Javascript¶

This plugin allows execution of JavaScript code on streamed data using the GraalVM JavaScript engine.

Features¶

Execute JavaScript code on input data
Load JavaScript code from a file or provide it inline
Access input data from JavaScript
Emit output data from JavaScript

The JavaScript processor can also be configured to limit script execution time.

JavaScript API¶

The JavaScript code can access the input data passed to the processor.

The JavaScript code should define a process function that takes the input data and returns the output data:

function process(input) {
  // Process the input data
  return output;
}

Security Considerations¶

The JavaScript processor runs with limited permissions by default. It cannot access the file system, network, or other system resources unless explicitly allowed.

JAVAYAML

.processWith(JavaScriptConfigBuilder.builder()
    .withScript(value)
    .withScriptUrl(value)
)

processor:
  javascript:
    script: value
    scriptUrl: value

Java dependency management¶

Add this declaration to your dependency management system to access the configuration DSL for this plugin in Java.

MavenGradle

<dependency>
    <groupId>org.voltdb</groupId>
    <artifactId>volt-stream-plugin-javascript-api</artifactId>
    <version>1.0-20250910-124207-release-1.5.3</version>
</dependency>

implementation group: 'org.voltdb', name: 'volt-stream-plugin-javascript-api', version: '1.0-20250910-124207-release-1.5.3'

Properties¶

`script`¶

JavaScript code to execute Type: string

`scriptUrl`¶

URL to a JavaScript file to execute Type: string

Usage Examples¶

YAML

Capitalise all strings.

version: 1
name: JavaScriptProcessorExample

source:
  file:
    path: "input.txt"

pipeline:
  processors:
    - javascript:
        name: "js-processor"
        script: |
          function process(input) {
            if (typeof input === 'string') {
              return input.toUpperCase();
            }
            return input;
          }

sink:
  stdout: {}