Using es6 imports in Node.js

Node.js doesn't natively support ES6 imports. It uses CommonJS module system. However, Babel enables the use of ES6 modules in node. Babel basically transpiles all source files to ES5 and CommonJS so that it works natively.

Steps to run es6 in node

Installing babel

npm install @babel/core @babel/node --save-dev

Adding babel presets (Optional)

npm install @babel/preset-env --save-dev

Create a .babelrc file

  {
    "presets": [
      "@babel/preset-env"
    ]
  }

Add the babel-node start script to npm script in package.json

  "scripts": {
    "anyTaskName": "nodemon --exec babel-node src/mainModule.js",
    "test": "echo \"Error: no test specified\" && exit 1"
  }

Running npm script

Using the terminal, type the commmand to run the npm task added ('anyTaskName') to the 'scripts' in last step.

npm run anyTaskName

Steps to use VS code debugger

Installing babel

npm install @babel/core @babel/cli --save-dev

Add the babel compile script to npm script in package.json

  "scripts": {
       "build": "babel  src --out-dir out  --source-maps"
  }

Add debug configuration in launch.json

We can use preLaunchTask to transpile es6 before running

    {
      "type": "node",
      "request": "launch",
      "name": "Debug from Source Maps",
      "program": "${workspaceFolder}/out/index.js",
      "preLaunchTask": "npm: build",
    }