How to get reason revert using web3.eth.call

Question

I have a smart contract with required message and pretend to use the required/validation message in front end.

require(bytes(hashAlreadyRegistered[hash]).length  == 0, "Hash already registered");

I'm trying to get the reason of revert using web3.eth.call.

By my understanding reading the doc if i pass the object generated by sendTransaction it will work. I think it is what i'm trying to do but didn't work so far.

My codes

sendTransaction method:

await canManipuleContract.methods.setDocumentHash('#_' + request.body.hash)
    .send({
      from: fromAddress,
      gas: 400000,
      gasPrice: 21000000000
    })
    .then(function(txRaw) {
      console.log(txRaw)
      return response.json( txRaw.transactionHash );
    })
    .catch(function(error) {
      handleRevert(error);
      console.log("Error: \n" + error);
      return response.json( 'error' )
    })
  }

web3.eth.call method:

function handleRevert( transactionObject ) {
    web3.eth.call( transactionObject, function( err, result ) {
      if ( ! err ) {
        console.log( 'result ' + result )
      }
      console.log( 'err ' +  err)
      //return response.json( 'Error: Returned error: execution reverted' )
    })
  }

The return value of handleRevert is always err 0x. In geth console i clearly see the value err and errdata returning the correct messages.

If i pass the contract address instead transactionObject in web3.eth.call method it always return Error: Returned error: execution reverted, but never the required message it self.

Version:

Geth: 1.9.15-stable

web3.js: ^1.2.8

What am i missing here? Any others methods to get the message required of smart contract will help here.

Answer 1

Try this,

async function getRevertReason(txHash){

  const tx = await web3.eth.getTransaction(txHash)

  var result = await web3.eth.call(tx, tx.blockNumber)

  result = result.startsWith('0x') ? result : `0x${result}`

  if (result && result.substr(138)) {

    const reason = web3.utils.toAscii(result.substr(138))
    console.log('Revert reason:', reason)
    return reason

  } else {

    console.log('Cannot get reason - No return value')

  }

}

Answer 2

Web3 supports revert strings now: https://web3js.readthedocs.io/en/v1.2.8/web3-eth.html#handlerevert.

You can activate it easily by setting web3.eth.handleRevert = true. Now when you use call or send functions, precisely one of the following:

• web3.eth.call()
• web3.eth.sendTransaction()
• contract.methods.myMethod(…).send(…)
• contract.methods.myMethod(…).call(…)

you will see a new message like

Error: Your request got reverted with the following reason string: This is the revert reason!

Answer 3

There is a handleRevert property in web3 itself. For me, it only works when I set web3.handleRevert = true instead of the documented option, web3.eth.handleRevert = true. The error message comes back in the reason attribute of the Error object that is thrown by the send() call of a smart contract method.

Answer 4

Follow this. Basically different RPC's will have different error response data. So you'll have to check the response and then simply use parseError on contract's interface.

https://ethereum.stackexchange.com/a/142364/128523