1.3 KiB
Tabular Source Preview Contract
Core defines provider-neutral DTOs for optional tabular source providers. A source declares whether it is live, cached, file-backed, or static; its schema and immutable fingerprint; structured health; and the exact projection, pagination, filter, aggregation, and sorting operations that the provider can push down. Consumers must not infer pushdown support from a provider name.
Every preview request carries independent row, byte, and elapsed-time budgets. A provider may tighten these values but must return its effective limits, returned byte count, elapsed milliseconds, truncation state, and structured diagnostics. Equivalent fields on the Datasources read request and result preserve that evidence when a live source is consumed through the catalogue. A row that cannot fit within the byte budget fails explicitly rather than leaking a partial value. Timeout, stale fingerprint, unavailable source, and authorization failures remain distinct provider-neutral errors.
Connector health and preview diagnostics must contain no credentials, endpoint userinfo, row values, or unbounded remote error bodies. A Datasource origin preserves this contract so registration and staging do not erase source mode, health, pushdown, or preview-limit evidence.