How to include modules in client side in typescript projects?-CodePudding

I'm making a typescript project for client side javascript code.

Before I was using typescript, I imported a module like this (this is vanilla js in es6)

import * as THREE from 'https://threejs.org/build/three.module.js';

but with typescript, I installed the module with npm install and then import it like this

import * as THREE from 'three';

Problem is, when I then run the compiled js code, I get this browser js error:

Uncaught TypeError: Failed to resolve module specifier "three". Relative references must start with either "/", "./", or "../".

since import * as THREE from 'three'; is now in the compiled js files.

How can I fix this?

Thanks

tsconfig.json

{
    "compilerOptions": {
        "outDir": "dist/",
        "rootDir": "./src",
        "sourceMap": false,
        "noImplicitAny": true,
        "moduleResolution": "Node",
        "resolveJsonModule": true,
        "module": "ESNext",
        "target": "ESNext",
        "lib": [
            "ESNext", "DOM"
        ],
        "allowJs": false,
        "alwaysStrict": true,
        "typeRoots": [
            "node_modules/@types"
        ]
    },
    "include": [
        "src/",
        "src/**/*.json"
    ],
    "exclude": [

    ]
}

CodePudding user response：

In order to use this on the client side, a bundler would be needed.

I suggest webpack or snowpack. Snowpack is new and has a lot of very cool features.

CodePudding user response：

This assumes you are using TypeScript to compile isolated ES modules destined for use in the browser, loaded in HTML tags like <script type="module" src="myCompiledModule.js">. From your question details, it sounds like this is the case.

Although not entirely straightforward, it's relatively simple to accomplish this:

In order to satisfy the compiler, make sure you have installed both typescript and @types/three:

npm install typescript @types/three

Then, add this path mapping to your ./tsconfig.json:

{
  ...
  "compilerOptions": {
    "baseUrl": ".",
    "paths": {
      "https://threejs.org/build/three.module.js": ["node_modules/@types/three"]
    },
    ...
  },
  ...
}

Here's the full config I'm using to test this:

{
  "compilerOptions": {
    "baseUrl": ".",
    "paths": {
      "https://threejs.org/build/three.module.js": ["node_modules/@types/three"]
    },
    "esModuleInterop": true,
    "exactOptionalPropertyTypes": true,
    "isolatedModules": true,
    "lib": [
      "esnext",
      "dom",
      "dom.iterable"
    ],
    "module": "esnext",
    "moduleResolution": "node",
    "noUncheckedIndexedAccess": true,
    "outDir": "dist",
    "strict": true,
    "target": "esnext",
    "useUnknownInCatchVariables": true
  },
  "include": [
    "./src/**/*"
  ]
}

Now, you'll have the correct types for THREE in the modules where it is imported using the specifier "https://threejs.org/build/three.module.js". For example, when I type THREE.Mesh, TypeScript IntelliSense shows me that it's this type:

class Mesh<TGeometry extends THREE.BufferGeometry = THREE.BufferGeometry, TMaterial extends THREE.Material | THREE.Material[] = THREE.Material | THREE.Material[]>

Here's the example module in my test:

./src/index.ts:

import * as THREE from 'https://threejs.org/build/three.module.js';
console.log(THREE);

Now, when you compile your project using tsc, you'll get this output, which is a valid ECMAScript module and will use the "three" module imported from the hosted URL:

./dist/index.js:

import * as THREE from 'https://threejs.org/build/three.module.js';
console.log(THREE);

CodePudding user response：

Package installed with NPM are usually located in the node_modules folder. This mean you could access the library via it's relative path:

import * as THREE from './node_modules/tree/build/three.module.js';