streams

Publish a new stream schema version

Schemas are immutable versions — this always creates version N+1. Re-validates every attached source's mapping against the new schema and returns the updated mapping statuses alongside it.

post/v1/streams/{streamId}/schema

Request

  • Base URL: https://postbag.dev
  • URL: https://postbag.dev/v1/streams/{streamId}/schema
  • Auth: HTTP bearer

Path parameters

streamIdstring required
Example:fm_8f3kq2

Request body

json_schemaobject required

JSON Schema draft 2020-12 describing the submission data. required drives drift detection and mapping completeness.

uiobject

Per-field rendering hints keyed by field name (label, placeholder, widget, options, order) — used to render embed snippets.

changelogstring

A short human note on what changed in this version, shown in the version history.

Response

published

Example response

{
  "schema": {
    "created_at": "2026-08-21T09:00:00.000Z"
  },
  "mappings": [
    {
      "id": "fm_8f3kq2",
      "form_id": "fm_8f3kq2"
    }
  ]
}

Changes

No recorded changes to this operation across all 1 revision of this API.