I'm currently using ERC721PresetMinterPauserAutoId for a smart contract and the Web3.js library in the Node.js backend server. When I try to call the mint function using this Web3 API:
var myContract = new web3.eth.Contract(ERC721PresetMinterPauserAutoIdABI, ERC721PresetMinterPauserAutoIdContractAddress, {
from: from,
gasPrice: gasPrice
});
let result;
try {
result = await myContract.methods.mint(receipientAddress).send();
res.status(201).send(result)
} catch (error) {
res.status(201).send(error)
}
I get the following error:
Returned error: The method eth_sendTransaction does not exist/is not available
I'm communicating to the Rinkeby blockchain through the Infura gateway and according to this post, Infura supports only eth_sendRawTransaction, not eth_sendTransaction.
I was able to successfully send Ether using a signed transaction:
const gasPrice = await web3.eth.getGasPrice()
const txCount = await web3.eth.getTransactionCount(from, 'pending')
var rawTx = {
nonce: txCount,
gasPrice:"0x" + gasPrice,
gasLimit: '0x200000',
to: to,
value: "0x1000000000000000",
data: "0x",
chainId: 4
};
var privateKey = new Buffer.from(pk, "hex")
var tx = new Tx(rawTx, {"chain": "rinkeby"});
tx.sign(privateKey);
var serializedTx = tx.serialize();
const signedTx = await web3.eth.sendSignedTransaction("0x" + serializedTx.toString("hex"));
However, I'm unable to call the mint method on the smart contract using the raw transaction. I've tried:
await myContract.methods.mint(receipientAddress).sendSignedTransaction("0x" + serializedTx.toString("hex"));
or
await myContract.methods.mint(receipientAddress).sendRawTransaction("0x" + serializedTx.toString("hex"));
But, I still get the error message eth_sendTransaction does not exist/is not available.
Update
I tried using signing the transaction using a Truffle's library on the advise of #MikkoOhtamaa:
const HDWalletProvider = require("#truffle/hdwallet-provider");
const privateKeys = process.env.PRIVATE_KEYS || ""
const walletAPIUrl = `https://rinkeby.infura.io/v3/${process.env.INFURA_API_KEY}`
const provider = new HDWalletProvider(
privateKeys.split(','),
walletAPIUrl
);
const web3 = new Web3API(provider)
Install a Web3.js middleware layer that signs transactions locally, instead of sending a JSON-RPC method to Infura.
One of the solutions is Truffle HDWallet.
Related
I am trying to sign a message with wallet connect using ethers, but I am facing an issue when verifying the message with ambire wallet, it's not returning any response.
const signMessage = async () => {
try {
console.log("started");
// 1.] create a provider
const walletConnectProvider = new WalletConnectProvider({
infuraId: "3cd774e14cf34ff78167908f8377051c", // Required
// qrcode: true
});
// 2.] enable provider
await walletConnectProvider.enable();
// console.log(walletConnectProvider.wc.accounts[0]);
let rawMessage = "Hello World";
let rawMessageLength = new Blob([rawMessage]).size;
let message = ethers.utils.toUtf8Bytes(
"\x19Ethereum Signed Message:\n" + rawMessageLength + rawMessage
);
message = ethers.utils.keccak256(message);
var params = [
walletConnectProvider.wc.accounts[0],
message,
];
// 3.] sign message
const provider = new providers.Web3Provider(walletConnectProvider);
const signer = provider.getSigner();
let signature = await signer.signMessage(message);
console.log("signature", signature);
// 4.] verify message
let verified = await ethers.utils.verifyMessage(message, signature);
console.log("verified", verified);
} catch (err) {}
};
there are a couple of things you additionally need:
You need to pass the original message (before prefix) to signer.signMessage, in other words the rawMessage: await signer.signMessage(rawMessage) - because the wallet (no matter if it's Ambire or not) will add the prefix
In order to support smart wallets like Ambire, Gnosis Safe, Argent and others, you need to implement EIP 1271.
In JS (warning: not tested), this will look somewhat like this:
const signerAddr = await signer.getAddress();
if (provider.getCode(signerAddr) === '0x') {
// Regular RSV sig verification
verified = signerAddr === (await ethers.utils.verifyMessage(message, signature));
} else {
// Smart contract wallet (EIP 1271) verification: see https://eips.ethereum.org/EIPS/eip-1271 for more info
const EIP1271ABI = ['function isValidSignature(bytes32 _hash, bytes memory _signature) public view returns (bytes4 magicValue)'];
const EIP1271MagicValue = '0x1626ba7e';
const signerEIP1271Contract = new ethers.Contract(signerAddr, EIP1271ABI, provider);
const rawMessageLength = new Blob([rawMessage]).size;
const message = ethers.utils.toUtf8Bytes(
"\x19Ethereum Signed Message:\n" + rawMessageLength + rawMessage
);
const messageHash = ethers.utils.keccak256(message);
verified = EIP1271MagicValue === (await signerEIP1271Contract.isValidSignature(messageHash, signature));
}
NOTE: We, the Ambire team, are currently working on a comprehensive guide on how to verify all styles of signature (EIP1271, EIP712, 712+1271, regular), which will hopefully be linked by the ethers.js documentation.
EDIT: We've published a library that makes this a whole lot easier, please check it out: https://github.com/AmbireTech/signature-validator/ - we recommend that you use that
I have an NFT Contract and I need to mint NFTs. Also I have a second contract
for handling buying and selling NFTs into this contract.
I am using the ethers library.
this is my code for config:
static async Initial(): Promise<any> {
let provider = new ethers.providers.JsonRpcProvider(config.contractConfig.url);
const signer = provider.getSigner();
this.tokenContract = new ethers.Contract(config.contractConfig.nftAddress, NFT.abi, provider);
this.dNFT = new ethers.Contract(config.contractConfig.dortajNftAddress, DNFT.abi, signer);
}
config address:
export default {
nftAddress: '0x444F15B115ED9663DAE46786a34AA3F6E8c0B57D',
dortajNftAddress: '0x8e4bE2a3BD1169596c38952D8e837b20D419Bcd1',
url : 'HTTP://127.0.0.1:7545'
}
now i need to use this function for mint nft :
let transaction = await this.tokenContract.mintToken();
const tx = await transaction.wait();
but it show me this error:
Error: sending a transaction requires a signer (operation="sendTransaction", code=UNSUPPORTED_OPERATION, version=contracts/5.5.0)
How can I solve this problem?
In this line
this.tokenContract = new ethers.Contract(config.contractConfig.nftAddress, NFT.abi, provider);
try to pass signer instead of provider.
How can I interact with smart contracts and send transactions with Web3.js by having a local private key? The private key is either hardcoded or comes from an environment (.env) file?
This is needed for Node.js and server-side interaction or batch jobs with Ethereum/Polygon/Binance Smart Chain smart contracts.
You may encounter e.g. the error
Error: The method eth_sendTransaction does not exist/is not available
Ethereum node providers like Infura, QuikNode and others require you to sign outgoing transactions locally before you broadcast them through their node.
Web3.js does not have this function built-in. You need to use #truffle/hdwallet-provider package as a middleware for your Ethereum provider.
Example in TypeScript:
const Web3 = require('web3');
const HDWalletProvider = require("#truffle/hdwallet-provider");
import { abi } from "../../build/contracts/AnythingTruffleCompiled.json";
//
// Project secrets are hardcoded here
// - do not do this in real life
//
// No 0x prefix
const myPrivateKeyHex = "123123123";
const infuraProjectId = "123123123";
const provider = new Web3.providers.HttpProvider(`https://mainnet.infura.io/v3/${infuraProjectId}`);
// Create web3.js middleware that signs transactions locally
const localKeyProvider = new HDWalletProvider({
privateKeys: [myPrivateKeyHex],
providerOrUrl: provider,
});
const web3 = new Web3(localKeyProvider);
const myAccount = web3.eth.accounts.privateKeyToAccount(myPrivateKeyHex);
// Interact with existing, already deployed, smart contract on Ethereum mainnet
const address = '0x123123123123123123';
const myContract = new web3.eth.Contract(abi as any, address);
// Some example calls how to read data from the smart contract
const currentDuration = await myContract.methods.stakingTime().call();
const currentAmount = await myContract.methods.stakingAmount().call();
console.log('Transaction signer account is', myAccount.address, ', smart contract is', address);
console.log('Starting transaction now');
// Approve this balance to be used for the token swap
const receipt = await myContract.methods.myMethod(1, 2).send({ from: myAccount.address });
console.log('TX receipt', receipt);
You need to also avoid to commit your private key to any Github repository. A dotenv package is a low entry solution for secrets management.
You can achieve what you want by using ethers.js instead of web3 with no other package needed.
First import the library:
Node.js:
npm install --save ethers
const { ethers } = require("ethers");
Web browser:
<script src="https://cdn.ethers.io/lib/ethers-5.2.umd.min.js"
type="application/javascript"></script>
Define the provider. One way is using the provider URL like this:
const provider = new ethers.providers.JsonRpcProvider(rpcProvider);
Then, in order to interact with the contract without asking for authorization, we will create a wallet using the private key and the provider like this:
const signer = new ethers.Wallet(privateKey,provider)
Now, you can create the contract with the address, ABI, and the signer we created in the previous step:
const contract = new ethers.Contract(contractAddress,ABI, signer);
Now, you can interact with the contract directly. For example, getting the balance of a token:
const tokenBalance = await nftContractReadonly.balanceOf(signer.getAddress(),tokenId);
Don't forget to store the private key in a safe place and never hardcode it in a web page.
Further reading: Provider Signer
There is a better and simple way to sign and execute the smart contract function. Here your function is addBonus.
First of all we'll create the smart contract instance:
const createInstance = () => {
const bscProvider = new Web3(
new Web3.providers.HttpProvider(config.get('bscRpcURL')),
);
const web3BSC = new Web3(bscProvider);
const transactionContractInstance = new web3BSC.eth.Contract(
transactionSmartContractABI,
transactionSmartContractAddress,
);
return { web3BSC, transactionContractInstance };
};
Now we'll create a new function to sign and execute out addBonus Function
const updateSmartContract = async (//parameters you need) => {
try {
const contractInstance = createInstance();
// need to calculate gas fees for the addBonus
const gasFees =
await contractInstance.transactionContractInstance.methods
.addBonus(
// all the parameters
)
.estimateGas({ from: publicAddress_of_your_desired_wallet });
const tx = {
// this is the address responsible for this transaction
from: chainpalsPlatformAddress,
// target address, this could be a smart contract address
to: transactionSmartContractAddress,
// gas fees for the transaction
gas: gasFees,
// this encodes the ABI of the method and the arguments
data: await contractInstance.transactionContractInstance.methods
.addBonus(
// all the parameters
)
.encodeABI(),
};
// sign the transaction with a private key. It'll return messageHash, v, r, s, rawTransaction, transactionHash
const signPromise =
await contractInstance.web3BSC.eth.accounts.signTransaction(
tx,
config.get('WALLET_PRIVATE_KEY'),
);
// the rawTransaction here is already serialized so you don't need to serialize it again
// Send the signed txn
const sendTxn =
await contractInstance.web3BSC.eth.sendSignedTransaction(
signPromise.rawTransaction,
);
return Promise.resolve(sendTxn);
} catch(error) {
throw error;
}
}
I need to call methods from my contract in Ethereum without using MetaMask. I use Infura API and try to call my methods from account, recently created with web3.eth.create() method. This method returns object like this:
{
address: "0xb8CE9ab6943e0eCED004cG5834Hfn7d",
privateKey: "0x348ce564d427a3311b6536bbcff9390d69395b06ed6",
signTransaction: function(tx){...},
sign: function(data){...},
encrypt: function(password){...}
}
I also using infura provider:
const web3 = new Web3(new Web3.providers.HttpProvider(
"https://rinkeby.infura.io/5555666777888"
))
So, when I try to write smth like that:
contract.methods.contribute().send({
from: '0xb8CE9ab6943e0eCED004cG5834Hfn7d', // here I paste recently created address
value: web3.utils.toWei("0.5", "ether")
});
I have this error:
Error: No "from" address specified in neither the given options, nor
the default options.
How it could be no from address if I write it in from option??
P.S. With Metamask my application works fine. But when I logout from MetaMask and try to create new account and use it, I have that issue.
In fact, we can't just send transactions from newly created address. We must sign this transaction with our private key. For example, we can use ethereumjs-tx module for NodeJS.
const Web3 = require('web3')
const Tx = require('ethereumjs-tx')
let web3 = new Web3(
new Web3.providers.HttpProvider(
"https://ropsten.infura.io/---your api key-----"
)
)
const account = '0x46fC1600b1869b3b4F9097185...'; //Your account address
const privateKey = Buffer.from('6e4702be2aa6b2c96ca22df40a004c2c944...', 'hex');
const contractAddress = '0x2b622616e3f338266a4becb32...'; // Deployed manually
const abi = [Your ABI from contract]
const contract = new web3.eth.Contract(abi, contractAddress, {
from: account,
gasLimit: 3000000,
});
const contractFunction = contract.methods.createCampaign(0.1); // Here you can call your contract functions
const functionAbi = contractFunction.encodeABI();
let estimatedGas;
let nonce;
console.log("Getting gas estimate");
contractFunction.estimateGas({from: account}).then((gasAmount) => {
estimatedGas = gasAmount.toString(16);
console.log("Estimated gas: " + estimatedGas);
web3.eth.getTransactionCount(account).then(_nonce => {
nonce = _nonce.toString(16);
console.log("Nonce: " + nonce);
const txParams = {
gasPrice: 100000,
gasLimit: 3000000,
to: contractAddress,
data: functionAbi,
from: account,
nonce: '0x' + nonce
};
const tx = new Tx(txParams);
tx.sign(privateKey); // Transaction Signing here
const serializedTx = tx.serialize();
web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex')).on('receipt', receipt => {
console.log(receipt);
})
});
});
Transaction time is about 20-30 seconds so you should wait quite a bit.
It's easy to use web3js to call functions that don't require signing (e.g. functions that do not update the state of a contract). However, it's not clear how to call functions that require signing, other than manually unlocking my MetaMask wallet and calling functions inside Remix environment.
After deploying my dapp for the first time to Ropsten, I need to call createItem(string name, uint price) 100 times to populate the items array initially. Since I don't want to do it manually in Remix, I want to write a script that does it automatically.
It looks like I need to have ethereumjs-tx in addition to web3js to sign transactions programatically without having MetaMask. I also need to have my account and privateKey. With all this information and the official web3js doc, I come up with the following:
// Call an external function programatically
const web3 = new Web3(new Web3.providers.HttpProvider("https://ropsten.infura.io"))
const account = "ACCOUNT_ADDRESS"
const privateKey = new Buffer('PRIVATE_KEY', 'hex')
const contract = new web3.eth.Contract(abi, CONTRACT_ADDRESS, {
from: account,
gas: 3000000,
})
const functionAbi = contract.methods.myFunctionName(myArgument).encodeABI()
let estimatedGas
contract.methods.myFunctionNAme(myArgument).estimateGas({
from: account,
}).then((gasAmount) => {
estimatedGas = gasAmount.toString(16)
})
const txParams = {
gasPrice: '0x' + estimatedGas,
to: CONTRACT_ADDRESS,
data: functionAbi,
from: account,
}
const tx = new Tx(txParams)
tx.sign(privateKey)
const serializedTx = tx.serialize()
web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex')).
on('receipt', console.log)
The code runs, but txParams is actually missing one key: nonce. When you run this, you get the following error:
Unhandled rejection Error: Returned error: nonce too low
Here are my questions:
Is this generally the right way to do what I am trying to do?
If 1 is true, how do I get the nonce parameter for a deployed contract?
References:
http://web3js.readthedocs.io/en/1.0/
https://github.com/ethereumjs/ethereumjs-tx
https://ethereum.stackexchange.com/questions/21402/web3-eth-call-how-can-i-set-data-param
https://ethereum.stackexchange.com/questions/6368/using-web3-to-sign-a-transaction-without-connecting-to-geth
UPDATE:
Thanks to Adam, now I learned how to get the nonce. So I added this following code:
let nonce
web3.eth.getTransactionCount(account).then(_nonce => {
nonce = _nonce.toString(16)
})
const txParams = {
gasPrice: '0x' + gasPrice,
to: CONTRACT_ADDRESS,
data: functionAbi,
from: account,
nonce: '0x' + nonce,
}
But now I keep running into this exception:
Unhandled rejection Error: Returned error: rlp: input string too long
for uint64, decoding into
(types.Transaction)(types.txdata).AccountNonce
Google search wasn't helpful except for letting me locate this file (https://github.com/ethereum/go-ethereum/blob/master/rlp/decode.go) that has the exception handler. Does anyone know how to solve this?
Generally looks correct. The only question I would have is how are you planning on loading the private key? You will either need to prompt for the private key, or import/read in the keystore and prompt for the password. You can use keythereum to accomplish this (See the key import section for example code).
The nonce is just an incremental number used to order transactions for an account. To get the correct value, simply use web3.eth.getTransactionCount(account)
EDIT - Example run using Ganache with locked accounts (--secure option):
SimpleContract.sol
pragma solidity ^0.4.19;
contract SimpleContract {
uint public val = 4;
function increment(uint amt) public {
val += amt;
}
function get() public constant returns (uint) {
return val;
}
}
test.js
const Web3 = require('web3');
const Tx = require('ethereumjs-tx');
const provider = new Web3.providers.HttpProvider("http://localhost:8545");
const web3 = new Web3(provider);
const account = '0x9a6d82ef3912d5ab60473124bccd2f2a640769d7'; // Ganache
const privateKey = Buffer.from('70f1384b24df3d2cdaca7974552ec28f055812ca5e4da7a0ccd0ac0f8a4a9b00', 'hex');
const contractAddress = '0x6dd7c1c13df7594c27e0d191fd8cc21efbfc98b4'; // Deployed manually
const abi = [{"constant":true,"inputs":[],"name":"val","outputs":[{"name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"get","outputs":[{"name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"amt","type":"uint256"}],"name":"increment","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"}];
const contract = new web3.eth.Contract(abi, contractAddress, {
from: account,
gasLimit: 3000000,
});
const contractFunction = contract.methods.increment(3);
const functionAbi = contractFunction.encodeABI();
let estimatedGas;
let nonce;
console.log("Getting gas estimate");
contractFunction.estimateGas({from: account}).then((gasAmount) => {
estimatedGas = gasAmount.toString(16);
console.log("Estimated gas: " + estimatedGas);
web3.eth.getTransactionCount(account).then(_nonce => {
nonce = _nonce.toString(16);
console.log("Nonce: " + nonce);
const txParams = {
gasPrice: '0x09184e72a000',
gasLimit: 3000000,
to: contractAddress,
data: functionAbi,
from: account,
nonce: '0x' + nonce
};
const tx = new Tx(txParams);
tx.sign(privateKey);
const serializedTx = tx.serialize();
contract.methods.get().call().then(v => console.log("Value before increment: " + v));
web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex')).on('receipt', receipt => {
console.log(receipt);
contract.methods.get().call().then(v => console.log("Value after increment: " + v));
})
});
});
Results:
$ npm run my_test
> hello_world_dapp#1.0.0 my_test C:\cygwin\home\adamk\eth\hello_world_dapp
> node ./test.js
Getting gas estimate
Estimated gas: 6919
Nonce: 5
Value before increment: 19
{ transactionHash: '0xb6fdfc36cc32cb01a2be8832a387da586a44a37c1241bbf2979745536f206ed4',
transactionIndex: 0,
blockHash: '0xb6ee8d4e45585010d9a12d48aa37a478eb6021aad78599f1719cb424ab364bb5',
blockNumber: 10,
gasUsed: 26905,
cumulativeGasUsed: 26905,
contractAddress: null,
logs: [],
status: 1 }
Value after increment: 22
Here is a code-snippet for sending signed transaction on rinkeby.In a similar way,you can proceed for ropsten test network:
const Tx = require('ethereumjs-tx')
const Web3 = require('web3')
const web3 =new
Web3('https://rinkeby.infura.io/v3/9ce80a86c6c54d22aa821d0486a1a47d')
var account1 = '0xa00c70B72150D627cf53872eefD077079116B6a6'
var account2 = '0xD2a8aa318Fbc56995Db8C415BE6E40329DB1C56C'
const privateKey1 = Buffer.from(process.env.PRIVATE_KEY_1,'hex')
const privateKey2 = Buffer.from(process.env.PRIVATE_KEY_2,'hex')
web3.eth.getTransactionCount(account1,(err,txCount)=>{
const txObject = {
nonce:web3.utils.toHex(txCount),
to:account2,
value:web3.utils.toHex(web3.utils.toWei('0.1','ether')),
gasLimit:web3.utils.toHex(21000),
gasPrice:web3.utils.toHex(web3.utils.toWei('10','gwei')),
}
console.log(txObject)
const tx = new Tx(txObject)
tx.sign(privateKey1)
const serializedTransaction = tx.serialize()
const raw = '0x'+serializedTransaction.toString('hex')
web3.eth.sendSignedTransaction(raw,(err,txHash)=>{
console.log(txHash)
})
})