get-state.ts

import { getTestnetRpcProvider, view } from '@near-js/client';

export default async function getState() {
  // initialize testnet RPC provider
  const rpcProvider = getTestnetRpcProvider();

  // call view method without parameters
  const result = await view({
    account: 'guest-book.testnet',
    method: 'getMessages',
    deps: { rpcProvider },
  });

  console.log(result);
}