troggle-unchained/core/middleware.py

73 lines
2.8 KiB
Python

from django import http
from django.conf import settings
from django.urls import Resolver404, resolve, reverse
"""Non-standard django middleware is loaded from this file.
"""
todo = '''SmartAppendSlashMiddleware(object) Not Working.
It needs re-writing to be compatible with Django v2.0 and later
'''
class SmartAppendSlashMiddleware(object):
"""
"SmartAppendSlash" middleware for taking care of URL rewriting.
This middleware appends a missing slash, if:
* the SMART_APPEND_SLASH setting is True
* the URL without the slash does not exist
* the URL with an appended slash does exist.
Otherwise it won't touch the URL.
"""
def process_request(self, request):
'''Called for every url so return as quickly as possible
Append a slash if SMART_APPEND_SLASH is set, the resulting URL resolves and it doesn't without the /
'''
if not settings.SMART_APPEND_SLASH:
return None
if request.path.endswith('/'):
return None
if request.path.endswith('_edit'):
return None
host = http.HttpRequest.get_host(request)
old_url = [host, request.path]
if _resolves(old_url[1]):
return None
# So: it does not resolve according to our criteria, i.e. _edit doesn't count
new_url = old_url[:]
new_url[1] = new_url[1] + '/'
if not _resolves(new_url[1]):
return None
else:
if settings.DEBUG and request.method == 'POST':
# replace this exception with a redirect to an error page
raise RuntimeError(f"You called this URL via POST, but the URL doesn't end in a slash and you have SMART_APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to {new_url[0]}{new_url[1]} (note the trailing slash), or set SMART_APPEND_SLASH=False in your Django settings.")
if new_url != old_url:
# Redirect
if new_url[0]:
newurl = f"{request.is_secure() and 'https' or 'http'}://{new_url[0]}{new_url[1]}"
else:
newurl = new_url[1]
if request.GET:
newurl += '?' + request.GET.urlencode()
return http.HttpResponsePermanentRedirect(newurl)
return None
def _resolves(url):
try:
# If the URL does not resolve, the function raises a Resolver404 exception (a subclass of Http404)
match = resolve(url)
# this will ALWAYS be resolved by expopages because it will produce pagenotfound if not the thing asked for
# so handle this in expopages, not in middleware
return True
except Resolver404:
return False
except:
print(url)
raise