django-authority/authority/decorators.py
2020-02-07 10:50:47 +01:00

79 lines
3.3 KiB
Python

import inspect
from django.http import HttpResponseRedirect
from django.utils.http import urlquote
from django.utils.functional import wraps
from django.utils.six import string_types
from django.db.models import Model
from django.apps import apps
from django.shortcuts import get_object_or_404
from django.conf import settings
from django.contrib.auth import REDIRECT_FIELD_NAME
from authority.utils import get_check
from authority.views import permission_denied
def permission_required(perm, *lookup_variables, **kwargs):
"""
Decorator for views that checks whether a user has a particular permission
enabled, redirecting to the log-in page if necessary.
"""
login_url = kwargs.pop("login_url", settings.LOGIN_URL)
redirect_field_name = kwargs.pop("redirect_field_name", REDIRECT_FIELD_NAME)
redirect_to_login = kwargs.pop("redirect_to_login", True)
def decorate(view_func):
def decorated(request, *args, **kwargs):
if request.user.is_authenticated:
params = []
for lookup_variable in lookup_variables:
if isinstance(lookup_variable, string_types):
value = kwargs.get(lookup_variable, None)
if value is None:
continue
params.append(value)
elif isinstance(lookup_variable, (tuple, list)):
model, lookup, varname = lookup_variable
value = kwargs.get(varname, None)
if value is None:
continue
if isinstance(model, string_types):
model_class = apps.get_model(*model.split("."))
else:
model_class = model
if model_class is None:
raise ValueError(
"The given argument '%s' is not a valid model." % model
)
if inspect.isclass(model_class) and not issubclass(
model_class, Model
):
raise ValueError(
"The argument %s needs to be a model." % model
)
obj = get_object_or_404(model_class, **{lookup: value})
params.append(obj)
check = get_check(request.user, perm)
granted = False
if check is not None:
granted = check(*params)
if granted or request.user.has_perm(perm):
return view_func(request, *args, **kwargs)
if redirect_to_login:
path = urlquote(request.get_full_path())
tup = login_url, redirect_field_name, path
return HttpResponseRedirect("%s?%s=%s" % tup)
return permission_denied(request)
return wraps(view_func)(decorated)
return decorate
def permission_required_or_403(perm, *args, **kwargs):
"""
Decorator that wraps the permission_required decorator and returns a
permission denied (403) page instead of redirecting to the login URL.
"""
kwargs["redirect_to_login"] = False
return permission_required(perm, *args, **kwargs)