"""No-op — historic FULL/SYSCOLLECTOR backfill moved to API layer

Revision ID: 020
Revises: 019
Create Date: 2026-05-19 17:30:00.000000

Original intent: UPDATE scans SET scan_type='WAZUH' WHERE scan_type IN
('FULL','SYSCOLLECTOR'). Postgres rejects this in the same alembic
transaction stream that added the WAZUH enum value (019), because
the new enum value is not visible to subsequent transactions on the
same connection until it has been fully committed.

Error: psycopg2.errors.UnsafeNewEnumValueUsage

Several workarounds were tried (op.execute COMMIT, autocommit isolation)
and either broke alembic_version tracking or only worked on specific
setups. To avoid further deployment fragility the cosmetic relabel was
moved to the API serializer instead — see app/routers/scans.py
list_scans / list_scan_summaries which map FULL+SYSCOLLECTOR to
'wazuh' before returning to the frontend.

Historic rows in DB stay as FULL/SYSCOLLECTOR. No data is lost, the
operator only ever sees the unified 'wazuh' label.

This migration intentionally does nothing so the migration chain
stays linear and 021/022 can still run.
"""
from alembic import op


revision = '020'
down_revision = '019'
branch_labels = None
depends_on = None


def upgrade() -> None:
    # No-op. See module docstring.
    pass


def downgrade() -> None:
    pass
