How to recoverPubKey from signature and raw message?

[benben2019]

The following code is a function for recovering the public key in the web3.swift library (https://github.com/Boilertalk/Web3.swift). It recovers the public key only from the signature and the original message data. How can I achieve this in the wallet-core library? Thank you!

    public func recoverPubKey(signature: EthereumSignature, message: Data) throws -> Data {
        let publicKey = try EthereumPublicKey(
            message: message.bytes,
            v: EthereumQuantity(quantity: BigUInt(signature.v)),
            r: EthereumQuantity(signature.r),
            s: EthereumQuantity(signature.s)
        )
        return Data(publicKey.rawPublicKey)
    }

[benben2019]

this may be working!

  public func recoverPubKey(signature: EthereumSignature, message: Data) throws -> Data {
        let hashBytes = SHA3(variant: .keccak256).calculate(for: message.bytes)
        let hashData = Data(hashBytes)
        guard let publicKey = SECP256K1.recoverPublicKey(hash: hashData, signature: signature.serialized, compressed: true) else {
            throw "recover publickKey error"
        }
        return publicKey
    }

[satoshiotomakan]

If you want to achieve the same with WalletCore, please consider using this code:

let msgHash = Hash.Keccak256(message)

var rawSig = Bytes()
let r = signature.r.quantity.makeBytes().trimLeadingZeros()
let s = signature.s.quantity.makeBytes().trimLeadingZeros()
rawSig.append(contentsOf: r)
rawSig.append(contentsOf: s)

let publicKey = PublicKey.recover(rawSig, msgHash)

Please let me know if it works for you (I haven't tested)