Implement MSC4069: Inhibit profile propagation (#16636)

MSC: https://github.com/matrix-org/matrix-spec-proposals/pull/4069

6 files changed, 203 insertions, 5 deletions

diff --git a/changelog.d/16636.feature b/changelog.d/16636.feature
new file mode 100644
index 0000000000..a363eaafaf
--- /dev/null
+++ b/changelog.d/16636.feature
@@ -0,0 +1 @@
+Support MSC4069: Inhibit profile propagation.
\ No newline at end of file
diff --git a/synapse/config/experimental.py b/synapse/config/experimental.py
index 9f830e7094..6b9febe5a7 100644
--- a/synapse/config/experimental.py
+++ b/synapse/config/experimental.py
@@ -419,3 +419,7 @@ class ExperimentalConfig(Config):
         self.msc4028_push_encrypted_events = experimental.get(
             "msc4028_push_encrypted_events", False
         )
+
+        self.msc4069_profile_inhibit_propagation = experimental.get(
+            "msc4069_profile_inhibit_propagation", False
+        )
diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py
index 1027fbfd28..e043fd5322 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -129,6 +129,7 @@ class ProfileHandler:
         new_displayname: str,
         by_admin: bool = False,
         deactivation: bool = False,
+        propagate: bool = True,
     ) -> None:
         """Set the displayname of a user
 
@@ -138,6 +139,7 @@ class ProfileHandler:
             new_displayname: The displayname to give this user.
             by_admin: Whether this change was made by an administrator.
             deactivation: Whether this change was made while deactivating the user.
+            propagate: Whether this change also applies to the user's membership events.
         """
         if not self.hs.is_mine(target_user):
             raise SynapseError(400, "User is not hosted on this homeserver")
@@ -188,7 +190,8 @@ class ProfileHandler:
             target_user.to_string(), profile, by_admin, deactivation
         )
 
-        await self._update_join_states(requester, target_user)
+        if propagate:
+            await self._update_join_states(requester, target_user)
 
     async def get_avatar_url(self, target_user: UserID) -> Optional[str]:
         if self.hs.is_mine(target_user):
@@ -221,6 +224,7 @@ class ProfileHandler:
         new_avatar_url: str,
         by_admin: bool = False,
         deactivation: bool = False,
+        propagate: bool = True,
     ) -> None:
         """Set a new avatar URL for a user.
 
@@ -230,6 +234,7 @@ class ProfileHandler:
             new_avatar_url: The avatar URL to give this user.
             by_admin: Whether this change was made by an administrator.
             deactivation: Whether this change was made while deactivating the user.
+            propagate: Whether this change also applies to the user's membership events.
         """
         if not self.hs.is_mine(target_user):
             raise SynapseError(400, "User is not hosted on this homeserver")
@@ -278,7 +283,8 @@ class ProfileHandler:
             target_user.to_string(), profile, by_admin, deactivation
         )
 
-        await self._update_join_states(requester, target_user)
+        if propagate:
+            await self._update_join_states(requester, target_user)
 
     @cached()
     async def check_avatar_size_and_mime_type(self, mxc: str) -> bool:
diff --git a/synapse/rest/client/profile.py b/synapse/rest/client/profile.py
index 493e1acea0..12d3da1ced 100644
--- a/synapse/rest/client/profile.py
+++ b/synapse/rest/client/profile.py
@@ -13,12 +13,17 @@
 # limitations under the License.
 
 """ This module contains REST servlets to do with profile: /profile/<paths> """
+
 from http import HTTPStatus
 from typing import TYPE_CHECKING, Tuple
 
 from synapse.api.errors import Codes, SynapseError
 from synapse.http.server import HttpServer
-from synapse.http.servlet import RestServlet, parse_json_object_from_request
+from synapse.http.servlet import (
+    RestServlet,
+    parse_boolean,
+    parse_json_object_from_request,
+)
 from synapse.http.site import SynapseRequest
 from synapse.rest.client._base import client_patterns
 from synapse.types import JsonDict, UserID
@@ -27,6 +32,20 @@ if TYPE_CHECKING:
     from synapse.server import HomeServer
 
 
+def _read_propagate(hs: "HomeServer", request: SynapseRequest) -> bool:
+    # This will always be set by the time Twisted calls us.
+    assert request.args is not None
+
+    propagate = True
+    if hs.config.experimental.msc4069_profile_inhibit_propagation:
+        do_propagate = request.args.get(b"org.matrix.msc4069.propagate")
+        if do_propagate is not None:
+            propagate = parse_boolean(
+                request, "org.matrix.msc4069.propagate", default=False
+            )
+    return propagate
+
+
 class ProfileDisplaynameRestServlet(RestServlet):
     PATTERNS = client_patterns("/profile/(?P<user_id>[^/]*)/displayname", v1=True)
     CATEGORY = "Event sending requests"
@@ -80,7 +99,11 @@ class ProfileDisplaynameRestServlet(RestServlet):
                 errcode=Codes.BAD_JSON,
             )
 
-        await self.profile_handler.set_displayname(user, requester, new_name, is_admin)
+        propagate = _read_propagate(self.hs, request)
+
+        await self.profile_handler.set_displayname(
+            user, requester, new_name, is_admin, propagate=propagate
+        )
 
         return 200, {}
 
@@ -135,8 +158,10 @@ class ProfileAvatarURLRestServlet(RestServlet):
                 400, "Missing key 'avatar_url'", errcode=Codes.MISSING_PARAM
             )
 
+        propagate = _read_propagate(self.hs, request)
+
         await self.profile_handler.set_avatar_url(
-            user, requester, new_avatar_url, is_admin
+            user, requester, new_avatar_url, is_admin, propagate=propagate
         )
 
         return 200, {}
diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index f4d19e0470..54c01bb739 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -129,6 +129,8 @@ class VersionsRestServlet(RestServlet):
                     "org.matrix.msc3981": self.config.experimental.msc3981_recurse_relations,
                     # Adds support for deleting account data.
                     "org.matrix.msc3391": self.config.experimental.msc3391_enabled,
+                    # Allows clients to inhibit profile update propagation.
+                    "org.matrix.msc4069": self.config.experimental.msc4069_profile_inhibit_propagation,
                 },
             },
         )
diff --git a/tests/rest/client/test_profile.py b/tests/rest/client/test_profile.py
index 8f923fd40f..eb0fa00bb3 100644
--- a/tests/rest/client/test_profile.py
+++ b/tests/rest/client/test_profile.py
@@ -312,6 +312,166 @@ class ProfileTestCase(unittest.HomeserverTestCase):
         )
         self.assertEqual(channel.code, 200, channel.result)
 
+    @unittest.override_config(
+        {"experimental_features": {"msc4069_profile_inhibit_propagation": True}}
+    )
+    def test_msc4069_inhibit_propagation(self) -> None:
+        """Tests to ensure profile update propagation can be inhibited."""
+        for prop in ["avatar_url", "displayname"]:
+            room_id = self.helper.create_room_as(tok=self.owner_tok)
+
+            channel = self.make_request(
+                "PUT",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                content={"membership": "join", prop: "mxc://my.server/existing"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            channel = self.make_request(
+                "PUT",
+                f"/profile/{self.owner}/{prop}?org.matrix.msc4069.propagate=false",
+                content={prop: "http://my.server/pic.gif"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            res = (
+                self._get_avatar_url()
+                if prop == "avatar_url"
+                else self._get_displayname()
+            )
+            self.assertEqual(res, "http://my.server/pic.gif")
+
+            channel = self.make_request(
+                "GET",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+            self.assertEqual(channel.json_body.get(prop), "mxc://my.server/existing")
+
+    def test_msc4069_inhibit_propagation_disabled(self) -> None:
+        """Tests to ensure profile update propagation inhibit flags are ignored when the
+        experimental flag is not enabled.
+        """
+        for prop in ["avatar_url", "displayname"]:
+            room_id = self.helper.create_room_as(tok=self.owner_tok)
+
+            channel = self.make_request(
+                "PUT",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                content={"membership": "join", prop: "mxc://my.server/existing"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            channel = self.make_request(
+                "PUT",
+                f"/profile/{self.owner}/{prop}?org.matrix.msc4069.propagate=false",
+                content={prop: "http://my.server/pic.gif"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            res = (
+                self._get_avatar_url()
+                if prop == "avatar_url"
+                else self._get_displayname()
+            )
+            self.assertEqual(res, "http://my.server/pic.gif")
+
+            channel = self.make_request(
+                "GET",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            # The ?propagate=false should be ignored by the server because the config flag
+            # isn't enabled.
+            self.assertEqual(channel.json_body.get(prop), "http://my.server/pic.gif")
+
+    def test_msc4069_inhibit_propagation_default(self) -> None:
+        """Tests to ensure profile update propagation happens by default."""
+        for prop in ["avatar_url", "displayname"]:
+            room_id = self.helper.create_room_as(tok=self.owner_tok)
+
+            channel = self.make_request(
+                "PUT",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                content={"membership": "join", prop: "mxc://my.server/existing"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            channel = self.make_request(
+                "PUT",
+                f"/profile/{self.owner}/{prop}",
+                content={prop: "http://my.server/pic.gif"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            res = (
+                self._get_avatar_url()
+                if prop == "avatar_url"
+                else self._get_displayname()
+            )
+            self.assertEqual(res, "http://my.server/pic.gif")
+
+            channel = self.make_request(
+                "GET",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            # The ?propagate=false should be ignored by the server because the config flag
+            # isn't enabled.
+            self.assertEqual(channel.json_body.get(prop), "http://my.server/pic.gif")
+
+    @unittest.override_config(
+        {"experimental_features": {"msc4069_profile_inhibit_propagation": True}}
+    )
+    def test_msc4069_inhibit_propagation_like_default(self) -> None:
+        """Tests to ensure clients can request explicit profile propagation."""
+        for prop in ["avatar_url", "displayname"]:
+            room_id = self.helper.create_room_as(tok=self.owner_tok)
+
+            channel = self.make_request(
+                "PUT",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                content={"membership": "join", prop: "mxc://my.server/existing"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            channel = self.make_request(
+                "PUT",
+                f"/profile/{self.owner}/{prop}?org.matrix.msc4069.propagate=true",
+                content={prop: "http://my.server/pic.gif"},
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            res = (
+                self._get_avatar_url()
+                if prop == "avatar_url"
+                else self._get_displayname()
+            )
+            self.assertEqual(res, "http://my.server/pic.gif")
+
+            channel = self.make_request(
+                "GET",
+                f"/rooms/{room_id}/state/m.room.member/{self.owner}",
+                access_token=self.owner_tok,
+            )
+            self.assertEqual(channel.code, 200, channel.result)
+
+            # The client requested ?propagate=true, so it should have happened.
+            self.assertEqual(channel.json_body.get(prop), "http://my.server/pic.gif")
+
     def _setup_local_files(self, names_and_props: Dict[str, Dict[str, Any]]) -> None:
         """Stores metadata about files in the database.