Forwarding Celery task events to Socket.IO in a FastAPI app

Tue, 13 Oct 2026 22:58:04 +0900

In a FastAPI app that hands long-running jobs, such as training a model, to Celery workers, clients usually want to know how their task is doing: when it starts, how far along it is, and when it succeeds or fails. One way to do this is to build a feedback system of one’s own, with a dedicated queue in RabbitMQ that workers publish to and the API consumes. Celery already has such a mechanism, though: task events, which workers send through the broker and which anyone connected to it can receive. This article shows how to emit custom progress events from a task and forward all task events to clients with Socket.IO.

Verifying OIDC access tokens in FastAPI with JWKS

Sat, 13 Sep 2025 11:00:00 +0900

When a frontend authenticates its users with an OIDC identity provider, it typically calls its backend API with the user’s access token in the Authorization: Bearer header. Before trusting the claims in that token, the API needs to verify its signature using the public keys of the identity provider, which are published at the provider’s JWKS (JSON Web Key Set) endpoint. Since this has to be done in every API that sits behind the identity provider, I packaged the verification logic as a FastAPI dependency, fastapi-oidc-jwks, published on PyPI.

FastAPI on Maxime Moreillon

Forwarding Celery task events to Socket.IO in a FastAPI app

Verifying OIDC access tokens in FastAPI with JWKS