Add sql lite session (#71)

I added an sql lite session generator.

Changes
The function `def get_session() -> Session` 
has changed to 
`def get_session(connect_to: ConfigProvider | str) -> Session`
If a JsonFileConfig Is given the postgress conection is checked.
If a string is given that starts with `sqlite:///` an sql db is created.
The use should otherwise be the same.

tests/utils/sql/connector_test.py

@@ -0,0 +1,80 @@
+import os.path
+from collections.abc import Generator
+from typing import Any
+from unittest.mock import Mock, patch
+
+import pytest
+from sqlalchemy.engine import Engine
+
+from aki_prj23_transparenzregister.config.config_providers import JsonFileConfigProvider
+from aki_prj23_transparenzregister.config.config_template import PostgreConnectionString
+from aki_prj23_transparenzregister.utils.sql.connector import (
+    get_pg_engine,
+    get_session,
+    init_db,
+)
+
+
+def test_get_engine_pg() -> None:
+    conn_args = PostgreConnectionString("", "", "", "", 42)
+    with patch(
+        "aki_prj23_transparenzregister.utils.sql.connector.sa.create_engine"
+    ) as mock_create_engine:
+        result = "someThing"
+        mock_create_engine.return_value = result
+        assert get_pg_engine(conn_args) == result
+
+
+@pytest.fixture()
+def delete_sqlite_table() -> Generator[str, None, None]:
+    """Cleans a path before and deletes the table after a test.
+
+    Returns:
+        The path where the sqlite table is placed.
+    """
+    sqlite_test_path = "test_db.db"
+    if os.path.exists(sqlite_test_path):
+        os.remove(sqlite_test_path)
+
+    yield sqlite_test_path
+
+    if os.path.exists(sqlite_test_path):
+        os.remove(sqlite_test_path)
+
+
+def test_get_sqlite_init(delete_sqlite_table: str) -> None:
+    """Tests if a sql table file can be initiated."""
+    assert not os.path.exists(delete_sqlite_table)
+    session = get_session(f"sqlite:///{delete_sqlite_table}")
+    init_db(session)
+    session.close()
+    engine = session.bind
+    assert isinstance(engine, Engine)
+    engine.dispose()
+    assert os.path.exists(delete_sqlite_table)
+
+
+@pytest.mark.parametrize("connection", ["faulty-name", 0, 9.2, True])
+def test_get_invalid_connection(connection: Any) -> None:
+    """Tests if an error is thrown on a faulty connections."""
+    with pytest.raises(TypeError):
+        get_session(connection)
+
+
+def test_init_pd_db() -> None:
+    """Tests if a pg sql database can be connected and initiated to."""
+    with patch(
+        "aki_prj23_transparenzregister.utils.sql.connector.get_pg_engine"
+    ) as mock_get_engine, patch(
+        "aki_prj23_transparenzregister.utils.sql.connector.declarative_base"
+    ) as mock_declarative_base:
+        mock_get_engine.connect.return_value = {}
+
+        mock_value = Mock()
+        mock_value.metadata.create_all.return_value = None
+        mock_declarative_base.return_value = mock_value
+
+        mock_value = Mock(spec=JsonFileConfigProvider)
+        mock_value.get_postgre_connection_string.return_value = ""
+
+        init_db(get_session(mock_value))

tests/utils/sql/entities_test.py

@@ -0,0 +1,4 @@
+def test_import() -> None:
+    from aki_prj23_transparenzregister.utils.sql import entities
+
+    assert entities