For this guide we will be publishing a simple NPM typescript package called “npm-package-template-changesets” by using PNPM and the changesets cli. The automation part comes when we make any changes to the library, a bot will open a pull request that will require approval and will contain all the changes to be included in the new version as well as the changelog.
The package will support CJS for older versions and ESM.
1. Install PNPM and create a new project
This will generate a single package.json file, change the name property to a package name that doesn’t exist yet:
Also create a new repository on GitHub and add the url to the repository.url property, it’s important for provenance:
“name”: “npm-package-template-changesets”,
“repository”: {
“url”: “https://github.com/sebastianwd/npm-package-template-changesets”
},
“version”: “1.0.0”,
“description”: “”,
“main”: “index.js”,
“scripts”: {
“test”: “echo “Error: no test specified“ && exit 1″
},
“keywords”: [],
“license”: “ISC”
}
2. Install dependencies
tsup: used to build the typescript code, usage of this dep will depend on your use case
typescript: necessary dependency
@changesets/cli: used to for versioning and publishing
3. Generate tsconfig files
For this case we will use 2 tsconfig files: tsconfig.build.json and tsconfig.json. The difference between them is that tsconfig.build.json will use the properties composite: true and rootDir: “./src” so the build only looks at files in the src directory, while in development the tsconfig.json will override these settings and use rootDir”: “.” to enable typescript for config files at the root level.
tsconfig.build.json
“compilerOptions”: {
/* Base Options: */
“rootDir”: “./src”,
“esModuleInterop”: true,
“skipLibCheck”: true,
“target”: “es2022”,
“allowJs”: true,
“resolveJsonModule”: true,
“moduleDetection”: “force”,
“isolatedModules”: true,
“verbatimModuleSyntax”: true,
/* Strictness */
“strict”: true,
“noUncheckedIndexedAccess”: true,
“noImplicitOverride”: true,
“module”: “preserve”,
“outDir”: “dist”,
“sourceMap”: true,
“declaration”: true,
“composite”: true,
“noEmit”: true,
/* If your code doesn’t run in the DOM: */
“lib”: [
“es2022”
],
},
“include”: [
“src”
],
}
tsconfig.json:
“extends”: “./tsconfig.build.json”,
“compilerOptions”: {
“composite”: false,
“rootDir”: “.”
}
}
4. Add files to be published:
For this example, we will add a single index.ts file in the src directory:
index.ts
5. Update package.json:
Add scripts:
“build”: “tsup src”,
“release”: “changeset”,
“ci:publish”: “pnpm build && changeset publish –access public”
}
Add NPM config:
“provenance”: true,
“access”: “public”
}
Add entrypoints and type config in package.json:
“exports”: {
“.”: {
“types”: “./dist/index.d.ts”,
“import”: “./dist/index.mjs”,
“require”: “./dist/index.cjs”
}
},
“main”: “dist/index.cjs”,
“module”: “dist/index.mjs”,
“types”: “dist/index.d.ts”,
The require and main properties are for end users using CommonJS, which is older than ESM. ESM enables modern syntax and many benefits over CJS, but we will support both for this guide. For ESM the propeties module and import are the ones that apply.
To build files for both .cjs and .mjs extensions, we can use tsup:
tsup.config.ts
export default defineConfig({
entry: [“src/index.ts“],
splitting: false,
clean: true,
dts: true,
format: [“cjs“, “esm“],
outExtension({ format }) {
return {
js: format === “cjs“ ? “.cjs“ : “.mjs“,
};
},
});
6. Adding Github workflow file
.github/workflows/publish.yml
on:
push:
branches:
– master
concurrency: ${{ github.workflow }}-${{ github.ref }}
permissions:
contents: write
pull-requests: write
packages: write
id-token: write
jobs:
publish:
runs-on: ubuntu-latest
steps:
– uses: actions/checkout@v4
– uses: pnpm/action-setup@v4
with:
version: 9
– uses: actions/setup-node@v4
with:
node-version: 20.x
cache: “pnpm”
registry-url: “https://registry.npmjs.org”
– run: pnpm install –frozen-lockfile
– name: Create Release Pull Request or Publish
id: changesets
uses: changesets/action@v1
with:
publish: pnpm run ci:publish
env:
NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
The GITHUB_TOKEN is already present in the Github’s repository by default, the NPM_TOKEN value has to be generated in npm with publish permission:
Then, create a new repo on Github, go to Settings and add it to the secrets:
Also go to Actions > General
and enable this option or changesets won’t be able to open PRs:
7. Generate first changeset
Init changesets:
Create a first commit:
git add .
git commit -m “first release”
Run changeset:
If you get an error about “Failed to find where HEAD diverged from main”, configure your base branch in .changeset/config.json
You will be prompted some options, for this example we will choose patch:
New files were created in the .changesets folder, for this first release we should amend them to the previous commit so we don’t add another one:
git commit -m “first release” –amend
8. Push to the repository
After the CI is done, check the Pull Requests tab on the repo, there should be one open
Review it and merge it.
9. Check your package on NPM
