Support MSC3916 by adding `_matrix/client/v1/media/download` endpoint (#17365)

5 files changed, 76 insertions, 13 deletions

diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index f0f5a37a57..7d80ff6998 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -1871,6 +1871,52 @@ class FederationClient(FederationBase):
 
         return filtered_statuses, filtered_failures
 
+    async def federation_download_media(
+        self,
+        destination: str,
+        media_id: str,
+        output_stream: BinaryIO,
+        max_size: int,
+        max_timeout_ms: int,
+        download_ratelimiter: Ratelimiter,
+        ip_address: str,
+    ) -> Union[
+        Tuple[int, Dict[bytes, List[bytes]], bytes],
+        Tuple[int, Dict[bytes, List[bytes]]],
+    ]:
+        try:
+            return await self.transport_layer.federation_download_media(
+                destination,
+                media_id,
+                output_stream=output_stream,
+                max_size=max_size,
+                max_timeout_ms=max_timeout_ms,
+                download_ratelimiter=download_ratelimiter,
+                ip_address=ip_address,
+            )
+        except HttpResponseException as e:
+            # If an error is received that is due to an unrecognised endpoint,
+            # fallback to the _matrix/media/v3/download endpoint. Otherwise, consider it a legitimate error
+            # and raise.
+            if not is_unknown_endpoint(e):
+                raise
+
+        logger.debug(
+            "Couldn't download media %s/%s over _matrix/federation/v1/media/download, falling back to _matrix/media/v3/download path",
+            destination,
+            media_id,
+        )
+
+        return await self.transport_layer.download_media_v3(
+            destination,
+            media_id,
+            output_stream=output_stream,
+            max_size=max_size,
+            max_timeout_ms=max_timeout_ms,
+            download_ratelimiter=download_ratelimiter,
+            ip_address=ip_address,
+        )
+
     async def download_media(
         self,
         destination: str,
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index af1336fe5f..206e91ed14 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -824,7 +824,6 @@ class TransportLayerClient:
         ip_address: str,
     ) -> Tuple[int, Dict[bytes, List[bytes]]]:
         path = f"/_matrix/media/r0/download/{destination}/{media_id}"
-
         return await self.client.get_file(
             destination,
             path,
@@ -852,7 +851,6 @@ class TransportLayerClient:
         ip_address: str,
     ) -> Tuple[int, Dict[bytes, List[bytes]]]:
         path = f"/_matrix/media/v3/download/{destination}/{media_id}"
-
         return await self.client.get_file(
             destination,
             path,
@@ -873,6 +871,29 @@ class TransportLayerClient:
             ip_address=ip_address,
         )
 
+    async def federation_download_media(
+        self,
+        destination: str,
+        media_id: str,
+        output_stream: BinaryIO,
+        max_size: int,
+        max_timeout_ms: int,
+        download_ratelimiter: Ratelimiter,
+        ip_address: str,
+    ) -> Tuple[int, Dict[bytes, List[bytes]], bytes]:
+        path = f"/_matrix/federation/v1/media/download/{media_id}"
+        return await self.client.federation_get_file(
+            destination,
+            path,
+            output_stream=output_stream,
+            max_size=max_size,
+            args={
+                "timeout_ms": str(max_timeout_ms),
+            },
+            download_ratelimiter=download_ratelimiter,
+            ip_address=ip_address,
+        )
+
 
 def _create_path(federation_prefix: str, path: str, *args: str) -> str:
     """
diff --git a/synapse/federation/transport/server/__init__.py b/synapse/federation/transport/server/__init__.py
index edaf0196d6..c44e5daa47 100644
--- a/synapse/federation/transport/server/__init__.py
+++ b/synapse/federation/transport/server/__init__.py
@@ -32,8 +32,8 @@ from synapse.federation.transport.server._base import (
 from synapse.federation.transport.server.federation import (
     FEDERATION_SERVLET_CLASSES,
     FederationAccountStatusServlet,
+    FederationMediaDownloadServlet,
     FederationUnstableClientKeysClaimServlet,
-    FederationUnstableMediaDownloadServlet,
 )
 from synapse.http.server import HttpServer, JsonResource
 from synapse.http.servlet import (
@@ -316,11 +316,8 @@ def register_servlets(
             ):
                 continue
 
-            if servletclass == FederationUnstableMediaDownloadServlet:
-                if (
-                    not hs.config.server.enable_media_repo
-                    or not hs.config.experimental.msc3916_authenticated_media_enabled
-                ):
+            if servletclass == FederationMediaDownloadServlet:
+                if not hs.config.server.enable_media_repo:
                     continue
 
             servletclass(
diff --git a/synapse/federation/transport/server/_base.py b/synapse/federation/transport/server/_base.py
index 4e2717b565..e124481474 100644
--- a/synapse/federation/transport/server/_base.py
+++ b/synapse/federation/transport/server/_base.py
@@ -362,7 +362,7 @@ class BaseFederationServlet:
                                 return None
                             if (
                                 func.__self__.__class__.__name__  # type: ignore
-                                == "FederationUnstableMediaDownloadServlet"
+                                == "FederationMediaDownloadServlet"
                             ):
                                 response = await func(
                                     origin, content, request, *args, **kwargs
@@ -374,7 +374,7 @@ class BaseFederationServlet:
                     else:
                         if (
                             func.__self__.__class__.__name__  # type: ignore
-                            == "FederationUnstableMediaDownloadServlet"
+                            == "FederationMediaDownloadServlet"
                         ):
                             response = await func(
                                 origin, content, request, *args, **kwargs
diff --git a/synapse/federation/transport/server/federation.py b/synapse/federation/transport/server/federation.py
index 67bb907050..ec957768d4 100644
--- a/synapse/federation/transport/server/federation.py
+++ b/synapse/federation/transport/server/federation.py
@@ -790,7 +790,7 @@ class FederationAccountStatusServlet(BaseFederationServerServlet):
         return 200, {"account_statuses": statuses, "failures": failures}
 
 
-class FederationUnstableMediaDownloadServlet(BaseFederationServerServlet):
+class FederationMediaDownloadServlet(BaseFederationServerServlet):
     """
     Implementation of new federation media `/download` endpoint outlined in MSC3916. Returns
     a multipart/mixed response consisting of a JSON object and the requested media
@@ -798,7 +798,6 @@ class FederationUnstableMediaDownloadServlet(BaseFederationServerServlet):
     """
 
     PATH = "/media/download/(?P<media_id>[^/]*)"
-    PREFIX = FEDERATION_UNSTABLE_PREFIX + "/org.matrix.msc3916"
     RATELIMIT = True
 
     def __init__(
@@ -858,5 +857,5 @@ FEDERATION_SERVLET_CLASSES: Tuple[Type[BaseFederationServlet], ...] = (
     FederationV1SendKnockServlet,
     FederationMakeKnockServlet,
     FederationAccountStatusServlet,
-    FederationUnstableMediaDownloadServlet,
+    FederationMediaDownloadServlet,
 )