Re: [pcp] pmrep: handle known/duplicate derived metrics

[Ken McDonell <kenj@xxxxxxxxxxxxxxxx>]

On 07/12/15 17:03, Marko Myllynen wrote:
> ...
> --- a/src/pmrep/pmrep.py
> +++ b/src/pmrep/pmrep.py
> @@ -61,7 +61,7 @@ import os
>   import re
>
>   from pcp import pmapi, pmgui, pmi
> -from cpmapi import PM_CONTEXT_ARCHIVE, PM_CONTEXT_HOST, PM_CONTEXT_LOCAL, 
> PM_MODE_FORW, PM_MODE_INTERP, PM_ERR_TYPE, PM_ERR_EOL, PM_IN_NULL, 
> PM_SEM_COUNTER, PM_TIME_MSEC, PM_TIME_SEC, PM_XTB_SET
> +from cpmapi import PM_CONTEXT_ARCHIVE, PM_CONTEXT_HOST, PM_CONTEXT_LOCAL, 
> PM_MODE_FORW, PM_MODE_INTERP, PM_ERR_TYPE, PM_ERR_EOL, PM_ERR_NAME, PM_IN_NULL, 
> PM_SEM_COUNTER, PM_TIME_MSEC, PM_TIME_SEC, PM_XTB_SET
>   from cpmapi import PM_TYPE_32, PM_TYPE_U32, PM_TYPE_64, PM_TYPE_U64, 
> PM_TYPE_FLOAT, PM_TYPE_DOUBLE, PM_TYPE_STRING
>   from cpmgui import PM_REC_ON, PM_REC_OFF, PM_REC_SETARG
>
> @@ -618,7 +618,12 @@ class PMReporter(object):
>                       err = ""
>                       try:
>                           name, expr = definition.split("=")
> -                        self.context.pmRegisterDerived(name.strip(), 
> expr.strip())
> +                        self.context.pmLookupName(name.strip())
> +                    except pmapi.pmErr as error:
> +                        if error.args[0] == PM_ERR_NAME:
> +                            self.context.pmRegisterDerived(name.strip(), 
> expr.strip())
> +                            continue
> +                        err = error.message()
>                       except ValueError as error:
>                           err = "Invalid syntax (expected metric=expression)"
>                       except Exception as error:
The check may be less necessary after my next commit (tomorrow probably) 
... I have added a check below pmRegisterDerived() to reject attempts to 
define a derived metric with a name that collides with a real metric 
(this test can only be done with an open context as that is where you 
need to check for the name of the metric being defined ... so it may 
happen at the pmNewContext() if there is no context when 
pmRegisterDerived() is called).