Adding |for_view filter to bind permissions for a view name.

djadmin2/permissions.py

@@ -236,9 +236,33 @@ class TemplatePermissionChecker(object):
             except ValueError:
                 return ''
         new_permissions = self.clone()
+        new_permissions._view = None
         new_permissions._model_admin = admin
         return new_permissions
 
+    def bind_view(self, view):
+        '''
+        Return a clone of the permission wrapper with a new view bind to it.
+        '''
+        if isinstance(view, six.string_types):
+            if view not in self.view_name_mapping:
+                return ''
+            view_name = self.view_name_mapping[view]
+            view = getattr(self._model_admin, view_name)
+        # we don't support binding view classes yet, only the name of views
+        # are processed. We have the problem with view classes that we cannot
+        # tell which model admin it was attached to.
+        else:
+            return ''
+        # if view is a class and not instantiated yet, do it!
+        if isinstance(view, type):
+            view = view(
+                request=self._request,
+                **self._model_admin.get_default_view_kwargs())
+        new_permissions = self.clone()
+        new_permissions._view = view
+        return new_permissions
+
     def bind_object(self, obj):
         '''
         Return a clone of the permission wrapper with a new object bind
@@ -248,30 +272,17 @@ class TemplatePermissionChecker(object):
         new_permissions._obj = obj
         return new_permissions
 
-    def get_view_by_name(self, view_name):
-        view_name = self.view_name_mapping[view_name]
-        model_admin = self._model_admin
-        view_class = getattr(model_admin, view_name)
-        view = view_class(
-            request=self._request,
-            **model_admin.get_default_view_kwargs())
-        return view
-
     #########################################
     # interface exposed to the template users
 
     def __getitem__(self, key):
         match = self._has_named_permission_regex.match(key)
         if match:
-            # the key was a has_*_permission, so get the *has permission
-            # wrapper*
+            # the key was a has_*_permission, so bind the correspodning view
             view_name = match.groupdict()['name']
-            if view_name not in self.view_name_mapping:
-                raise KeyError
-            view = self.get_view_by_name(view_name)
-            return self.bind_view(view)
-        # the name might be a named object admin. So get that one and try to
-        # check the permission there for further traversal
+            return self.bind_view(view_name)
+        # the name might be a named object admin. So get that one and bind it
+        # to the permission checking
         try:
             admin_site = self._model_admin.admin
             model_admin = admin_site.get_admin_by_name(key)

djadmin2/templatetags/admin2_tags.py

@@ -45,19 +45,6 @@ def formset_visible_fieldlist(formset):
     return [f.label for f in formset.forms[0].visible_fields()]
 
 
-@register.filter
-def for_object(permissions, obj):
-    """
-    Only useful in the permission handling. This filter binds a new object to
-    the permission handler to check for object-level permissions.
-    """
-    # some permission check has failed earlier, so we don't bother trying to
-    # bind a new object to it.
-    if permissions == '':
-        return permissions
-    return permissions.bind_object(obj)
-
-
 @register.filter
 def for_admin(permissions, admin):
     """
@@ -69,3 +56,30 @@ def for_admin(permissions, admin):
     if permissions == '':
         return permissions
     return permissions.bind_admin(admin)
+
+
+@register.filter
+def for_view(permissions, view):
+    """
+    Only useful in the permission handling. This filter binds a new view to
+    the permission handler to check for view names that are not known during
+    template compile time.
+    """
+    # some permission check has failed earlier, so we don't bother trying to
+    # bind a new admin to it.
+    if permissions == '':
+        return permissions
+    return permissions.bind_view(view)
+
+
+@register.filter
+def for_object(permissions, obj):
+    """
+    Only useful in the permission handling. This filter binds a new object to
+    the permission handler to check for object-level permissions.
+    """
+    # some permission check has failed earlier, so we don't bother trying to
+    # bind a new object to it.
+    if permissions == '':
+        return permissions
+    return permissions.bind_object(obj)

djadmin2/viewmixins.py

@@ -12,6 +12,7 @@ from .utils import admin2_urlname, model_options
 
 
 class PermissionMixin(object):
+    do_not_call_in_templates = True
     permission_classes = (permissions.IsStaffPermission,)
 
     def __init__(self, **kwargs):

example/blog/tests/test_permissions.py

@@ -154,6 +154,86 @@ class TemplatePermissionTest(TestCase):
             context)
         self.assertEqual(result, '')
 
+    def test_view_binding(self):
+        user_admin = djadmin2.default.get_admin_by_name('auth_user')
+        post_admin = djadmin2.default.get_admin_by_name('blog_post')
+        request = self.factory.get(reverse('admin2:auth_user_index'))
+        request.user = self.user
+        permissions = TemplatePermissionChecker(request, user_admin)
+
+        context = {
+            'post_admin': post_admin,
+            'post_add_view': post_admin.create_view,
+            'permissions': permissions,
+        }
+
+        result = self.render(
+            '{% load admin2_tags %}'
+            '{{ permissions|for_view:"add" }}',
+            context)
+        self.assertEqual(result, 'False')
+
+        # view classes are not supported yet
+        result = self.render(
+            '{% load admin2_tags %}'
+            '{{ permissions|for_view:post_add_view }}',
+            context)
+        self.assertEqual(result, '')
+
+        result = self.render(
+            '{% load admin2_tags %}'
+            # user add permission
+            '{{ permissions.has_add_permission }}'
+            '{% with permissions|for_admin:"blog_post"|for_view:"add" as post_add_perm %}'
+                # post add permission
+                '{{ post_add_perm }}'
+            '{% endwith %}',
+            context)
+        self.assertEqual(result, 'FalseFalse')
+
+        post_add_permission = Permission.objects.get(
+            content_type__app_label='blog',
+            content_type__model='post',
+            codename='add_post')
+        self.user.user_permissions.add(post_add_permission)
+        user_change_permission = Permission.objects.get(
+            content_type__app_label='auth',
+            content_type__model='user',
+            codename='change_user')
+        self.user.user_permissions.add(user_change_permission)
+
+        # invalidate the users permission cache
+        if hasattr(self.user, '_perm_cache'):
+            del self.user._perm_cache
+
+        result = self.render(
+            '{% load admin2_tags %}'
+            # user add permission
+            '{{ permissions.has_add_permission }}'
+            '{% with permissions|for_admin:"blog_post"|for_view:"add" as post_add_perm %}'
+                # post add permission
+                '{{ post_add_perm }}'
+            '{% endwith %}'
+            # user change permission
+            '{{ permissions|for_view:"change" }}',
+            context)
+        self.assertEqual(result, 'FalseTrueTrue')
+
+        # giving a string (the name of the view) also works
+        result = self.render(
+            '{% load admin2_tags %}'
+            '{% with permissions|for_view:"change" as user_change_perm %}'
+                '1{{ user_change_perm }}'
+                '2{{ user_change_perm|for_view:"add" }}'
+                # this shouldn't return True or False but '' since the
+                # previously bound change view doesn't belong to the newly
+                # bound blog_post admin
+                '3{{ user_change_perm|for_admin:"blog_post" }}'
+                '4{{ user_change_perm|for_admin:"blog_post"|for_view:"add" }}'
+            '{% endwith %}',
+            context)
+        self.assertEqual(result, '1True2False34True')
+
     def test_object_level_permission(self):
         model_admin = ModelAdmin2(Post, djadmin2.default)
         request = self.factory.get(reverse('admin2:blog_post_index'))