realm: Disable enable_spectator_access on changing to limited plan.

Since we not allow enabling public access on limited plan realms,
we set the enable_spectator_access setting to False when downgrading
to a limited plan. Setting is still shown in the UI but it is
disabled.

zerver/actions/create_realm.py

@@ -166,6 +166,10 @@ def do_create_realm(
     if org_type is not None:
         kwargs["org_type"] = org_type
     if enable_spectator_access is not None:
+        if enable_spectator_access:
+            # Realms with LIMITED plan cannot have spectators enabled.
+            assert plan_type != Realm.PLAN_TYPE_LIMITED
+            assert plan_type is not None or not settings.BILLING_ENABLED
         kwargs["enable_spectator_access"] = enable_spectator_access
 
     if date_created is not None:

zerver/actions/realm_settings.py

@@ -416,6 +416,11 @@ def do_change_realm_plan_type(
     realm: Realm, plan_type: int, *, acting_user: Optional[UserProfile]
 ) -> None:
     old_value = realm.plan_type
+
+    if plan_type == Realm.PLAN_TYPE_LIMITED:
+        # We do not allow public access on limited plans.
+        do_set_realm_property(realm, "enable_spectator_access", False, acting_user=acting_user)
+
     realm.plan_type = plan_type
     realm.save(update_fields=["plan_type"])
     RealmAuditLog.objects.create(
@@ -451,7 +456,14 @@ def do_change_realm_plan_type(
 
     update_first_visible_message_id(realm)
 
-    realm.save(update_fields=["_max_invites", "message_visibility_limit", "upload_quota_gb"])
+    realm.save(
+        update_fields=[
+            "_max_invites",
+            "enable_spectator_access",
+            "message_visibility_limit",
+            "upload_quota_gb",
+        ]
+    )
 
     event = {
         "type": "realm",

zerver/tests/test_events.py

@@ -1766,9 +1766,11 @@ class NormalActionsTest(BaseAction):
         events = self.verify_action(
             lambda: do_change_realm_plan_type(
                 realm, Realm.PLAN_TYPE_LIMITED, acting_user=self.user_profile
+            ),
+            num_events=2,
         )
-        )
+        check_realm_update("events[0]", events[0], "enable_spectator_access")
-        check_realm_update("events[0]", events[0], "plan_type")
+        check_realm_update("events[1]", events[1], "plan_type")
 
         state_data = fetch_initial_state_data(self.user_profile)
         self.assertEqual(state_data["realm_plan_type"], Realm.PLAN_TYPE_LIMITED)

zerver/tests/test_message_edit.py

@@ -427,6 +427,12 @@ class EditMessageTest(EditMessageTestCase):
             result, "Not logged in: API authentication or user session required", 401
         )
 
+        do_set_realm_property(user_profile.realm, "enable_spectator_access", True, acting_user=None)
+        result = self.client_get("/json/messages/" + str(web_public_stream_msg_id))
+        self.assert_json_error(
+            result, "Not logged in: API authentication or user session required", 401
+        )
+
         # Verify works with STANDARD_FREE plan type too.
         do_change_realm_plan_type(
             user_profile.realm, Realm.PLAN_TYPE_STANDARD_FREE, acting_user=None

zerver/tests/test_realm.py

@@ -97,12 +97,28 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.invite_to_stream_policy, Realm.POLICY_MODERATORS_ONLY)
 
     def test_realm_enable_spectator_access(self) -> None:
-        realm = do_create_realm("test_web_public_true", "Foo", enable_spectator_access=True)
+        realm = do_create_realm(
+            "test_web_public_true",
+            "Foo",
+            plan_type=Realm.PLAN_TYPE_STANDARD,
+            enable_spectator_access=True,
+        )
         self.assertEqual(realm.enable_spectator_access, True)
 
         realm = do_create_realm("test_web_public_false", "Boo", enable_spectator_access=False)
         self.assertEqual(realm.enable_spectator_access, False)
 
+        with self.assertRaises(AssertionError):
+            realm = do_create_realm("test_web_public_false_1", "Foo", enable_spectator_access=True)
+
+        with self.assertRaises(AssertionError):
+            realm = do_create_realm(
+                "test_web_public_false_2",
+                "Foo",
+                plan_type=Realm.PLAN_TYPE_LIMITED,
+                enable_spectator_access=True,
+            )
+
     def test_do_set_realm_name_caching(self) -> None:
         """The main complicated thing about setting realm names is fighting the
         cache, and we start by populating the cache for Hamlet, and we end
@@ -733,12 +749,14 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.message_visibility_limit, None)
         self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD)
 
+        do_set_realm_property(realm, "enable_spectator_access", True, acting_user=None)
         do_change_realm_plan_type(realm, Realm.PLAN_TYPE_LIMITED, acting_user=iago)
         realm = get_realm("zulip")
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_LIMITED)
         self.assertEqual(realm.max_invites, settings.INVITES_DEFAULT_REALM_DAILY_MAX)
         self.assertEqual(realm.message_visibility_limit, Realm.MESSAGE_VISIBILITY_LIMITED)
         self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_LIMITED)
+        self.assertFalse(realm.enable_spectator_access)
 
         do_change_realm_plan_type(realm, Realm.PLAN_TYPE_STANDARD_FREE, acting_user=iago)
         realm = get_realm("zulip")