Python 3 exception convertion and re-raise

I have the following problem: my application is a bridge between dbus and json-rpc. I have a dbus library that in case of Dbus exception is raising a

DBusException("my err msg") exception.

My json-rpc library is catching all the Exception and convert it to a nice generic server error message

{"jsonrpc": "2.0", "error": {"code": -32000, "message": "Server error"}, "id": 2}

The problem is that i want to handle better those exceptions and I can distinguish between them only using the error message: for example I need to convert the

DBusException("Invalid Parameters")

to

{"jsonrpc": "2.0", "error": {"code": -32001, "message": "Server error", data="Invalid Parameters" }, "id": 2}

that can be done raising in my library an ApiError(msg, code, data) exception.

So summarizing: - I need to catch a DBusException - based on the err_msg I need to switch between different exception types and re-raise a modified ApiError exception

How is the better approach to that? this needs to be done in at least 10 functions that have the same exceptions.

1) using a decorator?

def my_exception_catcher(fun, *args, **kwargv):
    try:
        fun(args, *argv)
    except DBusException as e
        err_msg = str(e)
        if err_msg == "Invalid Arguments":
            raise ApiError("Server Error", code=1, data=err_msg)
        else if err_msg == "Connect Error":
            raise ApiError("Server Error", code=2, data=err_msg)
        else:
            raise

@my_exception_catcher
my_fun(*args):
    do_something

2) using a function to determine the exception type?

def find_my_dbus_error(err_msg):
    if err_msg == "Invalid Arguments":
        return ApiError("Server Error", code=1, data=err_msg)
    else if err_msg == "Connect Error":
        return ApiError("Server Error", code=2, data=err_msg)
    else:
        return Exception(err_msg)

try:
    my_fun(params)
except DBusException as e
    raise find_my_dbus_error(err_msg)

3) something else?

Thanks Nick