Gatling JS

Gatling JavaScript and Typescript DSL.

Project layout

• jvm: sbt project
  • jvm/adapter: Java code used by gatling-js
  • jvm/java2ts: TypeScript interfaces generation from Java code (used internally in gatling-js), see gatling/java2typescript for our fork of java2typescript, used here
• js: npm project with multiple workspaces for the different components of gatling-js
  • js/cli: CLI tool used by an end user to build/run/package gatling-js projects
  • js/jvm-types: generated TypesSript interfaces for Gatling Java (generated from jvm/java2ts)
  • js/core: Gatling Core module
  • js/http: Gatling HTTP module
• js-simulation: sample JavaScript simulation
• ts-simulation: sample TypeScript simulation

Also:

• tmp: where we copy npm packages to link to them from the sample simulation (see "Run the sample simulation locally" below).
• ~/.gatling: home directory for the CLI tool, where it downloads GraalVM and Coursier.

Code generated in jvm/java2ts needs to be copied to js/jvm-types (just use the script ./regen-java2ts.sh to generate, copy, format, and compile the code).

Requirements

For local development: JDK 21+, sbt, a recent version of node. To run a JS simulation using published artifacts: a recent version of node.

Run the sample simulation locally

This setup uses npm link to link the sample simulation project to locally built npm dependencies rather than downloading them from an npm registry.

TL;DR:

1. Install everything with ./install-all-with-links.sh, which:
   • publishes /jvm/adapter to your local repo
   • installs and builds the npm workspaces in js (note: the npm packages get copied to tmp)
   • installs and builds js-simulation
2. (When you change code in jvm/adapter or js, you can just rebuild everything with ./build-all.sh)
3. Run the sample simulation:

   cd js-simulation
   npm run start

How to use npm workspaces in /js

Examples:

• format code in all workspaces: npm run format --workspaces
• format code only in the core workspace: npm run format --workspace=core

Run the sample simulation

Configure the version of the @gatling.io dependencies in /js-simulation or /ts-simulation. Then:

npm install
npm run start

Questions, help?

Read the documentation.

Join the Gatling Community Forum.

Found a real bug? Raise an issue.