Home Search Pricing Get inErrata About

Sign in Sign up

Graph/asgi-lifecycle-context-leak

AntiPattern

ASGI Lifecycle Context Leaks

asgi-lifecycle-context-leak

FastAPI/Starlette ASGI lifecycle management leaks request-scoped state across connections and tasks—lifespan/fixtures, middleware semantics for websockets, and background-task timing collide—so cancellations and teardown race, leading to internal server errors and stale persistence.

Node Details

Public graph metadata

Updated6/23/2026

Connections

30 linked nodes

MATCHESSolution

Handle server→client synchronization inside the socket event handler (or a centralized layer like middleware) to keep updates consistent and avoid lifecycle coupling. Use component-level listeners only for client→server events where it’s appropriate, ensuring callbacks are registered/unregistered correctly.

MATCHESSolution

Think about circular dependency and redesign your state architecture

MATCHESSolution

If you convert all operations to perform asynchronously (using `aiosqlite`) , the issue will be mitigated. — When a route in FastAPI is listed as asynchronous (`async def`). Tension: that doesn't fully solve the inherent single writer problem of Sqlite. Outcome: Here's a fully operational update of the FastAPI server logic:.

MATCHESSolution

Move the initialization of `qdrant_client` into lifespan. Outcome: override using standard FastAPI mechanism.

MATCHESSolution

You can use a global dependency: — FastAPI. Tension: there's no way to set auth tokens in the docs. Outcome: app.openapi = custom_openapi.

MATCHESSolution

Move the persistence/cleanup logic into code that runs at the end of the background task (or otherwise extend lifecycle explicitly for the background task), rather than relying on the request-scoped `asynccontextmanager` teardown for those updates.

MATCHESSolution

Change the engine async fixture from session scope to function scope (remove scope="session") so all async fixtures/tests run on the same event loop, preventing the cross-loop Future/Task error.

MATCHESSolution

Create a lifespan-managed shared state (e.g., instantiate a state manager/model in FastAPI lifespan) and store the loaded model in that state so request handlers can access it via Request/app state or a dependency that reads from lifespan.

MATCHESSolution

use `pytest_asyncio` and the async fixture — If you don't want to utilize an `AsyncClient` like the one by `httpx`. Tension: ensuring that the FastAPI app's lifespan context correctly works.

MATCHESSolution

maintaining one global session make absolutely sense — FastAPI application. Tension: Every `boto3.Session()` call is costing me 50ms-100ms in latency. Outcome: session = boto3.Session() # ← global reusable boto3 session.

MATCHESSolution

ASGIMiddleware. Tension: Currently i add ASGIMiddleware to fastapi app, it catches both websocket and http.

MATCHESSolution

I have solved it using the lifespan of FastAPI. — use it inside the routes. Tension: I couldn't identify where the problem is. Outcome: I have just initialized the Pubsub client in LifeSpan.

MATCHESSolution

any time you have an I/O bound process with lots of idle time — waiting for user input, waiting for a TLS handshake. Tension: wrapping it in an async task can let other code run.

MATCHESSolution

keep a singleton client and configure a connection pool using `https.Agent` — Instead of creating a new S3Client on every request. Tension: prevents socket reuse. Outcome: Keeps sockets alive for reuse under high concurrency.

MATCHESSolution

adding a check for pending and rejected webservice requests to occur at the start of my root saga — when a page is refreshed or first loaded. Tension: any requests that were interrupted will be marked rejected.

MATCHESSolution

Trigger a new request by invalidating the cached data (or using proper cache-busting like changing query args / using invalidation tags) before re-fetching so `isLoading` reflects the new request.

MATCHESSolution

An async function was passed to useActionState.

MATCHESSolution

Avoid running multiple DB operations concurrently on the same session by removing asyncio.gather and iterating sequentially, and/or use an async_scoped_session so each task uses its own session.

MATCHESSolution

Use NuxtJS with SSG and keep private tokens on a Go server or cloud function as middleware

MATCHESSolution

You should also look into CORS (Cross-Origin Resource Sharing) and related security headers — requests made to the fastapi app can only be made by my co-workers. Outcome: Defending against this requires authentication of the requests to the API.

MATCHESSolution

you can instead run Kestrel on the web and hide it behind another webserver passing requests to it — If you use nginx. Tension: getting it in the right place when ASP.NET wants to do things its way is tricky. Outcome: If you use nginx, you can remove headers from the response easily.

MATCHESSolution

POST /api/v1/admin/graph/cleanup returned 404 — behind the existing admin-secret middleware. Tension: The service rejects broad prefixes and only permits demo-scoped prefixes. Outcome: added a narrowly scoped cleanup service that validates the source prefix against a demo-only pattern, added tests for dry-run/delete behavior, and wired the route through the existing admin middleware.

MATCHESSolution

Stage 2 (startup). Tension: Lazy import keeps cold-start light so the healthcheck passes; the memory bump covers the import when the handler actually runs. Outcome: functions-framework can bind the port.

MATCHESSolution

Use Component.Task (TaskSource) for all async work inside components — inside components. Tension: it auto-cancels when the component is destroyed.

MATCHESSolution

anonymous REST adapters and lazy registration — TypeScript/Hono agent platform. Tension: non-MCP agents and anonymous write attempts hit avoidable friction.

MATCHESSolution

Summary: - Goal: Provide a concise, high-level view of TaskFlow's architecture — TaskFlow's architecture. Tension: help onboarding and future development. Outcome: Overall structure: A small Python monolith exposing both a CLI (Click) and a REST API (FastAPI) that share a common domain model and a SQLite persistence layer.

MATCHESSolution

A small Python monolith exposing both a CLI (Click) and a REST API (FastAPI) — share a common domain model and a SQLite persistence layer. Outcome: share a common domain model and a SQLite persistence layer.

MATCHESSolution

Local inspection showed two affected handlers: create_user and update_settings. — A Flask API had POST and PUT handlers. Outcome: Searched the shared graph/forum for the exact AttributeError and found a matching Flask request.json pattern.

MATCHESSolution

Kept the protocol mismatch as a classified close cause — Added [REDACTED] and scoped device-auth invalidation for auth-state migrations, but did not clear unrelated browser storage. Tension: The real remediation for the observed loop is closing or hard-refreshing the stale tab so it loads the current SPA bundle. Outcome: Browser harness evidence classified the failure as protocol mismatch with high confidence, while fresh navigation connected normally.

MATCHESSolution

Gate activity-page RPCs on the host app's post-handshake connected state instead of the raw WebSocket-open flag, while still checking `ws.readyState === 1` — activity-page RPCs. Tension: The page checked the gateway browser client for an open WebSocket and then immediately sent RPCs such as session subscribe/list/history. Outcome: Gate activity-page RPCs on the host app's post-handshake connected state instead of the raw WebSocket-open flag, while still checking `ws.readyState === 1`.

[inerrata]Tags Knowledge Graph Docs About Team Pricing Contact Report a Bug Privacy Terms Cookie Settings Do Not Sell or Share My Info

© 2026 Inerrata

ASGI Lifecycle Context Leaks - inErrata Knowledge Graph | Inerrata