Javascript ES6 TypeError Class constructor Client cannot be invoked without new

Question

I have a class written in Javascript ES6. When I try to execute nodemon command I always see this error TypeError: Class constructor Client cannot be invoked without 'new'

The full error is mentioned below:

/Users/akshaysood/Blockchain/fabricSDK/dist/application/Transaction.js:45
        return (0, _possibleConstructorReturn3.default)(this, (FBClient.__proto__ || (0, _getPrototypeOf2.default)(FBClient)).call(this, props));
                                                                                                                              ^

TypeError: Class constructor Client cannot be invoked without 'new'
    at new FBClient (/Users/akshaysood/Blockchain/fabricSDK/dist/application/Transaction.js:45:127)
    at Object.<anonymous> (/Users/akshaysood/Blockchain/fabricSDK/dist/application/Transaction.js:195:14)
    at Module._compile (module.js:641:30)
    at Object.Module._extensions..js (module.js:652:10)
    at Module.load (module.js:560:32)
    at tryModuleLoad (module.js:503:12)
    at Function.Module._load (module.js:495:3)
    at Module.require (module.js:585:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/Users/akshaysood/Blockchain/fabricSDK/dist/routes/users.js:11:20)

What I am trying to do is, I have created a class and then created an instance of that class. Then I am trying to export that variable.

The class structure is defined below:

class FBClient extends FabricClient{

    constructor(props){
        super(props);
    }

<<< FUNCTIONS >>>

}

How I am trying to export the variable ->

var client = new FBClient();
client.loadFromConfig(config);

export default client = client;

Answer 1

Hello @kartik,

In package.json you can use targets configuration with @babel/preset-env. set the esmodules as 'true'.

Below is the example how I am using in my file:

  "babel": {
    "presets": [
      [
        "@babel/preset-env",
        {
          "targets": {
            "esmodules": true
          }
        }
      ],
      "@babel/preset-react",
      "@babel/preset-flow"
    ],
    "plugins": [
      "@babel/plugin-proposal-class-properties"
    ]
  },

Hope it works! and if you need to know more about javascript, then you should join one of our Java certification class without any delay.

Thank You!!