Script Connector

This is a community project that provides a connector. It is not officially supported by Camunda. Everybody is invited to contribute! A connector to evaluate scripts (i.e. script tasks) that are not written in FEEL. Scripts are useful for prototyping, to do (simple) calculations, or creating/modifying variables.

Usage

Legacy

The legacy connector provides compatibility with the previous implementation zeebe-script-worker.

The context does not offer access to job or zeebeClient anymore.

Example BPMN with service task:

<bpmn:serviceTask id="scripting" name="Evaluate the Script">
  <bpmn:extensionElements>
    <zeebe:taskDefinition type="script" />
    <zeebe:taskHeaders>
      <zeebe:header key="language" value="javascript" />
      <zeebe:header key="script" value="a + b" />
      <zeebe:header key="resultVariable" value="result" />
    </zeebe:taskHeaders>
  </bpmn:extensionElements>
</bpmn:serviceTask>

• the worker is registered for the type script
• required custom headers:
  • language - the name of the script language
  • script - the script to evaluate
  • resultVariable - the result of the evaluation is passed to this variable

Connector

The connector provides an element template that can be used to configure it.

Script languages

Available script languages are by default:

• javascript (GraalVM JS)
• groovy
• mustache
• kotlin

To register new script languages, you can use the ScriptEngineFactory to register any JSR-223 compliant script engine.

If you want to provide a non-compliant implementation, you can use the ScriptEvaluatorExtension SPI.

To register custom file extensions, you can use the LanguageProviderExtension SPI.

Install

Docker

For a local setup, the repository contains a docker-compose file. It starts a Zeebe broker and both (standalone and bundled) containers.

mvn clean package
cd docker
docker-compose up

Standalone Runtime

The docker image for the connector runtime is published as GitHub package.

docker pull ghcr.io/camunda-community-hub/script-connector/runtime:latest

Configure the connection to the Zeebe broker by setting the environment property ZEEBE_CLIENT_BROKER_GATEWAY-ADDRESS (default: localhost:26500)

The docker-compose file shows an example how this works.

Bundled Runtime

To run the connector inside the bundle, you can use the shaded jar.

The docker-compose file shows an example how this works.

Manual

Standalone Runtime

1. Download the runtime jar script-connector-runtime-{VERSION}.jar
2. Start the connector runtime java -jar script-connector-runtime-{VERSION}.jar

Bundled Runtime

1. Download the shaded connector jar script-connector-{VERSION}-shaded.jar
2. Copy it to your connector runtime.

Code of Conduct

This project adheres to the Contributor Covenant Code of Conduct. By participating, you are expected to uphold this code. Please report unacceptable behavior to [email protected].