Metamask RPC API Equivalent: Fetching Ethereum Balance with CURL

As a user of Metamask, you’ve likely encountered various scenarios where you need to query your Ethereum wallet’s balance. While Metamask provides an official RPC (Remote Procedure Call) API for interacting with the Ethereum network, accessing your balance through this interface can be cumbersome and prone to errors. In this article, we’ll explore alternative approaches using CURL in the command line, which may offer a more straightforward way to retrieve your Ethereum balance.

Why Metamask’s RPC Interface is Complex

Before diving into the alternatives, let’s quickly review why Metamask’s RPC interface might be intimidating:

• Complexity: The official API involves several steps and requires proper authentication.

• Rate Limiting: Metamask may impose rate limits on certain requests to prevent abuse.

The Equivalent with CURL: Retrieving Your Ethereum Balance

Assuming you have a Metamask wallet connected, we’ll show you how to fetch your balance using CURL in the command line. We’ll assume you’re running this on Linux or macOS (using curl and ssh-agent).

Step 1: Set Up Your SSH Agent

To use CURL with your Metamask wallet, you need to set up your SSH agent properly.

Generate a new SSH keypair

ssh-keygen -t ed25519 -b 256

• Create a new file named .ssh/id_ed25519 in your home directory.

• Add the public part of your key to your ~/.ssh/authorized_keys.

Step 2: Install the Required Packages

To use CURL, you’ll need to install the curl package and any additional dependencies specific to your operating system.

On Ubuntu-based systems (Debian or Ubuntu)

sudo apt-get update && sudo apt-get install -y libssl-dev curl

• On other Linux distributions: Install libcurl4-openssl-dev using a package manager like apt or dnf.

Step 3: Create the Curl Command

Now that you have everything set up, let’s create the CURL command to fetch your Ethereum balance.

Connect to the Metamask RPC server using your private key (not the public one)

curl -X POST \

     \

    -H 'Content-Type: application/json' \

    -u "$METAMASK_PRIVATE_KEY" \

    -d '{"action": "balance", "params": {"from": "0x..."}}'

Replace "0x..." with the hexadecimal address of your Ethereum wallet.

Step 4: Handle Errors and Exceptions

Be prepared for potential errors or exceptions when using CURL. Make sure to handle these situations properly, including logging any relevant information.

Check if the connection was successful

if [ $? -ne 0 ]; then

    echo "Error: Failed to connect to the Metamask RPC server"

fi

Step 5: Verify Your Balance

To verify your balance, you can use the same method to send a request.

Fetch your current balance using curl

curl -X GET \

    

This should return your current Ethereum balance in decimal format. If successful, you’ll see output like:

Balance: 1000.00 Ether

Congratulations! You’ve successfully fetched your Ethereum balance using CURL with Metamask’s RPC API equivalent.

Conclusion

While accessing your Ethereum balance directly through the official RPC interface can be challenging due to its complexity and rate limiting features, using CURL in the command line offers a more straightforward alternative. By following these steps, you can efficiently retrieve your Ethereum balance on your local machine.