Transactions – How to Check If Transaction Is Interacting with Smart Contract or Deploying It

deployed-bytecodetransactions

I'm currently working with go-ethereum,

And unable to use etherscan for this case,

No ABI for me here.

How to check whether if the transaction interacts with/calls a smart contract or deploying the smart contract itself?

And if it deploys the smart contract how can I know the smart contract address deployed?

Best Answer

Well what you can do is in the geth console you can use the web3.eth.getTransactionReceipt(<TX_HASH>) method to get the transaction receipt. Let's take Chainlink contract creation transaction for example:

As you can see the to value is null and the contractAddress value is the value of Chainlink contract. So whenever we have empty to value and contractAddress is not empty then we're speaking of contract creation.

Contract method requests can be caught with the transaction hash by using method web3.eth.getTransaction(<TX_HASH>). In the response of this method if the to value is the contract address and data value is not empty ( it has to be valid encoded ABI of the particular method ) then we're definitely speaking for contract method request.

Related Solutions

Web3.py – How Can the Transaction Hash / Block Hash of an Already Deployed Contract Be Retrieved?

Since you're interested in arbitrary contracts that don't emit events, you'll have to scan each block. Additionally, to capture scenarios where the contract you're interested in is called by another contract (instead of an Externally Owned Account), you'll likely have to run a trace on each transaction.

Traces are non-standard (client-specific) mechanisms for peeking inside the EVM mechanics of a transaction. Infura does not support traces, AFAIK. So you'll almost certainly have to run a local node.

Web3.py only supports parity traces, currently, so I'd probably start there. Unfortunately they're not documented in web3.py docs at the moment. You would roughly do something like:

from web3.auto import w3
from web3.parity import Parity
Parity.attach(w3, 'parity)
trace_results = w3.parity.traceReplayBlockTransactions('latest')

You can find more parity trace methods in the web3py source.

Transactions – How to Calculate Gas Fees for Deploying a Smart Contract Using Hardhat

Use effectiveGasPrice value directly from the receipt, instead of ethers.provider.getGasPrice

const transactionReceipt = await ethers.provider.getTransactionReceipt(receipt.transactionHash);
const gasUsed = transactionReceipt.gasUsed;
const gasPricePaid = transactionReceipt.effectiveGasPrice;
const transactionFee = gasUsed.mul(gasPricePaid);

`provider.getGasPrice 🔗`

— returns suggested gas price for current/next transactions. You call this before sending the transaction, to estimate the gas price.

Best Answer

Related Solutions

Web3.py – How Can the Transaction Hash / Block Hash of an Already Deployed Contract Be Retrieved?

Transactions – How to Calculate Gas Fees for Deploying a Smart Contract Using Hardhat

provider.getGasPrice 🔗

Related Topic

`provider.getGasPrice 🔗`