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');
const { typesBundleForPolkadot } = require('@crustio/type-definitions');
// 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({
provider: new WsProvider('ws://127.0.0.1:9944'),
typesBundle: typesBundleForPolkadot
});
// 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);