gateway/tests/unit/connectors/test_connectorDbPostgre_failLoud.py

# Copyright (c) 2026 Patrick Motsch
# All rights reserved.
"""Unit tests: PostgreSQL connector raises DatabaseQueryError on real failures.

Historical regression: ``getRecordset`` and friends used to swallow every
exception (``except Exception: log; return []``), which turned every kind of
broken query into "no rows found". That hid bugs like:

* dict passed where Postgres expected a UUID string ("can't adapt type 'dict'"),
* missing/renamed columns after an incomplete schema migration,
* dropped tables, lost connections, etc.

These tests pin the new contract: empty result sets still return ``[]`` /
``None`` (normal), but any exception inside the query path propagates as
``DatabaseQueryError`` with the table name attached. The transaction is
rolled back so the connection is usable for subsequent queries.
"""
from __future__ import annotations

from unittest.mock import MagicMock

import pytest
import psycopg2.errors

from modules.connectors.connectorDbPostgre import (
    DatabaseConnector,
    DatabaseQueryError,
    _rollbackQuietly,
)


class DummyTable:
    """Stand-in for a Pydantic model so we can drive the connector without a real DB.

    The connector reads ``model_class.__name__`` to derive the SQL table name,
    so the class name itself becomes the asserted table name in tests.
    """
    model_fields = {}


def _makeConnector(cursorBehavior):
    """Build a ``DatabaseConnector`` skeleton with mocked connection/cursor.

    ``cursorBehavior`` is a callable invoked with the cursor mock so the test
    can configure ``execute``/``fetchall``/``fetchone`` per scenario.
    """
    connector = DatabaseConnector.__new__(DatabaseConnector)
    cursor = MagicMock()
    cursorContext = MagicMock()
    cursorContext.__enter__ = MagicMock(return_value=cursor)
    cursorContext.__exit__ = MagicMock(return_value=False)

    connection = MagicMock()
    connection.cursor.return_value = cursorContext
    connector.connection = connection

    connector._ensureTableExists = MagicMock(return_value=True)
    connector._systemTableName = "_system"

    cursorBehavior(cursor)
    return connector, connection, cursor


class TestGetRecordsetFailLoud:
    def test_emptyResultStillReturnsList(self):
        """No rows → []; this is the normal happy path, not a failure."""
        def behavior(cursor):
            cursor.execute.return_value = None
            cursor.fetchall.return_value = []
        connector, connection, _ = _makeConnector(behavior)

        result = connector.getRecordset(DummyTable)
        assert result == []
        connection.rollback.assert_not_called()

    def test_dictAdaptErrorRaisesDatabaseQueryError(self):
        """Reproduces the Trustee bug: passing a dict in WHERE → can't adapt → raise."""
        def behavior(cursor):
            cursor.execute.side_effect = psycopg2.ProgrammingError(
                "can't adapt type 'dict'"
            )
        connector, connection, _ = _makeConnector(behavior)

        with pytest.raises(DatabaseQueryError) as excinfo:
            connector.getRecordset(
                DummyTable,
                recordFilter={"featureInstanceId": {"id": "uuid", "featureCode": "trustee"}},
            )

        assert excinfo.value.table == "DummyTable"
        assert "can't adapt type 'dict'" in str(excinfo.value)
        assert isinstance(excinfo.value.original, psycopg2.ProgrammingError)
        connection.rollback.assert_called_once()

    def test_missingColumnRaisesDatabaseQueryError(self):
        def behavior(cursor):
            cursor.execute.side_effect = psycopg2.errors.UndefinedColumn(
                'column "wat" does not exist'
            )
        connector, connection, _ = _makeConnector(behavior)

        with pytest.raises(DatabaseQueryError) as excinfo:
            connector.getRecordset(DummyTable, recordFilter={"wat": "x"})

        assert "wat" in str(excinfo.value)
        connection.rollback.assert_called_once()

    def test_operationalErrorRaisesDatabaseQueryError(self):
        """Connection lost mid-query is also a real failure that must propagate."""
        def behavior(cursor):
            cursor.execute.side_effect = psycopg2.OperationalError("connection lost")
        connector, connection, _ = _makeConnector(behavior)

        with pytest.raises(DatabaseQueryError):
            connector.getRecordset(DummyTable)
        connection.rollback.assert_called_once()


class TestGetRecordFailLoud:
    def test_recordNotFoundReturnsNone(self):
        """`fetchone()` returning None is "row missing", not an error."""
        def behavior(cursor):
            cursor.execute.return_value = None
            cursor.fetchone.return_value = None
        connector, connection, _ = _makeConnector(behavior)

        result = connector.getRecord(DummyTable, "missing-id")
        assert result is None
        connection.rollback.assert_not_called()

    def test_queryErrorRaisesDatabaseQueryError(self):
        def behavior(cursor):
            cursor.execute.side_effect = psycopg2.errors.UndefinedTable(
                'relation "DummyTable" does not exist'
            )
        connector, connection, _ = _makeConnector(behavior)

        with pytest.raises(DatabaseQueryError) as excinfo:
            connector.getRecord(DummyTable, "any-id")

        assert excinfo.value.table == "DummyTable"
        connection.rollback.assert_called_once()


class TestRollbackQuietly:
    def test_rollsBackOnLiveConnection(self):
        connection = MagicMock()
        _rollbackQuietly(connection)
        connection.rollback.assert_called_once()

    def test_swallowsRollbackError(self):
        """Rollback failure must not mask the original query error."""
        connection = MagicMock()
        connection.rollback.side_effect = RuntimeError("rollback failed")
        _rollbackQuietly(connection)

    def test_noopOnNoneConnection(self):
        _rollbackQuietly(None)