[Pacemaker] pcs: Return code handling not clean

[Andreas Mock]

Hi Chris,

just seen in the github repo - which I found after posting here -
that you made a fix.

Thank you for the very fast reaction.

Best regards
Andreas

-----Ursprüngliche Nachricht-----
Von: Chris Feist [mailto:cfeist at redhat.com] 
Gesendet: Mittwoch, 17. April 2013 00:34
An: The Pacemaker cluster resource manager; Andreas Mock
Betreff: Re: [Pacemaker] pcs: Return code handling not clean

On 04/16/13 06:46, Andreas Mock wrote:
> Hi all,
>
> as I don't really know, where to address this issue, I do post it 
> here. On the one handside as an information for guys scripting with 
> the help of 'pcs' and on the other handside with the hope that one 
> maintainer is listening and will have a look at this.
>
> Problem: When cluster is down a 'pcs resource'
> shows an error message coming from a subprocess call of 'crm_resource 
> -L' but exits with an error code of 0. That's something which can be 
> improved. Especially while the python code does have error handling in 
> other paces.
>
> So I guess it is a simple oversight.
>
> Look at the following piece of code in
> pcs/resource.py:
>
> 915     if len(argv) == 0:
> 916         args = ["crm_resource","-L"]
> 917         output,retval = utils.run(args)
> 918         preg = re.compile(r'.*(stonith:.*)')
> 919         for line in output.split('\n'):
> 920             if not preg.match(line) and line != "":
> 921                 print line
> 922         return
>
> retval is totally ignored, while being handled on other places. That 
> leads to the fact that the script returns with status 0.

This is an oversight on my part, I've updated the code to check retval and
return an error.  Currently I'm not passing through the full error code (I'm
only returning 0 on success and 1 on failure).  However, if you think it
would be useful to have this information I would be happy to look at it and
see what I can do.  I'm planning on eventually having pcs interpret the
crm_resource error code and provide a more user friendly output instead of
just a return code.

Thanks,
Chris

>
> Interestingly the error handling of the utils.run call used all over 
> the module is IMHO a little bit inconsistent.
> If I remember correctly Andrew did some efforts in the past to have a 
> set of return codes comming from the base cibXXX and crm_XXX tools. (I 
> really don't know how much they are differentiated). Why not pass them 
> through?
>
> Best regards
> Andreas Mock
>
>
>
>
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