Decision node EL function help

[Paul Chavez <pc...@verticalsearchworks.com>]

Hello,

I am trying to implement a workflow that optionally executes an action based on the existence of a configuration property. The property is a path to a script, so I figured I could use fs:exists() to 'convert' the parameter to a Boolean, and also validate the property at the same time.

Right now I have a decision node like this:

    <decision name="run_hive_script">
        <switch>
            <case to="hive_script">${fs:exists(wf:conf('wf_script_path'))}</case>
            <default to="cleanup"/>
        </switch>
    </decision>

However in this example if 'wf_script_path' is not specified I get the error 'Exception in ActionStartXCommand java.lang.IllegalArgumentException: Can not create a Path from an empty string'

Is there a generic EL function I can use that is not in the docs to get length of the string or something I can use to build a Boolean expression?

Thank you,
Paul Chavez