govoplan-datasources is GovOPlaN's provider-neutral data access layer. It owns the tenant catalogue, lifecycle, staging, immutable materializations, frozen states, schema and fingerprint metadata, provenance, and bounded reads.

The module deliberately separates two layers:

Datasources describe governed data that modules can consume consistently.
Connectors acquire data from external systems and expose provider origins.

Dataflow, Workflow, Reporting, Risk Compliance, and other consumers depend on Datasource contracts rather than connector implementations.

The first executable slice supports tabular static uploads, connector-backed live and cached sources, staging and promotion, refresh, immutable snapshots, explicit frozen states, previews, retirement, and atomic producer publication. Origin discovery retains each provider's source mode, structured health, and declared pushdown support. Live previews preserve the provider's effective row, serialized-byte, and elapsed-time limits and its redacted diagnostics. Producer modules can append a bounded tabular result or create a new static datasource through an idempotent capability. The publication ledger retains the producer run, output materialization, provenance, and replay identity. On PostgreSQL, a transaction-scoped advisory lock serializes each tenant, producer, and idempotency identity before any output side effect, so retries from multiple application or worker nodes resolve to one durable publication.

Tabular staging also evaluates governed quality rules and classifies schema changes before promotion. Blocking stages remain inspectable, and successful promotion preserves the exact policy hash and validation result in immutable materialization provenance. The supported contract is documented in docs/QUALITY_POLICY.md.

The contracts already model database, HTTP/REST, directory, file, feed, document, binary, directory, and stream sources so providers can be added without changing consumers. Larger durable artifact-backed publications remain a later storage-provider slice.

See docs/CONCEPT.md for ownership and lifecycle details.