Error Handling with MetaMask Payable Functions
As a developer building decentralized applications (dApps) on the Ethereum blockchain, you are probably familiar with the importance of handling errors and exceptions when interacting with smart contracts. In this article, we will look at how to resolve an error that occurs when calling a payable function using the Metamask signature method.
Understanding the Error
The error message you provided indicates an internal JSON-RPC error. This is not unexpected, as MetaMask usually handles errors internally and passes them on to your application code. However, understanding what this error means is essential to resolving the issue.
The error consists of three components:
- “code”: 32603 – A specific Ethereum code that indicates an internal error.
- “message”: Internal JSON-RPC error – An error message that describes the cause of the error.
data: { “code”: 3, “message”: “execution rolled back” } – Details of the actual error.
Troubleshooting Steps
To resolve this issue, break down the steps as follows:
Step 1: Check the Ether Value
When calling a paying function, you must provide the correct amount of Ether (ETH) as input. To ensure that the Ether value is correct, check that it matches the expected price.
const etherValue = 0x01;
const transaction = {
// other properties
data: {
// other data
"gasPrice": 200,000,
"gasLimit": 20000000,
"to": contractAddress,
"value": etherValue,
"nonce": 1,
"signer": await metamaskSigner.sign(transaction, { to: contractAddress }),
},
};
Step 2: Check the error message and code
Check the error message and code to understand what is happening. In this case, it seems that the error message “execution rolled back” is displayed.
// check the error data
const error = transaction.data;
console.log(error); // { code: 3, message: "execution rolled back" }
Step 3: Handling the execution rolled back error
To handle the execution rolled back error, try the following:
- Increase the “nonce” value to prevent the contract from executing multiple times.
- Try calling the function with a larger amount of Ether that has not yet been spent.
- Check if there are any pending transactions on the blockchain that could be causing the problem.
const transaction = {
// other properties
data: {
gas price: 200,000,
gas limit: 20000000,
to address: contractAddress,
value: etherValue + 1000000, // increase the amount of Ether
nonce: 5, // increase the nonce value
signer: await metamaskSigner.sign(transaction, { to: contractAddress }),
},
};
Best practices
To avoid similar errors in the future:
- When calling a function that requires payment, always check that the ETH value is equal to the expected price.
- Carefully review the error message and code to understand what is happening.
- If you are unsure about how to handle a given error or exception, please refer to the official Ethereum documentation or ask the community for help.
If you follow these steps and best practices, you should be able to resolve the “execution rolled back” error when calling the MetaMask payable function.