Added decorator to be used with views, yay

src/authority/decorators.py

@@ -0,0 +1,47 @@
+import inspect
+from decorator import decorator
+from django.core.exceptions import PermissionDenied
+from django.http import HttpResponseForbidden, HttpResponseRedirect, Http404
+from django.utils.http import urlquote
+from django.db.models import Model, get_model
+from django.shortcuts import get_object_or_404
+from django.conf import settings
+from django.contrib.auth.decorators import user_passes_test
+from django.contrib.auth import REDIRECT_FIELD_NAME
+
+from authority import permissions
+
+def permission_required(perm, *args, **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', None)
+    if not login_url:
+        login_url = getattr(settings, 'LOGIN_URL', '/')
+    redirect_field_name = kwargs.pop('redirect_field_name', REDIRECT_FIELD_NAME)
+    model_lookups = args
+    def _permission_required(view_func, request, *args, **kwargs):
+        objs = []
+        # model_lookups = [('flatpages.flatpage', 'url__contains')]
+        for i, arguments in enumerate(model_lookups):
+            model, lookup = arguments
+            if isinstance(model, basestring):
+                model_class = 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)
+            objs.append(get_object_or_404(model_class, **{lookup: args[i]}))
+        check = permissions.registry.get_check(request.user, perm)
+        if check is not None:
+            if check(*objs):
+                return view_func(request, *args, **kwargs)
+        #return HttpResponseForbidden("Permission")
+        raise PermissionDenied()
+    return decorator(_permission_required)