[SDK] Unable to use Paymaster on ZkSync Sepolia Testnet using zksync-ethers (Javascript V6)

[ken-cronos]

Environment

Testnet

Acknowledgement

• I understand that issues are expected with the Go SDK as they are being updated.

Issue Description

Building a NextJS front end similar to the "hello world" front end project of the documentation.
What's changed is that I am using zksync-ethers (Ethers V6 instead of V5 and Sepolia as the testnet (instead of Goerli).
When using Paymaster to pay for gas fees, I am facing an error. The code works when paying gas in ETH, but does not work when using a custom ERC20 token deployed to zkSync Sepolia Testnet to pay for gas. Any suggestion welcome.

Error in browser's javascript console:

errors.js:122 Uncaught (in promise) TypeError: unsupported addressable value (argument="target", value=null, code=INVALID_ARGUMENT, version=6.9.1)
    at makeError (errors.js:122:21)
    at assert (errors.js:149:15)
    at assertArgument (errors.js:161:5)
    at Object.resolveAddress (checks.js:117:35)
    at Signer.sendTransaction (signer.js:97:48)
    at async handleSubmitMessageButton (page.tsx:269:33)

Expected Behavior

Transaction should complete with custom token to pay for gas. (The code works when paying gas in ETH.)

Code Example

import {
    BrowserProvider as ZkSyncBrowserProvider,
    Contract as zkSyncContract,
    Provider as ZkSyncProvider,
    utils as ZkSyncUtils
} from "zksync-ethers";
import {ethers} from "ethers";
...

const handleSubmitMessageButton = async (message: string | null) => {  
    if (message) {  
        const serverZkStackProvider = new ZkSyncProvider(process.env.NEXT_PUBLIC_BLOCKCHAIN_URL);  
        const userZkStackProvider = new ZkSyncBrowserProvider(window.ethereum);  
        const userZkStackSigner = await userZkStackProvider.getSigner();  
        const greeterContract = new zkSyncContract(  
            process.env.NEXT_PUBLIC_GREETER_CONTRACT_ADDRESS ? process.env.NEXT_PUBLIC_GREETER_CONTRACT_ADDRESS : "",  
            greeterContractJson.abi,  
            userZkStackSigner  
        )  
        // Configure overrides  
        let overrides = {}  
        if (selectedToken.name != "Ether") {  
            console.log("Trying to send transaction via paymaster...")  
            const testnetPaymaster =  
                await serverZkStackProvider.getTestnetPaymasterAddress();  
            if (testnetPaymaster) {  
                const gasPrice = await userZkStackProvider.getGasPrice();  
                // estimate gasLimit via paymaster  
                const initialPaymasterInput = {  
                    type: "ApprovalBased",  
                    minimalAllowance: BigInt(1),  
                    token: selectedToken.address,  
                    innerInput: new Uint8Array(),  
                }  
                const paramsForFeeEstimation = ZkSyncUtils.getPaymasterParams(  
                    testnetPaymaster,  
                    {  
                        type: "ApprovalBased",  
                        minimalAllowance: BigInt(1),  
                        token: selectedToken.address,  
                        innerInput: new Uint8Array(),  
                    }  
                );  
                // estimate gasLimit via paymaster  
                const gasLimit = await greeterContract.setGreeting.estimateGas({  
                    message,  
                    customData: {  
                        gasPerPubdata: ZkSyncUtils.DEFAULT_GAS_PER_PUBDATA_LIMIT,  
                        paymasterParams: paramsForFeeEstimation,  
                    },  
                })  
                const fee = gasPrice * BigInt(gasLimit.toString());  
                const newPaymasterInput = {  
                    type: "ApprovalBased",  
                    token: selectedToken.address,  
                    minimalAllowance: fee,  
                    // empty bytes as testnet paymaster does not use innerInput  
                    innerInput: new Uint8Array(),  
                }  
                const paymasterParams = ZkSyncUtils.getPaymasterParams(testnetPaymaster, {  
                    type: "ApprovalBased",  
                    token: selectedToken.address,  
                    minimalAllowance: fee,  
                    // empty bytes as testnet paymaster does not use innerInput  
                    innerInput: new Uint8Array(),  
                });  
                overrides = {  
                    maxFeePerGas: gasPrice,  
                    maxPriorityFeePerGas: BigInt(0),  
                    gasLimit: gasLimit,  
                    customData: {  
                        gasPerPubdata: ZkSyncUtils.DEFAULT_GAS_PER_PUBDATA_LIMIT,  
                        paymasterParams,  
                    },  
                };  
            }  
        }  
        // Execute transaction  
        const txPayload = await greeterContract.setGreeting.populateTransaction(message);
        const transaction = await userZkStackSigner.sendTransaction({...txPayload, ...overrides});  
    }  
}

Repo Link (Optional)

No response

[MexicanAce]

Hey @ken-cronos 👋 !

We're able to get a local version of zksync-ethers (Ethers V6) working with a paymaster in our Sepolia Testnet See example here. Could you share more information about your ZK Stack setup? Perhaps there's something else going on that would help provide more information.

[MexicanAce]

instead of Goerli

Do you know if the same contracts/scripts were successful in deployment for Goerli Testnet?

[hinataa01]

test

[ken-cronos]

thank you, solved