Remove support for the unstable dir flag on relations. (#14106)

From MSC3715, this was unused by clients (and there was no
way for clients to know it was supported).

Matrix 1.4 defines the stable field.

1 files changed, 10 insertions, 35 deletions

diff --git a/synapse/rest/client/relations.py b/synapse/rest/client/relations.py
index 7a25de5c85..b31ce5a0d3 100644
--- a/synapse/rest/client/relations.py
+++ b/synapse/rest/client/relations.py
@@ -16,10 +16,11 @@ import logging
 from typing import TYPE_CHECKING, Optional, Tuple
 
 from synapse.http.server import HttpServer
-from synapse.http.servlet import RestServlet, parse_integer, parse_string
+from synapse.http.servlet import RestServlet
 from synapse.http.site import SynapseRequest
 from synapse.rest.client._base import client_patterns
-from synapse.types import JsonDict, StreamToken
+from synapse.streams.config import PaginationConfig
+from synapse.types import JsonDict
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
@@ -41,9 +42,8 @@ class RelationPaginationServlet(RestServlet):
     def __init__(self, hs: "HomeServer"):
         super().__init__()
         self.auth = hs.get_auth()
-        self.store = hs.get_datastores().main
+        self._store = hs.get_datastores().main
         self._relations_handler = hs.get_relations_handler()
-        self._msc3715_enabled = hs.config.experimental.msc3715_enabled
 
     async def on_GET(
         self,
@@ -55,49 +55,24 @@ class RelationPaginationServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request, allow_guest=True)
 
-        limit = parse_integer(request, "limit", default=5)
-        # Fetch the direction parameter, if provided.
-        #
-        # TODO Use PaginationConfig.from_request when the unstable parameter is
-        #      no longer needed.
-        direction = parse_string(request, "dir", allowed_values=["f", "b"])
-        if direction is None:
-            if self._msc3715_enabled:
-                direction = parse_string(
-                    request,
-                    "org.matrix.msc3715.dir",
-                    default="b",
-                    allowed_values=["f", "b"],
-                )
-            else:
-                direction = "b"
-        from_token_str = parse_string(request, "from")
-        to_token_str = parse_string(request, "to")
-
-        # Return the relations
-        from_token = None
-        if from_token_str:
-            from_token = await StreamToken.from_string(self.store, from_token_str)
-        to_token = None
-        if to_token_str:
-            to_token = await StreamToken.from_string(self.store, to_token_str)
+        pagination_config = await PaginationConfig.from_request(
+            self._store, request, default_limit=5, default_dir="b"
+        )
 
         # The unstable version of this API returns an extra field for client
         # compatibility, see https://github.com/matrix-org/synapse/issues/12930.
         assert request.path is not None
         include_original_event = request.path.startswith(b"/_matrix/client/unstable/")
 
+        # Return the relations
         result = await self._relations_handler.get_relations(
             requester=requester,
             event_id=parent_id,
             room_id=room_id,
+            pagin_config=pagination_config,
+            include_original_event=include_original_event,
             relation_type=relation_type,
             event_type=event_type,
-            limit=limit,
-            direction=direction,
-            from_token=from_token,
-            to_token=to_token,
-            include_original_event=include_original_event,
         )
 
         return 200, result