Node.js (JavaScript, TypeScript)

Pulumi supports JavaScript programs running on Node.js using any of the Current, Active and Maintenance LTS versions.

Because programs are just JavaScript, you may elect to write them in any manner you’d normally write Node.js programs. That includes TypeScript, CoffeeScript, or Babel, in addition to your favorite tools such as build systems, linters, or test frameworks.

INSTALL NODE.JS

Getting Started

The fastest way to get started in JavaScript is using a template. From an empty directory in which you’d like to create a new project:

$ mkdir myproject && cd myproject
$ pulumi new javascript

This will create a Pulumi.yaml project file, a package.json file for dependencies, and an index.js file, containing your program. The name of the directory is used as the project name in Pulumi.yaml.

Pulumi Programming Model

The Pulumi programming model includes a core concept of Input and Output values, which are used to track how outputs of one resource flow in as inputs to another resource. This concept is important to understand when getting started with JavaScript and Pulumi, and the Inputs and Outputs documentation is recommended to get a feel for how to work with this core part of Pulumi in common cases.

Entrypoint

Pulumi executes your program by loading the entrypoint file as a Node module: require("index.ts"). By default, Pulumi will load index.ts or index.js. Alternatively, if you specify main within your package.json, Pulumi will load that module instead:

{
    "name": "my-package",
    "version": "1.0.0",
    ...
    "main": "src/entry.ts"
}

Your entrypoint can either return a module object with properties for each stack output:

// create resources
...
exports.out = myResource.output;

// create resources
...
export const out = myResource.output;

Or alternatively, your entrypoint can export a top level `async` function that returns an object with members for each stack output. Pulumi will automatically call this function and await the result:

module.exports = async () => {
    // create resources
    return { out: myResource.output };
}

export = async () => {
    // create resources
    return { out: myResource.output };
}

Most Pulumi programs use the first option, but programs that need to do async work at the top level (such as calling getOutputValue) may find they want to use the second.

TypeScript

You can elect to write Pulumi programs in TypeScript to get additional verification and tooling benefits. As of version 0.15.0, Pulumi supports TypeScript natively so you don’t need to explicitly run tsc on your program before running pulumi

If you would like full control of the TypeScript build process, you can compile ahead of time, and point your package.json main entry point at the compiled JavaScript instead. If you do this, you can disable the automatic compilation of TypeScript files.

The fastest way to get started with Pulumi in TypeScript, is to use a template:

$ mkdir myproject && cd myproject
$ pulumi new typescript

This will auto-generate all the basic artifacts required to use TypeScript. If you prefer, you can instead run the following manual steps.

1. Update package.json

Update your package.json to look like the following (with your own values for name, version, etc.). This is what tells Node.js and NPM what packages you depend on, where to find your code’s entry points, and so on:

{
    "name": "my-package",
    "version": "1.0.0",
    "devDependencies": {
        "@types/node": "^12.0.0"
    },
    "dependencies": {
        ... as before ...
    }
}

You can customize this however you’d like, such as adding test scripts, npm package dependencies, etc. For more information on package.json, refer to the NPM documentation.

2. Install dependencies

Run npm install or yarn install to install the new development-time dependencies to your node_modules directory.

3. Create tsconfig.json

When using Pulumi’s built in TypeScript support, a tsconfig.json file is optional. However, defining one allows your to set additional TypeScript compiler options, for example not allowing implicit returns from a function. In addition, other tools like VS Code will use these settings to give you additional warnings at development time. Any options set in your tsconfig.json file will be picked up by Pulumi. We recommend creating a tsconfig.json file with the following settings:

{
    "compilerOptions": {
        "strict": true,
        "outDir": "bin",
        "target": "es2016",
        "module": "commonjs",
        "moduleResolution": "node",
        "sourceMap": true,
        "experimentalDecorators": true,
        "pretty": true,
        "noFallthroughCasesInSwitch": true,
        "noImplicitReturns": true,
        "forceConsistentCasingInFileNames": true
    },
    "files": [
        "index.ts"
    ]
}

You may customize this however you’d like, including the TypeScript settings that work for you. For information on additional settings, see the TypeScript documentation for tsconfig.json.

Tools like VS Code will give you completion lists, live error reporting and inline documentation help.

Disabling built in TypeScript support

When using the built in TypeScript support, Pulumi sets the following compiler settings, which may not be overridden:

target: “es6”,
module: “commonjs”,
moduleResolution: “node”,
sourceMap: “true”,

If you need to change any of these settings, you can disable the built in TypeScript support by changing your the runtime setting in Pulumi.yaml to look like the following:

runtime:
  name: nodejs
  options:
    typescript: false