JSFiddle - React, Tailwind, and code Playground

JavaScript

const serverObj = {
 something_special: 1,
 something_else: 2,
 another_thing: 3,
 server_name: 'Person Cassey',
};

class MySpecialClass {
 constructor(objectFromServer) {
   Object.assign(this, objectFromServer);
   this.clientProp = 'hello';
 }
 
 greet() {
  console.log("Hi, " + this.server_name);
 }
}

const myInstance = new MySpecialClass(serverObj);

myInstance.greet();