Re: [PATCH 17/20] python/qemu/qmp.py: Preserve error context on re-raise

[Philippe Mathieu-Daudé]

On 10/7/20 1:58 AM, John Snow wrote:
> Use the "from ..." phrasing when re-raising errors to preserve their
> initial context, to help aid debugging when things go wrong.
> 
> This also silences a pylint 2.6.0+ error.
> 
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  python/qemu/qmp.py | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/python/qemu/qmp.py b/python/qemu/qmp.py
> index 9223307ed81..d911999da1f 100644
> --- a/python/qemu/qmp.py
> +++ b/python/qemu/qmp.py
> @@ -181,10 +181,11 @@ def __get_events(self, wait: Union[bool, float] = 
> False) -> None:
>                  self.__sock.settimeout(wait)
>              try:
>                  ret = self.__json_read(only_event=True)
> -            except socket.timeout:
> -                raise QMPTimeoutError("Timeout waiting for event")
> -            except:
> -                raise QMPConnectError("Error while reading from socket")
> +            except socket.timeout as err:
> +                raise QMPTimeoutError("Timeout waiting for event") from err
> +            except Exception as err:
> +                msg = "Error while reading from socket"
> +                raise QMPConnectError(msg) from err
>              if ret is None:
>                  raise QMPConnectError("Error while reading from socket")
>              self.__sock.settimeout(None)
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>