--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/soc/logic/helper/access.py	Thu Oct 09 23:38:27 2008 +0000
@@ -0,0 +1,173 @@
+#!/usr/bin/python2.5
+#
+# Copyright 2008 the Melange authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Access control helper.
+
+The functions in this module can be used to check access control
+related requirements. When the specified required conditions are not
+met, an exception is raised. This exception contains a views that
+either prompts for authentication, or informs the user that they
+do not meet the required criteria.
+"""
+
+__authors__ = [
+  '"Todd Larsen" <tlarsen@google.com>',
+  '"Sverre Rabbelier" <sverre@rabbelier.nl>',
+  '"Pawel Solyga" <pawel.solyga@gmail.com>',
+  ]
+
+
+from google.appengine.api import users
+from django.utils.translation import ugettext_lazy
+
+import soc.logic.host
+import soc.logic.out_of_band
+
+from soc.views.simple import requestLogin
+from soc.logic.site import id_user
+
+
+DEF_LOGIN_TMPL = 'soc/login.html'
+
+DEF_LOGIN_MSG_FMT = ugettext_lazy(
+  'Please <a href="%(sign_in)s">sign in</a> to continue.')
+
+DEF_NO_USER_LOGIN_MSG_FMT = ugettext_lazy(
+  'Please create <a href="/user/profile">User Profile</a>'
+  ' in order to view this page.')
+
+DEF_DEV_LOGOUT_LOGIN_MSG_FMT = (
+  'Please <a href="%%(sign_out)s">sign out</a>'
+  ' and <a href="%%(sign_in)s">sign in</a>'
+  ' again as %(role)s to view this page.')
+
+
+def checkIsLoggedIn(request):
+  """Returns an alternate HTTP response if Google Account is not logged in.
+
+  Args:
+    request: A Django HTTP request
+
+   Raises:
+     AccessViolationResponse: If the required authorization is not met.
+
+  Returns:
+    None if the user is logged in, or a subclass of
+    django.http.HttpResponse which contains the alternate response
+    that should be returned by the calling view.
+  """
+
+  if users.get_current_user():
+    return
+
+  login_request = requestLogin(request, DEF_LOGIN_TMPL,
+                      login_message_fmt=DEF_LOGIN_MSG_FMT)
+
+  raise soc.logic.out_of_band.AccessViolationResponse(login_request)
+
+
+def checkIsUser(request):
+  """Returns an alternate HTTP response if Google Account has no User entity.
+
+  Args:
+    request: A Django HTTP request
+
+   Raises:
+     AccessViolationResponse: If the required authorization is not met.
+
+  Returns:
+    None if User exists for id, or a subclass of
+    django.http.HttpResponse which contains the alternate response
+    should be returned by the calling view.
+  """
+
+  checkIsLoggedIn(request)
+
+  id = users.get_current_user()
+  user = id_user.getUserFromId(id)
+
+  if user:
+    return
+
+  login_request = requestLogin(request, DEF_LOGIN_TMPL,
+                      login_message_fmt=DEF_NO_USER_LOGIN_MSG_FMT)
+
+  raise soc.logic.out_of_band.AccessViolationResponse(login_request)
+
+
+def checkIsDeveloper(request):
+  """Returns an alternate HTTP response if Google Account is not a Developer.
+
+  Args:
+    request: A Django HTTP request
+
+   Raises:
+     AccessViolationResponse: If the required authorization is not met.
+
+  Returns:
+    None if id is logged in and logged-in user is a Developer, or a
+    subclass of django.http.HttpResponse which contains the alternate
+    response should be returned by the calling view.
+  """
+
+  checkIsUser(request)
+
+  id = users.get_current_user()
+
+  if id_user.isIdDeveloper(id=id):
+    return None
+
+  login_message_fmt = DEF_DEV_LOGOUT_LOGIN_MSG_FMT % {
+      'role' : 'a site developer ',
+      }
+
+  login_request = requestLogin(request, DEF_LOGIN_TMPL,
+                      login_message_fmt=login_message_fmt)
+
+  raise soc.logic.out_of_band.AccessViolationResponse(login_request)
+
+
+def checkIsHost(request, program):
+  """Returns an alternate HTTP response if Google Account has no Host entity for the specified program.
+
+  Args:
+    request: A Django HTTP request
+
+   Raises:
+     AccessViolationResponse: If the required authorization is not met.
+
+  Returns:
+    None if Host exists for the specified program, or a subclass of
+    django.http.HttpResponse which contains the alternate response
+    should be returned by the calling view.
+  """
+
+  checkIsUser(request)
+
+  id = users.get_current_user()
+  host = soc.logic.host.getHostFromProgram(id, program)
+
+  if host:
+    return
+
+  login_message_fmt = DEF_DEV_LOGOUT_LOGIN_MSG_FMT % {
+      'role' : 'a host for this program',
+      }
+
+  login_request = requestLogin(request, DEF_LOGIN_TMPL,
+                      login_message_fmt=login_message_fmt)
+
+  raise soc.logic.out_of_band.AccessViolationResponse(login_request)