refactor: 重构聊天模块支持 SSE 断线重连及用户上下文隔离

backend/src/v1/agent/router.py

@@ -48,6 +48,7 @@ from v1.users.dependencies import get_current_user
 router = APIRouter(prefix="/agent", tags=["agent"])
 logger = get_logger("v1.agent.router")
 _LAST_EVENT_ID_RE = re.compile(r"^\d+-\d+$")
+_RUN_ID_RE = re.compile(r"^[A-Za-z0-9_-]{1,128}$")
 _MAX_SSE_CONNECTIONS_PER_USER = 3
 _SSE_SLOT_TTL_SECONDS = 15 * 60
 _TERMINAL_RUN_EVENT_TYPES = {"RUN_FINISHED", "RUN_ERROR"}
@@ -120,6 +121,11 @@ def _is_terminal_run_event(event: dict[str, object]) -> bool:
     )
 
 
+def _is_target_run_event(event: dict[str, object], *, target_run_id: str) -> bool:
+    run_id = event.get("runId")
+    return isinstance(run_id, str) and run_id == target_run_id
+
+
 @router.post(
     "/runs", response_model=TaskAcceptedResponse, status_code=status.HTTP_202_ACCEPTED
 )
@@ -188,9 +194,19 @@ async def stream_events(
     thread_id: str,
     service: Annotated[AgentService, Depends(get_agent_service)],
     current_user: Annotated[CurrentUser, Depends(get_current_user)],
+    run_id: str | None = Query(default=None, alias="runId"),
     last_event_id: str | None = Header(default=None, alias="Last-Event-ID"),
     idle_limit: int = Query(default=300, ge=1, le=3600),
 ) -> StreamingResponse:
+    if run_id is None or _RUN_ID_RE.fullmatch(run_id) is None:
+        raise ApiProblemError(
+            status_code=422,
+            detail=problem_payload(
+                code="AGENT_INVALID_RUN_ID",
+                detail="Invalid runId",
+            ),
+        )
+
     if last_event_id is not None and (
         len(last_event_id) > 32 or _LAST_EVENT_ID_RE.fullmatch(last_event_id) is None
     ):
@@ -255,6 +271,8 @@ async def stream_events(
                     if not row_id or not isinstance(event, dict):
                         continue
                     cursor = row_id
+                    if not _is_target_run_event(event, target_run_id=run_id):
+                        continue
                     yield to_sse_event(row_id, event)
                     if _is_terminal_run_event(event):
                         terminal_event_reached = True