Transfer events

Display the events that occur during a transfer by sending a value to a random account

// Import the API & Provider and some utility functions

const { ApiPromise } = require('@polkadot/api');

// Import the test keyring (already has dev keys for Alice, Bob, Charlie, Eve & Ferdie)

const testKeyring = require('@polkadot/keyring/testing');

// Utility function for random values

const { randomAsU8a } = require('@polkadot/util-crypto');

// Some constants we are using in this sample

const ALICE = '5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY';

const AMOUNT = 10000;

async function main () {

// Create the API and wait until ready

const api = await ApiPromise.create();

// Create an instance of our testing keyring

// If you're using ES6 module imports instead of require, just change this line to:

// const keyring = testKeyring();

const keyring = testKeyring.default();

// Get the nonce for the admin key

const { nonce } = await api.query.system.account(ALICE);

// Find the actual keypair in the keyring

const alicePair = keyring.getPair(ALICE);

// Create a new random recipient

const recipient = keyring.addFromSeed(randomAsU8a(32)).address;

console.log('Sending', AMOUNT, 'from', alicePair.address, 'to', recipient, 'with nonce', nonce.toString());

// Do the transfer and track the actual status

api.tx.balances

.transfer(recipient, AMOUNT)

.signAndSend(alicePair, { nonce }, ({ events = [], status }) => {

console.log('Transaction status:', status.type);

if (status.isInBlock) {

console.log('Included at block hash', status.asInBlock.toHex());

console.log('Events:');

events.forEach(({ event: { data, method, section }, phase }) => {

console.log('\t', phase.toString(), `: ${section}.${method}`, data.toString());

});

} else if (status.isFinalized) {

console.log('Finalized block hash', status.asFinalized.toHex());

process.exit(0);

}

});

}

main().catch(console.error);