Re: [PATCH v2 07/17] python/aqmp: Disable logging messages by default

[Eric Blake]

On Wed, Sep 22, 2021 at 08:49:28PM -0400, John Snow wrote:
> AQMP is a library, and ideally it should not print error diagnostics
> unless a user opts into seeing them. By default, Python will print all
> WARNING, ERROR or CRITICAL messages to screen if no logging
> configuration has been created by a client application.
> 
> In AQMP's case, ERROR logging statements are used to report additional
> detail about runtime failures that will also eventually be reported to the
> client library via an Exception, so these messages should not be
> rendered by default.
> 
> (Why bother to have them at all, then? In async contexts, there may be
> multiple Exceptions and we are only able to report one of them back to
> the client application. It is not reasonably easy to predict ahead of
> time if one or more of these Exceptions will be squelched. Therefore,
> it's useful to log intermediate failures to help make sense of the
> ultimate, resulting failure.)
> 
> Add a NullHandler that will suppress these messages until a client
> application opts into logging via logging.basicConfig or similar. Note
> that upon calling basicConfig(), this handler will *not* suppress these
> messages from being displayed by the client's configuration.
> 
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  python/qemu/aqmp/__init__.py | 4 ++++
>  1 file changed, 4 insertions(+)

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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