Vue 3 + TypeScript + Vite Component Library Starter

Steps

Scaffold the project

cd my-project-folder
# Scaffold directly into the folder
npm create vite@latest . -- --template vue-ts
# Install dependencies
npm install

# Include node types which are needed whenever you need to import from node
npm i --save-dev @types/node

## Update `package.json`
- Change name to `@username/projectname` to publish into your user scope.
- Remove `"private": true,` to allow publishing
- Specify `vue` as a peer dependency.

```json
  "peerDependencies": {
    "vue": "^3.0.0"
  },

• Add dist and optionally src to files to be published.

  "files": [
    "dist",
    "src"
  ],

• Add author, license, repository, keywords for package information.

  "author": "your-user-name",
  "license": "MIT",
  "repository": {
    "type": "git",
    "url": "git+https://github.com/your-user-name/your-repo-name.git"
  },
  "keywords": [
    "vue"
  ],

• Add exports fields to indicate how the package can be imported. Also mentions how types can be loaded.

  "exports": {
    ".": {
      "types": "./dist/types/index.d.ts",
      "import": "./dist/your-component-name.es.js",
      "require": "./dist/your-component-name.umd.js"
    },
    "./style.css": "./dist/your-component-name.css"
  }

Update vite.config.ts

Add the build config. An important setting includes emptyOutDir, which means do not clean the dist folder when building JS files by Vite. This is because we let vue-tsc emit the type declarations and let Vite emit the JS files.

import { defineConfig } from 'vite'
import vue from '@vitejs/plugin-vue'
import path from "path";

// https://vite.dev/config/
export default defineConfig({
  plugins: [vue()],
  build: {
    lib: {
      entry: path.resolve(__dirname, "src/index.ts"),
      name: "YourComponentName",
      fileName: (format) => `your-component-name.${format}.js`,
    },
    rollupOptions: {
      external: ["vue"],
      output: {
        exports: "named",
        globals: {
          vue: "Vue",
        },
      },
    },
    emptyOutDir: false, // to retain the types folder generated by tsc
  },
})

Since Vite will not help to empty out the folder, we need to update package.json to help do that.

    "build": "rm -rf dist && vue-tsc -b && vite build",

Add index.ts

Include an entry point, to allow it to be both used globally or individually.

import type { App } from "vue";
import HelloWorld from "./components/HelloWorld.vue";

export { HelloWorld };

export default {
  install(app: App) {
    app.component("HelloWorld", HelloWorld);
  },
};

Update tsconfig.app.json

The tsconfig.app.json is the one that we intend to use for building our component. The tsconfig.node.json is for any other development TypeScript files.

Set "noEmit": false so that type declarations can be emitted. This is set to true by default in the base config that we extend from. Other important settings include "emitDeclarationOnly": true to only emit type files.

{
  "extends": "@vue/tsconfig/tsconfig.dom.json",
  "compilerOptions": {
    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",

    /* Linting */
    "strict": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noFallthroughCasesInSwitch": true,
    "noUncheckedSideEffectImports": true,

    /* Type Declaration */
    "noEmit": false, // This is important to generate type declaration files
    "emitDeclarationOnly": true, // This prevents the generation of JS files, which is left to vite
    "declaration": true,
    "declarationMap": true,
    "outDir": "dist/types",
    "rootDir": "src"
  },
  "include": ["src/**/*.ts", "src/**/*.tsx", "src/**/*.vue"],
  "exclude": ["node_modules", "dist"]
}

Remove unused files

Remove the default files that are not needed, e.g., App.vue, main.ts, style.css, src/assets/, index.html.

Publish

# Update version in package.json as needed
npm run build
npm publish --access public

Usage

Make sure to import the style.css if your component contains css styles.

import { YourComponentName } from '@user-name/your-component-name'
import '@user-name/your-component-name/style.css'