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Set Up

Creating a new npm package

Start by creating a new empty npm package:

# mkdir project-name
# cd project-name
# npm init -y
Wrote to /Users/rmuller/Downloads/project-name/package.json:

{
  "name": "project-name",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

Adding mandatory metadata

Then, add the mandatory information to the new package.json file that was created. Specifically, jsii modules must have an author and repository setting (those are necessary to generate valid libraries for certain distribution points, such as Maven Central):

{
  "name": "project-name",
  "version": "1.0.0",
  "description": "A demonstration jsii library",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": {
    "name": "John Doe",
    "email": "john.doe@acme.com"
  },
  "repository": {
    "url": "https://github.com/acme/project-name.git"
  },
  "license": "ISC"
}

Important

Before publishing your work, be sure to review the Important License Information documentation.

Setting up the jsii configuration

Finish up the configuration by running jsii-config, and letting the assistant guide you through the process:

# npx jsii-config
? Target Languages (Press <space> to select, <a> to toggle all, <i> to invert selection)
❯◯ java
 ◯ python
 ◯ dotnet
...
Success!

Install Dependencies

Now, you're ready to install the basic tools into the packages' dependency closure. The exact instructions depend on the JavaScript package manager you want to be using:

# yarn add -D jsii jsii-pacmak
yarn add v1.22.10
info No lockfile found.
[1/4] 🔍  Resolving packages...
[2/4] 🚚  Fetching packages...
[3/4] 🔗  Linking dependencies...
[4/4] 🔨  Building fresh packages...
success Saved lockfile.
success Saved 66 new dependencies.
...
# npm install --save-dev jsii jsii-pacmak

added 107 packages, and audited 107 packages in 4s

39 packages are looking for funding
  run `npm fund` for details

found 0 vulnerabilities

Set up essential scripts

Finally, you might want to configure convenience scripts in your package.json file in order to facilitate working with your project:

{
  "name": "project-name",
  "version": "1.0.0",
  "description": "A demonstration jsii library",
  "main": "index.js",
  "scripts": {
    "build": "jsii",
    "build:watch": "jsii --watch",
    "package": "jsii-pacmak"
  },
  "keywords": []
  // ...
}

Those scripts have the following effect:

Script Description
build Compiles the project
build:watch Watches for file changes and recompiles as needed
package Generates libraries for all languages

Last update: 2021-09-24