如何将 Vue 插件发布到 NPM 中？

Question

I wrote a very simple plugin for Voca.js by Typescript. You can find the source code here .

index.ts

import VueVoca from './vue-voca';
export {
    VueVoca
};

vue-voca.ts

import vue from 'vue';

export default {
  install(Vue: typeof vue) {
    Vue.prototype.$voca = require('voca');
  }
};

vue.d.ts

import Vue from 'vue';
import vc from 'voca';
declare module 'vue/types/vue' {
  export interface Vue {
    $voca: vc.VocaStatic;
  }
}

To create npm package I use this command

vue-cli-service build --name vue-voca --entry ./src/index.ts --target lib and npm pack .

package.json

{
  "name": "vue-voca",
  "version": "1.0.0",
  "private": false,
  "scripts": {
    "serve": "vue-cli-service serve ./example/main.ts --open",
    "build": "vue-cli-service build --name vue-voca --entry ./src/index.ts --target lib",
    "prepublishOnly": "npm run build"
  },
  "dependencies": {
    "@types/voca": "^1.4.0",
    "voca": "^1.4.0",
    "vue": "^2.6.7"
  },
  "devDependencies": {
    "@vue/cli-plugin-typescript": "^3.4.1",
    "@vue/cli-service": "^3.4.1",
    "fibers": "^3.1.1",
    "sass": "^1.17.2",
    "sass-loader": "^7.1.0",
    "typescript": "^3.3.3333",
    "vue-cli-plugin-component": "^1.10.5",
    "vue-template-compiler": "^2.6.7"
  },
  "files": [
    "dist/*.css",
    "dist/*.map",
    "dist/*.js",
    "src/*"
  ],
  "keywords": [
    "vue",
    "component"
  ],
  "types": "src/vue.d.ts",
  "typings": "src/vue.d.ts",
  "main": "dist/vue-services.umd.js",
  "module": "dist/vue-services.common.js"
}

tsconfig

{
  "compilerOptions": {
    "target": "es5",
    "module": "esnext",
    "strict": true,
    "jsx": "preserve",
    "declaration": true,  
    "importHelpers": true,
    "moduleResolution": "node",
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "sourceMap": true,
    "baseUrl": ".",
    "types": [
      "webpack-env"
    ],
    "paths": {
      "@/*": [
        "src/*"
      ]
    },
    "lib": [
      "esnext",
      "dom",
      "dom.iterable",
      "scripthost"
    ]
  },
  "include": [
    "src/**/*.ts",
    "src/**/*.tsx",
    "src/**/*.vue",
    "tests/**/*.ts",
    "tests/**/*.tsx"
  ],
  "exclude": [
    "node_modules"
  ]
}

But after using the npm package in another project I got an error. VueVoca does not recognize and Typescript can not work with it well.

webpack-internal:///./node_modules/vue/dist/vue.runtime.esm.js:620 [Vue warn]: Error in render: "TypeError: Cannot read property 'swapCase' of undefined"

found in

---> <HelloWorld> at src/components/HelloWorld.vue
       <App> at src/App.vue
         <Root>

Can anyone help me to write a correct plugin with a correct npm package?

Answer 1

The issue here is that you have written your plugin in TypeScript. So at a minimum, there are two type definitions:

• index.d.ts - Contains type definitions for index.ts file after compilation
• vue.d.ts - Contains your Vue.js module augmentation code for the Vue plugin.

Now your package.json has types/typings field is pointing to vue.d.ts . For TypeScript, when this library is imported, it infers the module augmentation code. It can never find at index.d.ts file. So, in your Vue component, this.$voca() will work with TS but not import { VueCoca } from 'vue-coca';

As a solution, set your types field to <PATH>/index.d.ts file. Also, rename vue.d.ts to augment.d.ts for the sake of brevity. The caller of this library should then write his own typings file - *.d.ts file where he will import this file like:

import 'vue-coca/<PATH>/augment.d';

Alternately, you can also import this augmentation file inside your plugin's main index.ts file. With this approach, users of this library will not have to include it separately.