Moved RequestSite and get_current_site.

Following the app-loading refactor, these objects must live outside of
django.contrib.sites.models because they must be available without
importing the django.contrib.sites.models module when
django.contrib.sites isn't installed.

Refs #21680. Thanks Carl and Loic for reporting this issue.

django/contrib/auth/forms.py

@@ -16,7 +16,7 @@ from django.contrib.auth import authenticate, get_user_model
 from django.contrib.auth.models import User
 from django.contrib.auth.hashers import UNUSABLE_PASSWORD_PREFIX, identify_hasher
 from django.contrib.auth.tokens import default_token_generator
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 
 
 UNMASKED_DIGITS_TO_SHOW = 6

django/contrib/auth/tests/test_views.py

@@ -4,7 +4,8 @@ import os
 import re
 
 from django.conf import global_settings, settings
-from django.contrib.sites.models import Site, RequestSite
+from django.contrib.sites.models import Site
+from django.contrib.sites.requests import RequestSite
 from django.contrib.admin.models import LogEntry
 from django.contrib.auth.models import User
 from django.core import mail

django/contrib/auth/views.py

@@ -15,7 +15,7 @@ from django.contrib.auth import REDIRECT_FIELD_NAME, login as auth_login, logout
 from django.contrib.auth.decorators import login_required
 from django.contrib.auth.forms import AuthenticationForm, PasswordResetForm, SetPasswordForm, PasswordChangeForm
 from django.contrib.auth.tokens import default_token_generator
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 
 
 @sensitive_post_parameters()

django/contrib/comments/feeds.py

@@ -1,5 +1,5 @@
 from django.contrib.syndication.views import Feed
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.contrib import comments
 from django.utils.translation import ugettext as _
 

django/contrib/comments/moderation.py

@@ -62,7 +62,7 @@ from django.contrib.comments import signals
 from django.db.models.base import ModelBase
 from django.template import Context, loader
 from django.contrib import comments
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.utils import timezone
 
 class AlreadyModerated(Exception):

django/contrib/contenttypes/tests.py

@@ -2,7 +2,7 @@ from __future__ import unicode_literals
 
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.contenttypes.views import shortcut
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.db import models
 from django.http import HttpRequest, Http404
 from django.test import TestCase, override_settings

django/contrib/contenttypes/views.py

@@ -2,7 +2,8 @@ from __future__ import unicode_literals
 
 from django import http
 from django.contrib.contenttypes.models import ContentType
-from django.contrib.sites.models import Site, get_current_site
+from django.contrib.sites.models import Site
+from django.contrib.sites.shortcuts import get_current_site
 from django.core.exceptions import ObjectDoesNotExist
 from django.utils.translation import ugettext as _
 

django/contrib/flatpages/templatetags/flatpages.py

@@ -1,7 +1,7 @@
 from django import template
 from django.conf import settings
 from django.contrib.flatpages.models import FlatPage
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 
 
 register = template.Library()

django/contrib/flatpages/views.py

@@ -1,6 +1,6 @@
 from django.conf import settings
 from django.contrib.flatpages.models import FlatPage
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.http import Http404, HttpResponse, HttpResponsePermanentRedirect
 from django.shortcuts import get_object_or_404
 from django.template import loader, RequestContext

django/contrib/gis/sitemaps/views.py

@@ -5,7 +5,7 @@ import warnings
 from django.apps import apps
 from django.http import HttpResponse, Http404
 from django.template import loader
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.core import urlresolvers
 from django.core.paginator import EmptyPage, PageNotAnInteger
 from django.contrib.gis.db.models.fields import GeometryField

django/contrib/redirects/middleware.py

@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 from django.apps import apps
 from django.conf import settings
 from django.contrib.redirects.models import Redirect
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.core.exceptions import ImproperlyConfigured
 from django import http
 

django/contrib/sitemaps/views.py

@@ -1,7 +1,7 @@
 from calendar import timegm
 from functools import wraps
 
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.core import urlresolvers
 from django.core.paginator import EmptyPage, PageNotAnInteger
 from django.http import Http404

django/contrib/sites/models.py

@@ -1,6 +1,7 @@
 from __future__ import unicode_literals
 
 import string
+import warnings
 
 from django.core.exceptions import ImproperlyConfigured, ValidationError
 from django.db import models
@@ -8,6 +9,9 @@ from django.db.models.signals import pre_save, pre_delete
 from django.utils.translation import ugettext_lazy as _
 from django.utils.encoding import python_2_unicode_compatible
 
+from .requests import RequestSite as RealRequestSite
+from .shortcuts import get_current_site as real_get_current_site
+
 
 SITE_CACHE = {}
 
@@ -74,38 +78,19 @@ class Site(models.Model):
         return self.domain
 
 
-@python_2_unicode_compatible
-class RequestSite(object):
-    """
-    A class that shares the primary interface of Site (i.e., it has
-    ``domain`` and ``name`` attributes) but gets its data from a Django
-    HttpRequest object rather than from a database.
-
-    The save() and delete() methods raise NotImplementedError.
-    """
-    def __init__(self, request):
-        self.domain = self.name = request.get_host()
-
-    def __str__(self):
-        return self.domain
-
-    def save(self, force_insert=False, force_update=False):
-        raise NotImplementedError('RequestSite cannot be saved.')
-
-    def delete(self):
-        raise NotImplementedError('RequestSite cannot be deleted.')
+class RequestSite(RealRequestSite):
+    def __init__(self, *args, **kwargs):
+        warnings.warn(
+            "Please import RequestSite from django.contrib.sites.requests.",
+            PendingDeprecationWarning, stacklevel=2)
+        super(RequestSite, self).__init__(*args, **kwargs)
 
 
 def get_current_site(request):
-    """
-    Checks if contrib.sites is installed and returns either the current
-    ``Site`` object or a ``RequestSite`` object based on the request.
-    """
-    if Site._meta.installed:
-        current_site = Site.objects.get_current()
-    else:
-        current_site = RequestSite(request)
-    return current_site
+    warnings.warn(
+        "Please import get_current_site from django.contrib.sites.shortcuts.",
+        PendingDeprecationWarning, stacklevel=2)
+    return real_get_current_site(request)
 
 
 def clear_site_cache(sender, **kwargs):

django/contrib/sites/requests.py

@@ -0,0 +1,25 @@
+from __future__ import unicode_literals
+
+from django.utils.encoding import python_2_unicode_compatible
+
+
+@python_2_unicode_compatible
+class RequestSite(object):
+    """
+    A class that shares the primary interface of Site (i.e., it has
+    ``domain`` and ``name`` attributes) but gets its data from a Django
+    HttpRequest object rather than from a database.
+
+    The save() and delete() methods raise NotImplementedError.
+    """
+    def __init__(self, request):
+        self.domain = self.name = request.get_host()
+
+    def __str__(self):
+        return self.domain
+
+    def save(self, force_insert=False, force_update=False):
+        raise NotImplementedError('RequestSite cannot be saved.')
+
+    def delete(self):
+        raise NotImplementedError('RequestSite cannot be deleted.')

django/contrib/sites/shortcuts.py

@@ -0,0 +1,18 @@
+from __future__ import unicode_literals
+
+from django.apps import apps
+
+
+def get_current_site(request):
+    """
+    Checks if contrib.sites is installed and returns either the current
+    ``Site`` object or a ``RequestSite`` object based on the request.
+    """
+    # Imports are inside the function because its point is to avoid importing
+    # the Site models when django.contrib.sites isn't installed.
+    if apps.is_installed('django.contrib.sites'):
+        from .models import Site
+        return Site.objects.get_current()
+    else:
+        from .requests import RequestSite
+        return RequestSite(request)

django/contrib/sites/tests.py

@@ -1,11 +1,14 @@
 from __future__ import unicode_literals
 
 from django.conf import settings
-from django.contrib.sites.models import Site, RequestSite, get_current_site
 from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.http import HttpRequest
 from django.test import TestCase, modify_settings, override_settings
 
+from .models import Site
+from .requests import RequestSite
+from .shortcuts import get_current_site
+
 
 @modify_settings(INSTALLED_APPS={'append': 'django.contrib.sites'})
 class SitesFrameworkTests(TestCase):

django/contrib/syndication/views.py

@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 from calendar import timegm
 
 from django.conf import settings
-from django.contrib.sites.models import get_current_site
+from django.contrib.sites.shortcuts import get_current_site
 from django.core.exceptions import ImproperlyConfigured, ObjectDoesNotExist
 from django.http import HttpResponse, Http404
 from django.template import loader, TemplateDoesNotExist, RequestContext

django/views/decorators/cache.py

@@ -12,7 +12,7 @@ def cache_page(*args, **kwargs):
     The cache is keyed by the URL and some data from the headers.
     Additionally there is the key prefix that is used to distinguish different
     cache areas in a multi-site setup. You could use the
-    sites.get_current_site().domain, for example, as that is unique across a Django
+    get_current_site().domain, for example, as that is unique across a Django
     project.
 
     Additionally, all headers from the response's Vary header will be taken