Read

You can call functions in Smart Contract via "Call" RPC API. What you can call here is limited to view functions that is not changing any states in the Contract.

Import the ethers and @kaiachain/ethers-ext modules to add kaia features on ethers.js.

Set up the provider with the specified kairos testnet URL. A provider in ethers is a read-only abstraction to access the blockchain data.

Also, you can change the provider URL from kairos to quicknode

Set the Abi generated from solidity code

Define contract address to interact with

Create a contract instance with ethers.Contract, fill in params contractAddr, abi, provider. You can read and write the contract through this instance

Get the value of number from contract by using method counter.number()

SmartContractView.js

const ethers = require("ethers");

const provider = new ethers.providers.JsonRpcProvider("https://public-en-kairos.node.kaia.io");

/* compiled in remix.ethereum.org (compiler: 0.8.18, optimizer: false)

// SPDX-License-Identifier: UNLICENSED

pragma solidity ^0.8.13;

contract Counter {

uint256 public number;

event SetNumber(uint256 number);

constructor(uint256 initNumber) {

number = initNumber;

}

function setNumber(uint256 newNumber) public {

number = newNumber;

emit SetNumber(number);

}

function increment() public {

number++;

emit SetNumber(number);

}

}

*/

const abi = '[{"inputs":[{"internalType":"uint256","name":"initNumber","type":"uint256"}],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"number","type":"uint256"}],"name":"SetNumber","type":"event"},{"inputs":[],"name":"increment","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"number","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"newNumber","type":"uint256"}],"name":"setNumber","outputs":[],"stateMutability":"nonpayable","type":"function"}]';

const contractAddr = "0x95Be48607498109030592C08aDC9577c7C2dD505";

async function main() {

const counter = new ethers.Contract(contractAddr, abi, provider);

const number = await counter.number();

console.log("number", number.toString());

}

main();

output

❯ js SmartContractView.js

number 291