Make channel threads visible to connection owners

backend/app/gateway/internal_auth.py

@@ -5,10 +5,12 @@ from __future__ import annotations
 import os
 import secrets
 from types import SimpleNamespace
+from typing import Any
 
 from deerflow.runtime.user_context import DEFAULT_USER_ID
 
 INTERNAL_AUTH_HEADER_NAME = "X-DeerFlow-Internal-Token"
+INTERNAL_OWNER_USER_ID_HEADER_NAME = "X-DeerFlow-Owner-User-Id"
 INTERNAL_AUTH_ENV_VAR = "DEER_FLOW_INTERNAL_AUTH_TOKEN"
 INTERNAL_SYSTEM_ROLE = "internal"
 
@@ -23,9 +25,12 @@ def _load_internal_auth_token() -> str:
 _INTERNAL_AUTH_TOKEN = _load_internal_auth_token()
 
 
-def create_internal_auth_headers() -> dict[str, str]:
+def create_internal_auth_headers(*, owner_user_id: str | None = None) -> dict[str, str]:
     """Return headers that authenticate trusted Gateway internal calls."""
-    return {INTERNAL_AUTH_HEADER_NAME: _INTERNAL_AUTH_TOKEN}
+    headers = {INTERNAL_AUTH_HEADER_NAME: _INTERNAL_AUTH_TOKEN}
+    if owner_user_id:
+        headers[INTERNAL_OWNER_USER_ID_HEADER_NAME] = owner_user_id
+    return headers
 
 
 def is_valid_internal_auth_token(token: str | None) -> bool:
@@ -36,3 +41,21 @@ def is_valid_internal_auth_token(token: str | None) -> bool:
 def get_internal_user():
     """Return the synthetic user used for trusted internal channel calls."""
     return SimpleNamespace(id=DEFAULT_USER_ID, system_role=INTERNAL_SYSTEM_ROLE)
+
+
+def get_trusted_internal_owner_user_id(request: Any) -> str | None:
+    """Return the owner override for a trusted internal request, if present.
+
+    The header is ignored for normal browser/API callers. It is only honored
+    after ``AuthMiddleware`` has validated the internal auth token and stamped
+    the synthetic internal user onto ``request.state.user``.
+    """
+    user = getattr(getattr(request, "state", None), "user", None)
+    if getattr(user, "system_role", None) != INTERNAL_SYSTEM_ROLE:
+        return None
+
+    owner_user_id = request.headers.get(INTERNAL_OWNER_USER_ID_HEADER_NAME)
+    if not owner_user_id:
+        return None
+    owner_user_id = owner_user_id.strip()
+    return owner_user_id or None