Verifying a User’s MetaMask Wallet Address
When using the MetaMask API to authenticate users to your application, it is very important to ensure that the wallet address belongs to the user. In this article, we will explore how to do this.
Understanding the MetaMask API
Before diving into the verification process, let’s quickly review the basics of the MetaMask API:
- The Accounts endpoint returns a list of available MetaMask wallets.
- The GetAccount endpoint retrieves specific wallet information based on the address.
- The Login endpoint authenticates users and returns a username.
Verifying Wallet Address Ownership
To verify that a user’s wallet address belongs to them, you need to retrieve their account information using the getAccount endpoint. Once you have the account information, compare it to the expected address in your application’s database or storage system.
Here is an example of retrieving an account based on its address:
const accountData = await accounts.getAccount(address);
Example implementation
async function authenticateUser() {
const address = '0x1234567890abcdef'; // Replace with the user's wallet address
try {
const response = await fetch('/api/login', {
method: 'POST',
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify({
'address': address,
'secretKey': 'your_secret_key_here' // Replace with your secret key
})
});
const data = await response.json();
if (data.error) {
throw new Error(data.error);
}
const accountData = await accounts.getAccount(address);
console.log(Account information for address ${address}:);
console.log(accountData);
} catch (error) {
console.error(error);
}
}
In this example, we make a POST request to the /api/login endpoint using the user’s wallet address and secret key. The response contains an “accountData” object that contains the account information.
Wallet Address Ownership Comparison
To verify that the wallet address belongs to the user, compare it to your application’s database or storage system. You can do this by retrieving the account information and checking if the given address matches the expected address.
Here is an example implementation:
async function authenticateUser() {
const address = '0x1234567890abcdef'; // Replace with user wallet address
try {
const response = await fetch('/api/login', {
method: 'POST',
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify({
'address': address,
'secretKey': 'your_secret_key_here' // Replace with secret key
})
});
const data = await response.json();
if (data.error) {
throw new Error(data.error);
}
const accountData = await accounts.getAccount(address);
console.log(Wallet address belongs to user: ${accountData.address});
} catch (error) {
console.error(error);
}
}
In this example, we make a POST request to the /api/login endpoint using the user’s wallet address and secret key. The response contains an “accountData” object containing the account information. We then compare the provided address to the addresses in your application’s database or storage system.
Conclusion
Verifying that a user’s wallet address belongs to them using the MetaMask API requires some basic knowledge of the endpoint, authentication flow, and comparison logic. By following this article and implementing the suggested code examples, you should be able to authenticate your application’s users with MetaMask and verify that their wallet addresses belong to them.