get_realm: raise DoesNotExist instead of returning None.

This makes the implementation of `get_realm` consistent with its
declared return type of `Realm` rather than `Optional[Realm]`.

Fixes #12263.

Signed-off-by: Anders Kaseorg <anders@zulipchat.com>

analytics/views.py

@@ -82,8 +82,9 @@ def stats(request: HttpRequest) -> HttpResponse:
 @require_server_admin
 @has_request_variables
 def stats_for_realm(request: HttpRequest, realm_str: str) -> HttpResponse:
-    realm = get_realm(realm_str)
+    try:
-    if realm is None:
+        realm = get_realm(realm_str)
+    except Realm.DoesNotExist:
         return HttpResponseNotFound("Realm %s does not exist" % (realm_str,))
 
     return render_stats(request, '/realm/%s' % (realm_str,), realm.name or realm.string_id)
@@ -100,8 +101,9 @@ def stats_for_remote_realm(request: HttpRequest, remote_server_id: str,
 @has_request_variables
 def get_chart_data_for_realm(request: HttpRequest, user_profile: UserProfile,
                              realm_str: str, **kwargs: Any) -> HttpResponse:
-    realm = get_realm(realm_str)
+    try:
-    if realm is None:
+        realm = get_realm(realm_str)
+    except Realm.DoesNotExist:
         raise JsonableError(_("Invalid organization"))
 
     return get_chart_data(request=request, user_profile=user_profile, realm=realm, **kwargs)
@@ -1088,9 +1090,10 @@ def support(request: HttpRequest) -> HttpResponse:
                 if parse_result.port:
                     hostname = "{}:{}".format(hostname, parse_result.port)
                 subdomain = get_subdomain_from_hostname(hostname)
-                realm = get_realm(subdomain)
+                try:
-                if realm is not None:
+                    realms.add(get_realm(subdomain))
-                    realms.add(realm)
+                except Realm.DoesNotExist:
+                    pass
             except ValidationError:
                 pass
 

zerver/context_processors.py

@@ -1,5 +1,4 @@
-
+from typing import Any, Dict, Optional
-from typing import Any, Dict
 from django.http import HttpRequest
 from django.conf import settings
 from django.urls import reverse
@@ -35,7 +34,7 @@ def common_context(user: UserProfile) -> Dict[str, Any]:
         'user_name': user.full_name,
     }
 
-def get_realm_from_request(request: HttpRequest) -> Realm:
+def get_realm_from_request(request: HttpRequest) -> Optional[Realm]:
     if hasattr(request, "user") and hasattr(request.user, "realm"):
         return request.user.realm
     if not hasattr(request, "realm"):
@@ -44,7 +43,10 @@ def get_realm_from_request(request: HttpRequest) -> Realm:
         # need to do duplicate queries on the same realm while
         # processing a single request.
         subdomain = get_subdomain(request)
-        request.realm = get_realm(subdomain)
+        try:
+            request.realm = get_realm(subdomain)
+        except Realm.DoesNotExist:
+            request.realm = None
     return request.realm
 
 def zulip_default_context(request: HttpRequest) -> Dict[str, Any]:

zerver/forms.py

@@ -79,7 +79,7 @@ def check_subdomain_available(subdomain: str, from_management_command: bool=Fals
     if len(subdomain) < 3:
         raise ValidationError(error_strings['too short'])
     if is_reserved_subdomain(subdomain) or \
-       get_realm(subdomain) is not None:
+       Realm.objects.filter(string_id=subdomain).exists():
         raise ValidationError(error_strings['unavailable'])
 
 class RegistrationForm(forms.Form):
@@ -279,7 +279,10 @@ class OurAuthenticationForm(AuthenticationForm):
 
         if username is not None and password:
             subdomain = get_subdomain(self.request)
-            realm = get_realm(subdomain)
+            try:
+                realm = get_realm(subdomain)  # type: Optional[Realm]
+            except Realm.DoesNotExist:
+                realm = None
             return_data = {}  # type: Dict[str, Any]
             self.user_cache = authenticate(self.request, username=username, password=password,
                                            realm=realm, return_data=return_data)
@@ -356,6 +359,8 @@ class RealmRedirectForm(forms.Form):
 
     def clean_subdomain(self) -> str:
         subdomain = self.cleaned_data['subdomain']
-        if get_realm(subdomain) is None:
+        try:
+            get_realm(subdomain)
+        except Realm.DoesNotExist:
             raise ValidationError(_("We couldn't find that Zulip organization."))
         return subdomain

zerver/lib/actions.py

@@ -93,7 +93,7 @@ from zerver.models import Realm, RealmEmoji, Stream, UserProfile, UserActivity,
     ScheduledEmail, MAX_TOPIC_NAME_LENGTH, \
     MAX_MESSAGE_LENGTH, get_client, get_stream, get_personal_recipient, \
     get_user_profile_by_id, PreregistrationUser, \
-    get_realm, bulk_get_recipients, get_stream_recipient, get_stream_recipients, \
+    bulk_get_recipients, get_stream_recipient, get_stream_recipients, \
     email_allowed_for_realm, email_to_username, display_recipient_cache_key, \
     get_user_by_delivery_email, get_stream_cache_key, active_non_guest_user_ids, \
     UserActivityInterval, active_user_ids, get_active_streams, \
@@ -3536,8 +3536,7 @@ def do_change_stream_description(stream: Stream, new_description: str) -> None:
 
 def do_create_realm(string_id: str, name: str,
                     emails_restricted_to_domains: Optional[bool]=None) -> Realm:
-    existing_realm = get_realm(string_id)
+    if Realm.objects.filter(string_id=string_id).exists():
-    if existing_realm is not None:
         raise AssertionError("Realm %s already exists!" % (string_id,))
 
     kwargs = {}  # type: Dict[str, Any]

zerver/lib/subdomains.py

@@ -5,7 +5,7 @@ from django.http import HttpRequest
 import re
 from typing import Optional
 
-from zerver.models import get_realm, Realm, UserProfile
+from zerver.models import Realm, UserProfile
 
 def get_subdomain(request: HttpRequest) -> str:
 
@@ -51,4 +51,4 @@ def user_matches_subdomain(realm_subdomain: Optional[str], user_profile: UserPro
 def is_root_domain_available() -> bool:
     if settings.ROOT_DOMAIN_LANDING_PAGE:
         return False
-    return get_realm(Realm.SUBDOMAIN_FOR_ROOT_DOMAIN) is None
+    return not Realm.objects.filter(string_id=Realm.SUBDOMAIN_FOR_ROOT_DOMAIN).exists()

zerver/middleware.py

@@ -369,8 +369,9 @@ class SessionHostDomainMiddleware(SessionMiddleware):
                 not request.path.startswith("/json/")):
             subdomain = get_subdomain(request)
             if subdomain != Realm.SUBDOMAIN_FOR_ROOT_DOMAIN:
-                realm = get_realm(subdomain)
+                try:
-                if (realm is None):
+                    get_realm(subdomain)
+                except Realm.DoesNotExist:
                     return render(request, "zerver/invalid_realm.html", status=404)
         """
         If request.session was modified, or if the configuration is to save the

zerver/models.py

@@ -489,7 +489,7 @@ class Realm(models.Model):
 post_save.connect(flush_realm, sender=Realm)
 
 def get_realm(string_id: str) -> Realm:
-    return Realm.objects.filter(string_id=string_id).first()
+    return Realm.objects.get(string_id=string_id)
 
 def name_changes_disabled(realm: Optional[Realm]) -> bool:
     if realm is None:
@@ -1949,7 +1949,7 @@ def get_system_bot(email: str) -> UserProfile:
 
 def get_user_by_id_in_realm_including_cross_realm(
         uid: int,
-        realm: Realm
+        realm: Optional[Realm]
 ) -> UserProfile:
     user_profile = get_user_profile_by_id(uid)
     if user_profile.realm == realm:
@@ -1986,14 +1986,9 @@ def active_non_guest_user_ids(realm_id: int) -> List[int]:
     return list(query)
 
 def get_source_profile(email: str, string_id: str) -> Optional[UserProfile]:
-    realm = get_realm(string_id)
-
-    if realm is None:
-        return None
-
     try:
-        return get_user_by_delivery_email(email, realm)
+        return get_user_by_delivery_email(email, get_realm(string_id))
-    except UserProfile.DoesNotExist:
+    except (Realm.DoesNotExist, UserProfile.DoesNotExist):
         return None
 
 @cache_with_key(bot_dicts_in_realm_cache_key, timeout=3600*24*7)

zerver/tests/test_auth_backends.py

@@ -245,7 +245,7 @@ class AuthBackendTest(ZulipTestCase):
         with mock.patch('apiclient.sample_tools.client.verify_id_token', return_value=payload):
             self.verify_backend(backend,
                                 good_kwargs=dict(realm=get_realm("zulip")),
-                                bad_kwargs=dict(realm=get_realm('invalid')))
+                                bad_kwargs=dict(realm=None))
 
         # Verify valid_attestation parameter is set correctly
         unverified_payload = dict(email_verified=False)
@@ -301,7 +301,7 @@ class AuthBackendTest(ZulipTestCase):
             self.verify_backend(backend,
                                 bad_kwargs=dict(username=username,
                                                 password=password,
-                                                realm=get_realm('acme')),
+                                                realm=None),
                                 good_kwargs=dict(username=username,
                                                  password=password,
                                                  realm=get_realm('zulip')))
@@ -311,7 +311,7 @@ class AuthBackendTest(ZulipTestCase):
                             good_kwargs=dict(dev_auth_username=self.get_username(),
                                              realm=get_realm("zulip")),
                             bad_kwargs=dict(dev_auth_username=self.get_username(),
-                                            realm=get_realm("invalid")))
+                                            realm=None))
 
     @override_settings(AUTHENTICATION_BACKENDS=('zproject.backends.ZulipRemoteUserBackend',))
     def test_remote_user_backend(self) -> None:

zerver/tests/test_custom_profile_data.py

@@ -2,13 +2,13 @@
 
 from typing import Union, List, Dict, Any
 
-from zerver.lib.actions import get_realm, try_add_realm_custom_profile_field, \
+from zerver.lib.actions import try_add_realm_custom_profile_field, \
     do_update_user_custom_profile_data, do_remove_realm_custom_profile_field, \
     try_reorder_realm_custom_profile_fields
 from zerver.lib.test_classes import ZulipTestCase
 from zerver.lib.bugdown import convert as bugdown_convert
 from zerver.models import CustomProfileField, \
-    custom_profile_fields_for_realm, CustomProfileFieldValue
+    custom_profile_fields_for_realm, CustomProfileFieldValue, get_realm
 import ujson
 
 class CustomProfileFieldTest(ZulipTestCase):

zerver/tests/test_management_commands.py

@@ -251,7 +251,8 @@ class TestGenerateRealmCreationLink(ZulipTestCase):
         self.assert_in_success_response([u"Create a new Zulip organization"], result)
 
         # Enter email
-        self.assertIsNone(get_realm('test'))
+        with self.assertRaises(Realm.DoesNotExist):
+            get_realm('test')
         result = self.client_post(generated_link, {'email': email})
         self.assertEqual(result.status_code, 302)
         self.assertTrue(re.search(r'/accounts/do_confirm/\w+$', result["Location"]))

zerver/tests/test_messages.py

@@ -3619,7 +3619,7 @@ class CheckMessageTest(ZulipTestCase):
         )
         content = 'whatever'
         good_realm = test_bot.realm
-        wrong_realm = get_realm('mit')
+        wrong_realm = get_realm("zephyr")
         wrong_sender = cordelia
 
         send_rate_limited_pm_notification_to_bot_owner(test_bot, wrong_realm, content)

zerver/tests/test_realm.py

@@ -174,7 +174,8 @@ class RealmTest(ZulipTestCase):
         user = get_user_profile_by_email('hamlet@zulip.com')
         self.assertEqual(user.realm.string_id, "newzulip")
         # This doesn't use a cache right now, but may later.
-        self.assertIsNone(get_realm("zulip"))
+        with self.assertRaises(Realm.DoesNotExist):
+            get_realm("zulip")
 
     def test_do_deactivate_realm_clears_scheduled_jobs(self) -> None:
         user = self.example_user('hamlet')

zerver/tests/test_realm_emoji.py

@@ -3,10 +3,10 @@
 import mock
 
 from zerver.lib.actions import do_create_realm, do_create_user, \
-    get_realm, check_add_realm_emoji
+    check_add_realm_emoji
 from zerver.lib.test_classes import ZulipTestCase
 from zerver.lib.test_helpers import get_test_image_file
-from zerver.models import Realm, RealmEmoji, UserProfile
+from zerver.models import Realm, RealmEmoji, UserProfile, get_realm
 
 class RealmEmojiTest(ZulipTestCase):
 

zerver/tests/test_realm_filters.py

@@ -2,9 +2,9 @@
 
 import re
 
-from zerver.lib.actions import get_realm, do_add_realm_filter
+from zerver.lib.actions import do_add_realm_filter
 from zerver.lib.test_classes import ZulipTestCase
-from zerver.models import RealmFilter
+from zerver.models import RealmFilter, get_realm
 
 class RealmFilterTest(ZulipTestCase):
 

zerver/tests/test_signup.py

@@ -455,7 +455,7 @@ class LoginTest(ZulipTestCase):
         with queries_captured() as queries:
             self.register(self.nonreg_email('test'), "test")
         # Ensure the number of queries we make is not O(streams)
-        self.assert_length(queries, 78)
+        self.assert_length(queries, 77)
         user_profile = self.nonreg_user('test')
         self.assertEqual(get_session_dict_user(self.client.session), user_profile.id)
         self.assertFalse(user_profile.enable_stream_desktop_notifications)
@@ -1674,9 +1674,9 @@ class RealmCreationTest(ZulipTestCase):
     def check_able_to_create_realm(self, email: str) -> None:
         password = "test"
         string_id = "zuliptest"
-        realm = get_realm(string_id)
         # Make sure the realm does not exist
-        self.assertIsNone(realm)
+        with self.assertRaises(Realm.DoesNotExist):
+            get_realm(string_id)
 
         # Create new realm with the email
         result = self.client_post('/new/', {'email': email})
@@ -1697,7 +1697,6 @@ class RealmCreationTest(ZulipTestCase):
 
         # Make sure the realm is created
         realm = get_realm(string_id)
-        self.assertIsNotNone(realm)
         self.assertEqual(realm.string_id, string_id)
         self.assertEqual(get_user(email, realm).realm, realm)
 
@@ -1748,7 +1747,8 @@ class RealmCreationTest(ZulipTestCase):
         realm_name = "Test"
 
         # Make sure the realm does not exist
-        self.assertIsNone(get_realm(string_id))
+        with self.assertRaises(Realm.DoesNotExist):
+            get_realm(string_id)
 
         # Create new realm with the email
         result = self.client_post('/new/', {'email': email})
@@ -1772,7 +1772,6 @@ class RealmCreationTest(ZulipTestCase):
 
         # Make sure the realm is created
         realm = get_realm(string_id)
-        self.assertIsNotNone(realm)
         self.assertEqual(realm.string_id, string_id)
         self.assertEqual(get_user(email, realm).realm, realm)
 

zerver/tests/test_subs.py

@@ -44,14 +44,14 @@ from zerver.models import (
     Realm, Recipient, Stream, Subscription,
     DefaultStream, UserProfile, get_user_profile_by_id, active_non_guest_user_ids,
     get_default_stream_groups, flush_per_request_caches, DefaultStreamGroup,
-    get_client, get_user
+    get_client, get_realm, get_user
 )
 
 from zerver.lib.actions import (
     do_add_default_stream, do_change_is_admin, do_set_realm_property,
     do_create_realm, do_remove_default_stream, bulk_get_subscriber_user_ids,
     gather_subscriptions_helper, bulk_add_subscriptions, bulk_remove_subscriptions,
-    gather_subscriptions, get_default_streams_for_realm, get_realm, get_stream,
+    gather_subscriptions, get_default_streams_for_realm, get_stream,
     do_get_streams, do_change_is_guest,
     create_stream_if_needed, create_streams_if_needed,
     ensure_stream,

zerver/tests/test_users.py

@@ -779,7 +779,7 @@ class UserProfileTest(ZulipTestCase):
         # Pass in the ID of a cross-realm bot but with a invalid realm,
         # note that the realm should be irrelevant here
         cross_realm_bot = get_user_by_id_in_realm_including_cross_realm(
-            bot.id, get_realm('invalid'))
+            bot.id, None)
         self.assertEqual(cross_realm_bot.email, bot.email)
         self.assertEqual(cross_realm_bot.id, bot.id)
 
@@ -793,7 +793,7 @@ class UserProfileTest(ZulipTestCase):
         # cross-realm bot, UserProfile.DoesNotExist is raised
         with self.assertRaises(UserProfile.DoesNotExist):
             get_user_by_id_in_realm_including_cross_realm(
-                hamlet.id, get_realm('invalid'))
+                hamlet.id, None)
 
 class ActivateTest(ZulipTestCase):
     def test_basics(self) -> None:

zerver/views/auth.py

@@ -64,7 +64,10 @@ def create_preregistration_user(email: str, request: HttpRequest, realm_creation
                                 password_required: bool=True) -> HttpResponse:
     realm = None
     if not realm_creation:
-        realm = get_realm(get_subdomain(request))
+        try:
+            realm = get_realm(get_subdomain(request))
+        except Realm.DoesNotExist:
+            pass
     return PreregistrationUser.objects.create(email=email,
                                               realm_creation=realm_creation,
                                               password_required=password_required,
@@ -80,17 +83,21 @@ def maybe_send_to_registration(request: HttpRequest, email: str, full_name: str=
     depending on is_signup, whether the email address can join the
     organization (checked in HomepageForm), and similar details.
     """
-    realm = get_realm(get_subdomain(request))
-    from_multiuse_invite = False
-    multiuse_obj = None
-    streams_to_subscribe = None
-    invited_as = PreregistrationUser.INVITE_AS['MEMBER']
     if multiuse_object_key:
         from_multiuse_invite = True
         multiuse_obj = Confirmation.objects.get(confirmation_key=multiuse_object_key).content_object
         realm = multiuse_obj.realm
         streams_to_subscribe = multiuse_obj.streams.all()
         invited_as = multiuse_obj.invited_as
+    else:
+        from_multiuse_invite = False
+        multiuse_obj = None
+        try:
+            realm = get_realm(get_subdomain(request))
+        except Realm.DoesNotExist:
+            realm = None
+        streams_to_subscribe = None
+        invited_as = PreregistrationUser.INVITE_AS['MEMBER']
 
     form = HomepageForm({'email': email}, realm=realm, from_multiuse_invite=from_multiuse_invite)
     if form.is_valid():
@@ -241,9 +248,12 @@ def remote_user_sso(request: HttpRequest,
             raise JsonableError(_("Invalid OTP"))
 
     subdomain = get_subdomain(request)
-    realm = get_realm(subdomain)
+    try:
+        realm = get_realm(subdomain)  # type: Optional[Realm]
+    except Realm.DoesNotExist:
+        realm = None
     # Since RemoteUserBackend will return None if Realm is None, we
-    # don't need to check whether `get_realm` returned None.
+    # don't need to check whether `realm` is None.
     return_data = {}  # type: Dict[str, Any]
     user_profile = authenticate(remote_user=remote_user, realm=realm,
                                 return_data=return_data)
@@ -282,8 +292,9 @@ def remote_user_jwt(request: HttpRequest) -> HttpResponse:
 
     email = "%s@%s" % (remote_user, email_domain)
 
-    realm = get_realm(subdomain)
+    try:
-    if realm is None:
+        realm = get_realm(subdomain)
+    except Realm.DoesNotExist:
         raise JsonableError(_("Wrong subdomain"))
 
     try:
@@ -604,7 +615,7 @@ def show_deactivation_notice(request: HttpRequest) -> HttpResponse:
 def redirect_to_deactivation_notice() -> HttpResponse:
     return HttpResponseRedirect(reverse('zerver.views.auth.show_deactivation_notice'))
 
-def add_dev_login_context(realm: Realm, context: Dict[str, Any]) -> None:
+def add_dev_login_context(realm: Optional[Realm], context: Dict[str, Any]) -> None:
     users = get_dev_users(realm)
     context['current_realm'] = realm
     context['all_realms'] = Realm.objects.all()
@@ -960,9 +971,7 @@ def logout_then_login(request: HttpRequest, **kwargs: Any) -> HttpResponse:
     return django_logout_then_login(request, kwargs)
 
 def password_reset(request: HttpRequest, **kwargs: Any) -> HttpResponse:
-    realm = get_realm(get_subdomain(request))
+    if not Realm.objects.filter(string_id=get_subdomain(request)).exists():
-
-    if realm is None:
         # If trying to get to password reset on a subdomain that
         # doesn't exist, just go to find_account.
         redirect_url = reverse('zerver.views.registration.find_account')

zerver/views/messages.py

@@ -1232,8 +1232,9 @@ def send_message_backend(request: HttpRequest, user_profile: UserProfile,
             # The email gateway bot needs to be able to send messages in
             # any realm.
             return json_error(_("User not authorized for this query"))
-        realm = get_realm(realm_str)
+        try:
-        if not realm:
+            realm = get_realm(realm_str)
+        except Realm.DoesNotExist:
             return json_error(_("Unknown organization '%s'") % (realm_str,))
 
     if client.name in ["zephyr_mirror", "irc_mirror", "jabber_mirror", "JabberMirror"]:

zerver/views/registration.py

@@ -85,10 +85,10 @@ def accounts_register(request: HttpRequest) -> HttpResponse:
         # For creating a new realm, there is no existing realm or domain
         realm = None
     else:
-        realm = get_realm(get_subdomain(request))
+        if get_subdomain(request) != prereg_user.realm.string_id:
-        if realm is None or realm != prereg_user.realm:
             return render_confirmation_key_error(
                 request, ConfirmationKeyException(ConfirmationKeyException.DOES_NOT_EXIST))
+        realm = prereg_user.realm
 
         try:
             email_allowed_for_realm(email, realm)
@@ -417,9 +417,9 @@ def create_realm(request: HttpRequest, creation_key: Optional[str]=None) -> Http
 
 def accounts_home(request: HttpRequest, multiuse_object_key: Optional[str]="",
                   multiuse_object: Optional[MultiuseInvite]=None) -> HttpResponse:
-    realm = get_realm(get_subdomain(request))
+    try:
-
+        realm = get_realm(get_subdomain(request))
-    if realm is None:
+    except Realm.DoesNotExist:
         return HttpResponseRedirect(reverse('zerver.views.registration.find_account'))
     if realm.deactivated:
         return redirect_to_deactivation_notice()

zproject/backends.py

@@ -653,8 +653,9 @@ def social_associate_user_helper(backend: BaseAuth, return_data: Dict[str, Any],
     Returns a UserProfile object for successful authentication, and None otherwise.
     """
     subdomain = backend.strategy.session_get('subdomain')
-    realm = get_realm(subdomain)
+    try:
-    if realm is None:
+        realm = get_realm(subdomain)
+    except Realm.DoesNotExist:
         return_data["invalid_realm"] = True
         return None
     return_data["realm_id"] = realm.id