DataOps-platform/migrations/versions/20260818_557_plugin_final_downgrade_fence.py

"""Fence the first WP13 downgrade against every durable plugin fact."""

from alembic import op

revision = "20260818_557"
down_revision = "20260818_556"
branch_labels = None
depends_on = None


_FACT_TABLES = (
    # Registry rows carry the persisted review actor and incident link.
    "plugin_registry_versions",
    "plugin_approvals",
    "plugin_runtime_leases",
    "plugin_runs",
    "plugin_dead_letters",
    "plugin_audit_outbox",
    "plugin_request_claims",
    "plugin_runtime_breakers",
    "plugin_recovery_claims",
)


def upgrade() -> None:
    # This revision intentionally changes no successful runtime behaviour.  It
    # owns the first downgrade step so later revisions cannot expose 556's
    # narrower downgrade checks while any durable WP13 evidence still exists.
    op.get_bind().exec_driver_sql("SELECT 1")


def downgrade() -> None:
    bind = op.get_bind()
    checks = " OR ".join(
        f"EXISTS(SELECT 1 FROM public.{table} LIMIT 1)" for table in _FACT_TABLES
    )
    if bind.exec_driver_sql(f"SELECT {checks}").scalar():
        raise RuntimeError("downgrade refused: durable WP13 plugin facts are nonempty")