Add appservice user/device masquerading support to base HTTPAPI

mautrix/api.py

@@ -5,7 +5,7 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 from __future__ import annotations
 
-from typing import AsyncGenerator, ClassVar, Literal, Mapping, Union
+from typing import ClassVar, Literal, Mapping
 from enum import Enum
 from json.decoder import JSONDecodeError
 from urllib.parse import quote as urllib_quote, urljoin as urllib_join
@@ -28,7 +28,7 @@
 
 if __optional_imports__:
     # Safe to import, but it's not actually needed, so don't force-import the whole types module.
-    from mautrix.types import JSON
+    from mautrix.types import JSON, DeviceID, UserID
 
 API_CALLS = Counter(
     name="bridge_matrix_api_calls",
@@ -193,6 +193,13 @@ class HTTPAPI:
     default_retry_count: int
     """The default retry count to use if a custom value is not passed to :meth:`request`"""
 
+    as_user_id: UserID | None
+    """An optional user ID to set as the user_id query parameter for appservice requests."""
+    as_device_id: DeviceID | None
+    """
+    An optional device ID to set as the user_id query parameter for appservice requests (MSC3202).
+    """
+
     def __init__(
         self,
         base_url: URL | str,
@@ -203,6 +210,8 @@ def __init__(
         txn_id: int = 0,
         log: TraceLogger | None = None,
         loop: asyncio.AbstractEventLoop | None = None,
+        as_user_id: UserID | None = None,
+        as_device_id: UserID | None = None,
     ) -> None:
         """
         Args:
@@ -212,13 +221,19 @@ def __init__(
             txn_id: The outgoing transaction ID to start with.
             log: The :class:`logging.Logger` instance to log requests with.
             default_retry_count: Default number of retries to do when encountering network errors.
+            as_user_id: An optional user ID to set as the user_id query parameter for
+                appservice requests.
+            as_device_id: An optional device ID to set as the user_id query parameter for
+                appservice requests (MSC3202).
         """
         self.base_url = URL(base_url)
         self.token = token
         self.log = log or logging.getLogger("mau.http")
         self.session = client_session or ClientSession(
             loop=loop, headers={"User-Agent": self.default_ua}
         )
+        self.as_user_id = as_user_id
+        self.as_device_id = as_device_id
         if txn_id is not None:
             self.txn_id = txn_id
         if default_retry_count is not None:
@@ -360,6 +375,11 @@ async def request(
         query_params = query_params or {}
         if isinstance(query_params, dict):
             query_params = {k: v for k, v in query_params.items() if v is not None}
+        if self.as_user_id:
+            query_params["user_id"] = self.as_user_id
+        if self.as_device_id:
+            query_params["org.matrix.msc3202.device_id"] = self.as_device_id
+            query_params["device_id"] = self.as_device_id
 
         if method != Method.GET:
             content = content or {}