Asynchronous Uploads (#15503)

Support asynchronous uploads as defined in MSC2246.

changelog.d/15503.feature

@@ -0,0 +1 @@
+Add support for asynchronous uploads as defined by [MSC2246](https://github.com/matrix-org/matrix-spec-proposals/pull/2246). Contributed by @sumnerevans at @beeper.

docs/usage/configuration/config_documentation.md

@@ -1753,6 +1753,19 @@ rc_third_party_invite:
   burst_count: 10
 ```
 ---
+### `rc_media_create`
+
+This option ratelimits creation of MXC URIs via the `/_matrix/media/v1/create`
+endpoint based on the account that's creating the media. Defaults to
+`per_second: 10`, `burst_count: 50`.
+
+Example configuration:
+```yaml
+rc_media_create:
+  per_second: 10
+  burst_count: 50
+```
+---
 ### `rc_federation`
 
 Defines limits on federation requests.
@@ -1814,6 +1827,27 @@ Example configuration:
 media_store_path: "DATADIR/media_store"
 ```
 ---
+### `max_pending_media_uploads`
+
+How many *pending media uploads* can a given user have? A pending media upload
+is a created MXC URI that (a) is not expired (the `unused_expires_at` timestamp
+has not passed) and (b) the media has not yet been uploaded for. Defaults to 5.
+
+Example configuration:
+```yaml
+max_pending_media_uploads: 5
+```
+---
+### `unused_expiration_time`
+
+How long to wait in milliseconds before expiring created media IDs. Defaults to
+"24h"
+
+Example configuration:
+```yaml
+unused_expiration_time: "1h"
+```
+---
 ### `media_storage_providers`
 
 Media storage providers allow media to be stored in different

synapse/api/errors.py

@@ -83,6 +83,8 @@ class Codes(str, Enum):
     USER_DEACTIVATED = "M_USER_DEACTIVATED"
     # USER_LOCKED = "M_USER_LOCKED"
     USER_LOCKED = "ORG_MATRIX_MSC3939_USER_LOCKED"
+    NOT_YET_UPLOADED = "M_NOT_YET_UPLOADED"
+    CANNOT_OVERWRITE_MEDIA = "M_CANNOT_OVERWRITE_MEDIA"
 
     # Part of MSC3848
     # https://github.com/matrix-org/matrix-spec-proposals/pull/3848

synapse/config/ratelimiting.py

@@ -204,3 +204,10 @@ def read_config(self, config: JsonDict, **kwargs: Any) -> None:
             "rc_third_party_invite",
             defaults={"per_second": 0.0025, "burst_count": 5},
         )
+
+        # Ratelimit create media requests:
+        self.rc_media_create = RatelimitSettings.parse(
+            config,
+            "rc_media_create",
+            defaults={"per_second": 10, "burst_count": 50},
+        )

synapse/config/repository.py

@@ -141,6 +141,12 @@ def read_config(self, config: JsonDict, **kwargs: Any) -> None:
             "prevent_media_downloads_from", []
         )
 
+        self.unused_expiration_time = self.parse_duration(
+            config.get("unused_expiration_time", "24h")
+        )
+
+        self.max_pending_media_uploads = config.get("max_pending_media_uploads", 5)
+
         self.media_store_path = self.ensure_directory(
             config.get("media_store_path", "media_store")
         )

synapse/media/_base.py

@@ -83,6 +83,12 @@
     "audio/x-flac",
 ]
 
+# Default timeout_ms for download and thumbnail requests
+DEFAULT_MAX_TIMEOUT_MS = 20_000
+
+# Maximum allowed timeout_ms for download and thumbnail requests
+MAXIMUM_ALLOWED_MAX_TIMEOUT_MS = 60_000
+
 
 def respond_404(request: SynapseRequest) -> None:
     assert request.path is not None