JSON RPC Signer fails on erc20_contract.transfer

[SleepingProgrammer]

I'm using a JSON RPC Signer to do contract calls to my erc20 token contract.

It works fine locally but when I tested it on rinkeby it fails with an:

index.js:202 Uncaught (in promise) Error: processing response error (body="{"jsonrpc":"2.0","id":47,"error":{"code":-32601,"message":"The method eth_sendTransaction does not exist/is not available"}}", error={"code":-32601}, requestBody="{"method":"eth_sendTransaction","params":[{"gas":"0x8a0d","from":"0xd5429b90c893be82cdb25678067286d65fad1412","to":"0x2f3141791367181b206fa53c6e4b5b419c7176a5","data":"0xa9059cbb00000000000000000000000048635bed4ec31edd06b0ed6074f47a546d3e543a0000000000000000000000000000000000000000000000000000000000000015"}],"id":47,"jsonrpc":"2.0"}", requestMethod="POST", url="https://rinkeby.infura.io/v3/{just my project id}", code=SERVER_ERROR, version=web/5.3.0)

Here's the code that I used.

`
const jsonRpcProvider = new ethers.providers.JsonRpcProvider(jsonRpcProviderURI);
var jsonRpcSigner = jsonRpcProvider.getSigner(signerAddress);

const signedContract = await TokenContract.connect(jsonRpcSigner);
console.log("autoSignedTransfer/signedContract", signedContract);
const transferResult = await signedContract.transfer(accounts[0], token_amount);
console.log("transferResult", transferResult);

`

[zemse]

You can only do the following if you are using a node that contains your private key. Supported backends could be using geth/parity containing accounts as well as exposed over RPC API, metamask or ganache / hardhat network.

const jsonRpcProvider = new ethers.providers.JsonRpcProvider(jsonRpcProviderURI);
var jsonRpcSigner = jsonRpcProvider.getSigner(signerAddress);

But from your error it appears that you're using infura. And infura doesn't support having remote accounts (private key on the node). So jsonRpcProvider.getSigner(signerAddress) won't immediately error but when you go ahead and use it (when you are doing contract.writeMethod), it would fail.

So do you have private key to signerAddress ? If yes you can use Wallet. If you have it over an hardware wallet, you can checkout LedgerSigner, if you have something else, you need a signer for it.

[SleepingProgrammer]

Hi @zemse thank you very much for the response.

Yes, I'm having a problem with making requests to the infura provider.

What I currently use is this.

`
//Contract, provider and signer setup
const Token = await ethers.getContractFactory("Token");
var token = await Token.attach(this.contractAddress);
const provider = new ethers.providers.JsonRpcProvider(process.env.JSON_RPC_PROVIDER_URI);
const wallet = new ethers.Wallet(process.env.ATM_PRIVATE_KEY, provider);
const signer = provider.getSigner(process.env.ATM_ADDRESS);
token = token.connect(signer);

//async Transfer call
var unsignedTransaction = await token.populateTransaction.transfer(address, value);
var signedTransaction = await wallet.signTransaction(unsignedTransaction);
var transferReceipt = await this.infuraProvider.sendTransaction(signedTransaction);
`

I honestly don't know if what I'm doing is right so please let me know if you have some suggestions for an improvement or if I'm doing this completely wrong. I'm fairly new so any additional info would be valuable. Thanks!

[zemse]

You can remove the const signer as it is not used. Then you can simply call the method instead of the 3 lines.

const wallet = new ethers.Wallet(process.env.ATM_PRIVATE_KEY, provider);
token = token.connect(wallet);

//async Transfer call
const tx = await token.transfer(address, value);

[SleepingProgrammer]

Okay, thanks @zemse! I found out that it wasn't working earlier as I didn't add the new contract address on infura to the allowed ethereum addresses. It works properly now, thanks for the help stay awesome!