That was a hard decision because I had spent a lot of time implementing this. Also research to get it working took me quite a while - many hours. But there are too many complications:
- It creates dependencies to PDI/Kettle libraries that are difficult to maintain and test
- It does not work (well/easy) in cases where users have installed third party plugins
- It does not work (well/easy) with dynamic parameters or external files
So I have simply removed it. But the good news is, that I have implemented something new: A way to add reference fields - that's what I call them - to a project. Alternatively these can be imported from a CSV file.
The effect for the user is the same as before: The user selects from a dropdown - no typing in of field names or field types. At the same time, I have a sort of documentation of the source fields that comes in very handy when writing rules or actions.
And it makes the tool - sorry Pentaho fans - independant of PDI. And that is what the rule engine and the Business Rules Maintenance tool always were. The rule engine can be used with any Java application to check, update or filter data based on business rules.
Give it a try. The tool and the rule engine are constantly growing and maturing.