eventsubscribe.js

let Web3 = require("web3");
let artifacts = require("./abi.json");

const provider = new Web3.providers.WebsocketProvider(
  "wss://ws-mumbai.matic.today"
);
const web3 = new Web3(provider);

const rootContractInstance = new web3.eth.Contract(
  artifacts,
  "0x2E81cA2533C82caE6fca5D9b521FD9c46f8aa1Ba"
);

rootContractInstance.events
  .Data(
    {
      address: "0x2E81cA2533C82caE6fca5D9b521FD9c46f8aa1Ba",
    },
    function (error, event) {
      console.log(event);
    }
  )
  .on("connected", function (subscriptionId) {
    console.log(subscriptionId);
  })
  .on("data", function (event) {
    console.log(event); // same results as the optional callback above
  });