DataOps-platform/tests/test_database_migrations.py

from __future__ import annotations

import os
import subprocess
import uuid
from pathlib import Path

import psycopg2
import pytest
from sqlalchemy import create_engine, inspect
from sqlalchemy.engine import make_url


ROOT = Path(__file__).resolve().parents[1]
EXPECTED_BASELINE_TABLES = {
    "data_orders",
    "data_products",
    "metadata_review_records",
    "metadata_version_history",
    "task_list",
    "users",
}
EXPECTED_UPGRADED_TABLES = {
    "datasource_credentials",
    "datasource_credential_audit_events",
    "workflow_schedules",
    "workflow_runs",
    "workflow_task_runs",
    "workflow_engine_bindings",
    "workflow_plan_audits",
    "runner_task_executions",
    "workflow_canary_evidence",
    "workflow_gateway_operations",
    "workflow_migration_states",
    "workflow_dual_runs",
    "workflow_reconciliation_reports",
    "workflow_cutover_operations",
    "ingestion_sources",
    "source_artifacts",
    "ingestion_jobs",
    "evidence_fragments",
    "extraction_candidates",
    "data_elements",
    "data_element_versions",
    "candidate_decisions",
}


def test_data_research_ingestion_migration_is_additive_and_constrained():
    migration = (
        ROOT
        / "migrations"
        / "versions"
        / "20260722_100_data_research_ingestion.py"
    ).read_text(encoding="utf-8")

    assert 'revision = "20260722_100"' in migration
    assert 'down_revision = "20260719_90"' in migration
    for table in (
        "ingestion_sources",
        "source_artifacts",
        "ingestion_jobs",
        "evidence_fragments",
        "extraction_candidates",
    ):
        assert f"CREATE TABLE IF NOT EXISTS public.{table}" in migration
    assert "idempotency_key" in migration
    assert "parser_version" in migration
    assert "locator JSONB" in migration
    assert "DROP TABLE" not in migration.upper()


def test_data_element_migration_adds_versioned_governance_tables():
    migration = (
        ROOT
        / "migrations"
        / "versions"
        / "20260722_105_data_research_elements.py"
    ).read_text(encoding="utf-8")

    assert 'revision = "20260722_105"' in migration
    assert 'down_revision = "20260722_100"' in migration
    for table in ("data_elements", "data_element_versions", "candidate_decisions"):
        assert f"CREATE TABLE IF NOT EXISTS public.{table}" in migration
    assert "UNIQUE (data_element_uid, version)" in migration
    assert "DROP TABLE" not in migration.upper()


def test_alembic_configuration_is_environment_only():
    ini = (ROOT / "alembic.ini").read_text(encoding="utf-8")
    env = (ROOT / "migrations" / "env.py").read_text(encoding="utf-8")

    assert "sqlalchemy.url" not in ini
    assert "SQLALCHEMY_DATABASE_URI" in env
    assert "DATABASE_URL" in env
    assert "password" not in env.lower()


def test_baseline_migration_is_non_destructive():
    baseline = (
        ROOT / "migrations" / "versions" / "20260716_01_baseline.py"
    ).read_text(encoding="utf-8")

    assert "def upgrade" in baseline
    assert "def downgrade" in baseline
    assert "drop_table" not in baseline
    for table in EXPECTED_BASELINE_TABLES:
        assert table in baseline


@pytest.mark.integration
def test_alembic_upgrade_is_repeatable_and_downgrade_preserves_tables():
    admin_url = os.environ.get("TEST_POSTGRES_ADMIN_URL")
    if not admin_url:
        pytest.skip("TEST_POSTGRES_ADMIN_URL is not configured")

    parsed = make_url(admin_url)
    database_name = f"dataops_migration_{uuid.uuid4().hex[:12]}"
    target_url = parsed.set(database=database_name).render_as_string(
        hide_password=False
    )

    connection = psycopg2.connect(admin_url)
    connection.autocommit = True
    try:
        with connection.cursor() as cursor:
            cursor.execute(f'CREATE DATABASE "{database_name}"')

        env = os.environ.copy()
        env["SQLALCHEMY_DATABASE_URI"] = target_url
        command = [str(ROOT / ".venv" / "bin" / "alembic"), "-c", "alembic.ini"]

        subprocess.run(command + ["upgrade", "head"], cwd=ROOT, env=env, check=True)
        subprocess.run(command + ["upgrade", "head"], cwd=ROOT, env=env, check=True)

        engine = create_engine(target_url)
        try:
            tables = set(inspect(engine).get_table_names(schema="public"))
            assert EXPECTED_BASELINE_TABLES | {"alembic_version"} <= tables
            assert EXPECTED_UPGRADED_TABLES <= tables
        finally:
            engine.dispose()

        subprocess.run(command + ["downgrade", "-1"], cwd=ROOT, env=env, check=True)

        engine = create_engine(target_url)
        try:
            tables = set(inspect(engine).get_table_names(schema="public"))
            assert EXPECTED_BASELINE_TABLES <= tables
        finally:
            engine.dispose()
    finally:
        with connection.cursor() as cursor:
            cursor.execute(
                "SELECT pg_terminate_backend(pid) FROM pg_stat_activity "
                "WHERE datname = %s AND pid <> pg_backend_pid()",
                (database_name,),
            )
            cursor.execute(f'DROP DATABASE IF EXISTS "{database_name}"')
        connection.close()