexValidator
from django.forms.widgets import HiddenInput
from django.shortcuts import get_object_or_404
from django.urls import Resolver404, resolve
from django.utils import timezone
from django.utils.safestring import mark_safe
from django.utils.translation import gettext, gettext_lazy as _, pgettext_lazy
from wiki import models
from wiki.conf import settings
from wiki.core import permissions
from wiki.core.diff import simple_merge
from wiki.core.plugins.base import PluginSettingsFormMixin
from wiki.editors import getEditor

from .forms_account_handling import UserCreationForm, UserUpdateForm

validate_slug_numbers = RegexValidator(
    _("A 'slug' cannot consist solely of numbers."),

class WikiSlugField(forms.CharField):
    In future versions of Django, we might be able to define this field as
    the default field directly on the model. For now, it's used in CreateForm.

    default_validators = [validators.validate_slug, validate_slug_numbers]

    def __init__(self, *args, **kwargs):
        self.allow_unicode = kwargs.pop('allow_unicode', False)
        if self.allow_unicode:
            self.default_validators = [
        super().__init__(*args, **kwargs)

def _clean_slug(slug, urlpath):
    if slug.startswith("_"):
        raise forms.ValidationError(
            gettext('A slug may not begin with an underscore.'))
    if slug == 'admin':
        raise forms.ValidationError(
            gettext("'admin' is not a permitted slug name."))

    if settings.URL_CASE_SENSITIVE:
        already_existing_slug = models.URLPath.objects.filter(
        slug = slug.lower()
        already_existing_slug = models.URLPath.objects.filter(
    if already_existing_slug:
        already_urlpath = already_existing_slug[0]
        if already_urlpath.article and already_urlpath.article.current_revision.deleted:
            raise forms.ValidationError(
                gettext('A deleted article with slug "%s" already exists.') %
            raise forms.ValidationError(
                gettext('A slug named "%s" already exists.') %

            # Fail validation if URL resolves to non-wiki app
            match = resolve(urlpath.path + '/' + slug + '/')
            if match.app_name != 'wiki':
                raise forms.ValidationError(
                    gettext('This slug conflicts with an existing URL.'))
        except Resolver404:

    return slug

## ... source file continues with no further relevant examples ...
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