How to fetch created address from transaction hash

[yehia67]

Hello,
I am creating a private blockchain and use ethereum-lite-explorer to see the transactions. I need to deploy a smart contract and get his address. The deployment is done successfully but I get the address manually from ethereum-lite-explorer. I tried to use web3.eth.getTransaction but it didn't return the newly created address.

My code:

  static async deploy(contractName,args,private_key){  
 
    const filePath = path.resolve('build/contracts/'+contractName+'.json');
    let rawdata = fs.readFileSync(filePath);
    const  contractArtifacts = JSON.parse(rawdata); 
    const addressFrom = web3.eth.accounts.privateKeyToAccount(private_key).address;
    const bytecode = contractArtifacts.bytecode.substring(2);
    const contractData = EthCrypto.txDataByCompiled(
      contractArtifacts.abi, // abi
      bytecode, // bytecode
      args // constructor-arguments
  );
 
  const signed = await web3.eth.accounts.signTransaction({
    from:addressFrom,
    data: contractData,
    gasPrice: 0,
    gas:'0x1ffffffffffffe' ,
    nonce: await web3.eth.getTransactionCount(addressFrom, 'pending')
  }, private_key);
  const request ='{"jsonrpc":"2.0","method": "eth_sendRawTransaction", "params":["'+ signed.rawTransaction +'"],"id":1}';
  /* Send Signed Transaction*/
  const sendSignedTransaction = await curlCall.execute(request,URL); 
  console.log('transaction hash',sendSignedTransaction.result)
  const transaction = await web3.eth.getTransaction(sendSignedTransaction.result);
   return transaction;
  }

The output:

{ from: '0x630684Afd6eA1cC391682F229B02c1cAeEBBdB59',
  gas: 9007199254740990,
  gasPrice: '0',
  hash:
   '0x3fb519a9264beb74fb9d932313cbd40febba00ec3e31be7e263e53625d1d3fea',
  input:'<long input>',
  nonce: 15,
  to: null,
  value: '0',
  v: '0xfe7',
  r:
   '0xd5f619d21fd65a2e1c4932d7e05ceb1915e1ef372178516540cc18e826c1948e',
  s:
   '0x339897088d253d153384f117a8c14caae105588494d698e1e17199cb8569d805',
  blockNumber: undefined,
  transactionIndex: undefined }

The info I need is the address created for the deployed smart contract. How can I get it from the following output? (in my case the contract address was: 0x720ecB9f06F5563b70Acf6EAB8CfB2e03cE4670E from etherum-lite-exploere)
Any idea in how to get the same result using web3? Thanks in advance.

[cgewecke]

Hi @yehia67

web3.eth.getTransactionReceipt fetches the receipt for a transaction hash. The receipt has a contactAddress field filled in if the tx was a deployment.

Closing because addressed by existing documentation.

[yehia67]

@cgewecke I tried to use it but it return null.

[yehia67]

@cgewecke I tried to use it but it return null.

[cgewecke]

@yehia67

Are you waiting until after the transaction is mined to fetch the receipt?

[yehia67]

I use await
const transaction = await web3.eth.getTransactionReceipt(sendSignedTransaction.result);

[yehia67]

It works!
when I used setTimout to wait for 3 seconds then used getTransactionReceipt.

Is it possible to use event?

I use hyperledger BESU. They don't accept sendTransaction so I had to make an API call to the blockchain const sendSignedTransaction = await curlCall.execute(request,URL); is there any way better way than making a delay to wait till the transaction is mined?

[cgewecke]

@yehia67 web3.eth.sendSignedTransaction resolves the receipt when the tx is mined. There are usage examples in the integration tests, here.

[yehia67]

It works!
Thank you very much😁