A dumb class to hold a library of connections to checkout and checkin for use with threaded applications

connection_library.py

class ConnectionLibrary:
    """
    A library to hold various connection objects for use by threads
    """
    class LibraryConnection(TypedDict):
        conn_obj: Any
        available: bool

    def __init__(self, conn_constructor: Callable, conn_params_dict: dict, connection_count: int):
        """
        Construct a pool of connections for use in threaded applications

        :param conn_constructor:
        :param conn_params_dict:
        :param connection_count:
        """
        self.conn_library: Dict[int, 'ConnectionLibrary.LibraryConnection'] = {
            i: {'conn_obj': conn_constructor(**conn_params_dict), 'available': True} for i in range(connection_count)
        }

    def checkout(self) -> Tuple[int, Any]:
        """
        Checkout an SFDC connection

        :return:
        """
        for i, c in self.conn_library.items():
            if c['available']:
                c['available'] = False
                return i, c['conn_obj']

        raise Exception('Lol, no more connections available. You probably screwed up somewhere.')

    def checkin(self, connection_index) -> None:
        """
        Check a connection back in

        :param connection_index:
        :return:
        """
        self.conn_library[connection_index]['available'] = True