Skip to main content

Script task

A Script Task is a BPMN flow element that executes a script within the process flow. It allows for custom logic, calculations, data transformations, and integrations to be performed using scripting languages.

Key characteristics​

  • Script execution: Script Tasks execute scripts written in supported scripting languages (JavaScript, Groovy, etc.) within the process engine.

  • Input and output parameters: Can access process variables as input and modify or create new variables as output.

  • Synchronous execution: Script Tasks are typically executed synchronously by process engines.

  • Error handling: Errors must be mapped to BPMN Error Events.

  • Expression evaluation: Can be used for simple expressions or complex multi-line scripts.

Usage patterns​

  • Data transformation: Use to manipulate process data, perform calculations, or format information.

  • Business logic execution: Implement custom business rules or decision logic that doesn't fit standard BPMN elements.

  • Variable manipulation: Set, modify, or compute process variables based on complex logic.

  • Validation and formatting: Validate data or format output for downstream processing.

Graphical notation​

A rectangle with a script icon (scroll/roll) in the top-left corner.

XML Definition​

<bpmn:scriptTask id="ScriptTask_1" name="Calculate Total" scriptFormat="javascript">
  <bpmn:incoming>Flow1</bpmn:incoming>
  <bpmn:outgoing>Flow2</bpmn:outgoing>
  <bpmn:script>
    <![CDATA[
      var total = execution.getVariable('price') * execution.getVariable('quantity');
      execution.setVariable('total', total);
    ]]>
  </bpmn:script>
</bpmn:scriptTask>

Current Implementation​