Ingest Event

Ingest a pixel event from the JS snippet.

Public endpoint — called from client websites. No JWT auth required. Validated by the API key in the event payload. Returns 204 No Content (the snippet doesn't need a response body). A rejected event is still 204 so the snippet never errors; the reason is exposed in X-Lapis-Pixel-Rejected for anyone debugging an install.

The request path does no database or network work: the event is parsed, known-invalid keys are dropped, and everything else is handed to the per-process ingest workers (pixel_ingest_queue), which validate the key (cached), check the domain restriction, upsert the session, insert the event and run the CAPI forwarding hooks off the request thread. The beacon always gets its 204 within a millisecond, regardless of database latency. The rejection header is derived from the in-process key cache (PixelIngestQueue.rejection_reason): exact for cached keys, absent while a key is still being validated on the unverified lane.