[Ethereum] Sending Signed Transaction returns pending and event:undefined

ethereumjsreceiptssendrawtransactionweb3js

I am trying to send a signed transaction using web3 1.0 and Infura.io through the browser. When I run it I dont get any errors but the transaction never hits the blockchain so I am confused on whats happening.

*See the log below to see the details

<script src="https://cdn.jsdelivr.net/gh/ethereum/web3.js@1.0.0-beta.34/dist/web3.min.js"></script>
<script src="https://cdn.rawgit.com/ethereumjs/browser-builds/2fb69a714afe092b06645286f14b94f41e5c062c/dist/ethereumjs-tx.js"></script>

Here is the script – 

var web3 = new Web3();

if(web3.setProvider(new Web3.providers.HttpProvider('https://mainnet.infura.io/v3/API KEY'))){
web3.eth.net.isListening();
}

// Get Contract ABI
var abi = JSON.parse('MY ABI')

// Define Variable for Contract ABI
var AK = new web3.eth.Contract(abi);

// Set Contract Address
AK.options.address = "CONTRACT ADDRESS";

// Set amount 
var amountToSend = 100;
var weiAmount = amountToSend * 1e18;

// create transaction - to address, amount
var data = AK.methods.transfer("SEND TO ADDRESS", weiAmount).encodeABI();

// object to hold the transaction data From Address
web3.eth.getTransactionCount("SEND FROM ADDRESS").then(count => {  

// Set transaction params

let privateKey = new EthJS.Buffer.Buffer("FROM ADDRESS PRIVATE KEY", "hex")

web3.eth.getGasPrice().then(gasPrice => {

let txParams = {

nonce: web3.utils.toHex(count),

gasLimit: web3.utils.toHex(250000),

value: web3.utils.toHex(0),

gas: web3.utils.toHex(1000000), 

gasPrice: web3.utils.toHex(web3.eth.gasPrice),

to: "TO ADDRESS",

from: "FROM ADDRESS",

data: data

}

// Sign Transaction 
let tx = new EthJS.Tx(txParams)

tx.sign(privateKey)

let serializedTx = tx.serialize().toString('hex')

var receipt = web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'));

console.log('serializedTx:', serializedTx)
console.log('Receipt:', receipt)

});
});

When i run the script it logs – 

Promise {<pending>, _events: undefined, emit: ƒ, on: ƒ, once: ƒ, off: ƒ, …}
addListener: ƒ (t,e,r)
emit: ƒ (t,e,r,i,o,a)
listeners: ƒ (t,e)
off: ƒ (t,e,r,i)
on: ƒ (t,e,r)
once: ƒ (t,e,r)
removeAllListeners: ƒ (t)
removeListener: ƒ (t,e,r,i)
_events: undefined
__proto__: Promise
[[PromiseStatus]]: "pending"
[[PromiseValue]]: undefined

Best Answer

the sendSignedTransaction(...) returns a Promise (the same as getTransactionCount(...) above it). One way to get its result is to do it like:

web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'))
  .then( receipt => {
    console.log('Receipt:', receipt);
  })
  .catch(e => {
    console.error('Error broadcasting the transaction: ', e);
  });

The transaction won't be mined instantly. It will take anywhere from a few seconds to more than an hour (depending on your gas_price and network congestion) to have it mined and thus the result printed to console.

You can get the transaction hash before broadcasting it with:

const tx_hash = tx.hash().toString('hex')

And look for the transaction status on etherscan a few seconds/minutes after broadcasting it. If the tx is valid, it should show up as pending/confirmed.

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