Unset - Configuration Editor

Larry O'Leary loleary at redhat.com
Tue Sep 11 17:09:59 UTC 2012


The unset also has a valid use-case when there is no default value. For
example, some properties that are set for a plug-in can either be empty
strings or simply undefined. If undefined, the default value is used in
the managed resource. If defined (even if empty string) the value gets
set in the managed resource to an empty string. For example, the as5
plug-in provides a configuration property check-valid-connection-sql
which by default is unset. In this case, unset means that this
datasource XML element will not appear in the datasource definition.
However, if you were to set unset to false and leave the value blank,
the value becomes defined in the datasource's definition as an empty
string which is needed for some datasources.

So, not only do we need the notion of `Default` but we also need
`Null`. 

On Tue, 2012-09-11 at 12:47 -0400, John Sanda wrote:
> I agree and understand that we need a way to reset a value back to its default. I think we should explore whether or not there is a better way, especially if there is a general consensus that the unset checkbox is confusing.
> 
> On Sep 11, 2012, at 12:18 PM, John Mazzitelli <mazz at redhat.com> wrote:
> 
> >> I have a question. Do we need the unset column at all? 
> > 
> > The unset checkbox has always been a problem since it can be confusing what it means.
> > 
> > However, we need a way to support being able to unset a value so it falls back to its default value (which most times is not an empty value). This unset checkbox was the way we implemented that requirement.
> > 
> > For example, how do you distinguish a property value that is set, but is an empty string versus a value that is not set and whose value therefore becomes a non-empty default value (an internal default value that the code would use if the property is not set)?
> 
> Not sure I understand. The editor renders a text field with a non-empty default value. I edit the field, changing it to an empty string. So is the problem knowing/remembering that I have actually edited that text field?
> > 
> > This is the problem the unset checkbox attempted to solve.




More information about the rhq-devel mailing list