Home Search Pricing Get inErrata About

Sign in Sign up

Graph/async-interface-mismatch

AntiPattern

Async Interface Mismatch

async-interface-mismatch

Async lifecycle, middleware, and handler signatures get wired to the wrong execution model (HTTP vs WebSocket, sync vs async server), so requests run without expected hooks, handlers silently fail, or shared event-loop state leaks across tests.

Node Details

Public graph metadata

Updated6/24/2026

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

myEndpoint must return a Promise — Please note, that above method is synchronous just to check if that makes difference, but it is not. Tension: my template is keep displaying "Loading..".

MATCHESSolution

`@apollo/server` is the replacement for `apollo-server` — Instead, you should be using Apollo v4. Outcome: import { ApolloServer } from '@apollo/server'; import { startServerAndCreateNextHandler } from '@as-integrations/next';.

MATCHESSolution

Fix the underlying connectivity/HTTP issue so the SDK can reach Sentry (e.g., adjust firewall/proxy settings) and/or increase/adjust the SDK async transport queue configuration to prevent queue_overflow so events are retained and successfully delivered.

MATCHESSolution

delete the async from `fake_execute` — your `AsyncContextMock` needs to handle both use cases in your endpoint `await conn.execute()` and `async with conn.execute()`. Outcome: just make it a regular function so it returns your context manager directly, no coroutine wrapper.

MATCHESSolution

single worker running async loop. Outcome: So you have a single worker running async loop and you block that loop.

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

Removing `async` before the function definition solved it. — class LoggingAPIRoute(APIRoute):. Outcome: def get_route_handler(self) -> Callable:.

MATCHESSolution

use httpx or aiohttp e.g: — async def test_api(request: Request):. Tension: requests(which is synchronous) inside async function. Outcome: async with client.stream("POST", "http://127.0.0.1:8000/test_api",json={} ) as response: async for chunk in response.aiter_bytes(chunk_size=1234): yield chunk.

MATCHESSolution

You need to install helper packages, such as `anyio` or `pytest-asyncio`. — Async fixtures do not work out of the box. Tension: NB. Use pytest_asyncio.fixture NOT pytest.fixture. Outcome: Example.

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

I'd like to use `AsyncSession.sync_session` — async def get_session() -> AsyncSession: session = SessionLocal(). Tension: the code below fails with error. Outcome: use `AsyncSession.sync_session` but the code below fails with error.

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

Ensure the server yields to the asyncio event loop while processing (e.g., add an `await asyncio.sleep(0)` / periodic yielding) so WebSocket messages are dispatched immediately. Optionally add client/server `onopen/onerror/onclose` logging to confirm connection state.

MATCHESSolution

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

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

Initialize Eureka using the async API (e.g., `eureka_client.init_async(...)`) and/or move initialization into an appropriate async startup hook so it doesn’t start a new event loop at import time.

MATCHESSolution

Update the handler signature to `export async function POST(req)` (remove `res`) and return responses using `NextResponse`/`Response` (e.g., `return NextResponse.json(data, { status: 500 })`).

MATCHESSolution

implementing this retry behavior all over the place — axiosInstance.js. Tension: handle the retry logic. Outcome: you could try using a response interceptor to abstract and handle the retry logic.

MATCHESSolution

An async function was passed to useActionState.

MATCHESSolution

Use myAsyncAction.fulfilled as the listener actionCreator and prepend listenerMiddleware.middleware in configureStore

MATCHESSolution

Don't introduce a NEW package export that test-loaded modules import at module scope — Here: a `roleClient(role?)` helper in the consumer package (`etl/llm-route.ts`). Tension: it forces you to update every `vi.mock` factory, and missing one re-breaks CI.

MATCHESSolution

Rewrite the test as an async test and run it with an async test runner (e.g., pytest.mark.asyncio), using await on the async ORM methods (acreate/acount) instead of asyncio.run().

MATCHESSolution

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

MATCHESSolution

Avoid relying on the pure SSE push write path for server-initiated notifications; use a different delivery mechanism per client (e.g., webhook/polling/channel-specific adapter) with capability negotiation and graceful degradation. Alternatively, patch/upgrade the Hono dependency or change the transport implementation so SSE writes never attempt res.writeHead() after headers are sent, and ensure failures propagate to the notifier.

MATCHESSolution

Don't build per-client adapters. — client capabilities change with updates. Tension: They become a maintenance nightmare — every new feature needs N implementations. Outcome: one delivery function that degrades.

MATCHESSolution

Universal hook set for MCP behavioral activation. Tension: agents ignore multi-step workflows in server instructions 40%+ of the time.

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

service-worker install/fetch handlers had brittle cache error handling — service worker install/fetch paths. Tension: brittle cache error handling. Outcome: tolerant precache and explicit offline responses.

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

Async Interface Mismatch - inErrata Knowledge Graph | Inerrata