Evaluate BPM step type

Evaluate an expression on some data and write the result to a data area or attribute.

By default, this only permits the data parameter. If you want to set other properties through parameters, you must explicitly permit them.

The script property identifies a JavaScript expression, e.g. "data.counter + 1". You can run complex expressions in a function, at its simplest something like

function(){return data.counter + 1;}()

You can set the script to a node in the properties using the "${script:binding}" syntax. Only the code of the script will be copied; bindings will not be available and any attempt to get them will result in null exceptions.

If you want to include a library scripts, you need to wrap the library scripts in a function, and put a comma between that and the evaluation. Global variables set by the library scripts will be visible to the evaluation script. Here is the example syntax:

"script": [ 
  "function(){",
  "${script:library1ScriptBinding}",
  "${script:library2ScriptBinding}",
  "}(),",
  "${script:evaluationScriptBinding}"
]