Add a bulk user info endpoint and deprecate the old one

synapse/federation/federation_server.py

@@ -698,6 +698,19 @@ async def check_server_matches_acl(self, server_name: str, room_id: str):
 
         raise AuthError(code=403, msg="Server is banned from room")
 
+    async def on_user_info(self, user_ids: List[str]):
+        """Return user information given a list of user ids
+
+        Args:
+            user_ids: A list of users to return information about
+
+        Returns:
+            A dictionary mapping each user ID to a dict with the following keys:
+                * expired (bool) - whether this is an expired user
+                * deactivated (bool) - whether this is a deactivated user
+        """
+        return await self.store.get_info_for_users(user_ids)
+
 
 def server_matches_acl_event(server_name: str, acl_event: EventBase) -> bool:
     """Check if the given server is allowed by the ACL event

synapse/federation/transport/client.py

@@ -15,7 +15,7 @@
 # limitations under the License.
 
 import logging
-from typing import Any, Dict, Optional
+from typing import Any, Dict, List, Optional
 
 from six.moves import urllib
 
@@ -1021,6 +1021,20 @@ def get_room_complexity(self, destination, room_id):
 
         return self.client.get_json(destination=destination, path=path)
 
+    def get_info_of_users(self, destination: str, user_ids: List[str]):
+        """
+        Args:
+            destination: The remote server
+            user_ids: A list of user IDs to query info about
+
+        Returns:
+            Deferred[List]: A dictionary of User ID to information about that user.
+        """
+        path = _create_path(FEDERATION_UNSTABLE_PREFIX, "/user/info")
+        data = {"user_ids": user_ids}
+
+        return self.client.post_json(destination=destination, path=path, data=data)
+
 
 def _create_path(federation_prefix, path, *args):
     """

synapse/federation/transport/server.py

@@ -33,6 +33,7 @@
 from synapse.http.endpoint import parse_and_validate_server_name
 from synapse.http.server import JsonResource
 from synapse.http.servlet import (
+    assert_params_in_dict,
     parse_boolean_from_args,
     parse_integer_from_args,
     parse_json_object_from_request,
@@ -849,6 +850,57 @@ async def on_POST(self, origin, content, query):
         return 200, data
 
 
+class FederationUserInfoServlet(BaseFederationServlet):
+    """
+    Return information about a set of users.
+
+    This API returns expiration and deactivation information about a set of
+    users. Requested users not local to this homeserver will be ignored.
+
+    Example request:
+        POST /userinfo
+
+        {
+            "user_ids": [
+                "@alice:example.com",
+                "@bob:example.com"
+            ]
+        }
+
+    Example response
+        {
+            "@alice:example.com": {
+                "expired": false,
+                "deactivated": true
+            }
+        }
+    """
+
+    PATH = "/user/info"
+    PREFIX = FEDERATION_UNSTABLE_PREFIX
+
+    def __init__(self, handler, authenticator, ratelimiter, server_name):
+        super(FederationUserInfoServlet, self).__init__(
+            handler, authenticator, ratelimiter, server_name
+        )
+        self.handler = handler
+
+    async def on_POST(self, origin, content, query):
+        assert_params_in_dict(content, required=["user_ids"])
+
+        user_ids = content.get("user_ids", [])
+
+        if not isinstance(user_ids, list):
+            raise SynapseError(
+                400,
+                "'user_ids' must be a list of user ID strings",
+                errcode=Codes.INVALID_PARAM,
+            )
+
+        data = await self.handler.on_user_info(user_ids)
+        return 200, data
+
+
 class FederationVersionServlet(BaseFederationServlet):
     PATH = "/version"
 
@@ -1410,6 +1462,7 @@ async def on_GET(self, origin, content, query, room_id):
     On3pidBindServlet,
     FederationVersionServlet,
     RoomComplexityServlet,
+    FederationUserInfoServlet,
 )  # type: Tuple[Type[BaseFederationServlet], ...]
 
 OPENID_SERVLET_CLASSES = (