policy engine: ContextVars Python 3.12 fixes IN PROGRESS

Signed-off-by: John Andersen <[email protected]>

scitt_emulator/policy_engine.py

@@ -236,6 +236,7 @@
 from celery import Celery, current_app as celery_current_app
 from celery.result import AsyncResult
 from fastapi import FastAPI, Request
+from starlette.middleware.base import BaseHTTPMiddleware
 from pydantic import (
     BaseModel,
     PlainSerializer,
@@ -1722,6 +1723,13 @@ async def startup_fastapi_app_policy_engine_context(
         yield state
 
 
+class ContextVarMiddleware(BaseHTTPMiddleware):
+    async def dispatch(self, request: Request, call_next):
+        fastapi_current_app.set(request.app)
+        fastapi_current_request.set(request)
+        response = await call_next(request)
+        return response
+
 def make_fastapi_app(
     *,
     context: Optional[Dict[str, Any]] = None,
@@ -1732,6 +1740,7 @@ def make_fastapi_app(
             context,
         ),
     )
+    app.add_middleware(ContextVarMiddleware)
 
     @app.get("/rate_limit")
     async def route_policy_engine_status(
@@ -1751,8 +1760,6 @@ async def route_policy_engine_status(
         fastapi_request: Request,
     ) -> PolicyEngineStatus:
         global celery_app
-        fastapi_current_app.set(fastapi_request.app)
-        fastapi_current_request.set(fastapi_request)
         async with fastapi_request.state.no_celery_async_results_lock:
             request_task = AsyncResult(request_id, app=celery_app)
             request_task_state = request_task.state
@@ -1787,8 +1794,6 @@ async def route_request(
         request: PolicyEngineRequest,
         fastapi_request: Request,
     ) -> PolicyEngineStatus:
-        fastapi_current_app.set(fastapi_request.app)
-        fastapi_current_request.set(fastapi_request)
         # TODO Handle when submitted.status cases
         request_status = PolicyEngineStatus(
             status=PolicyEngineStatuses.SUBMITTED,