Docker Hub Webhooks

Docker Hub (hub.docker.com) is Docker Inc.'s container image registry. A Docker Hub repository webhook is configured per repository (repository → Webhooks tab → name + destination URL → Create) and fires on a push to that repository.

Two things make Docker Hub unlike most providers in this repo, and both must be reflected in your handler:

1. There is no signature verification. None. No signature header, no shared secret, no HMAC, no timestamp, no token field, no auth option. The create form takes exactly two inputs — a name and a destination URL. You cannot verify that a POST came from Docker Hub.
2. There is no event type. Docker Hub webhooks have exactly one trigger — a push — and the payload carries no event, type or action field, and the request carries no X-...-Event header. Do not write switch (event.type). Route on repository.repo_name and push_data.tag.