Creating a Multi-Blockchain Wallet in Python for Ethereum and Bitcoin Testnets

Introduction to Multi-Blockchain Wallets

This guide demonstrates how to build a universal cryptocurrency wallet in Python capable of managing hundreds of cryptocurrencies and billions of addresses. Specifically, we'll generate wallets for Ethereum and Bitcoin Testnet environments.

Key Features:

• Supports multiple blockchains (e.g., Ethereum, Bitcoin Testnet)
• Generates hierarchical deterministic (HD) wallets for enhanced security
• Enables seamless transaction management

Prerequisites and Setup

Required Dependencies

Ensure the following tools are installed:

1. PHP (any version): Required for the hd-wallet-derive tool.
2. hd-wallet-derive: A hierarchical deterministic wallet utility.

3. Python Libraries:

   • bit: Bitcoin library for Python
   • web3.py: Ethereum interaction library

👉 Download the latest PHP version

Project Initialization

1. Create Project Directory:

   mkdir wallet && cd wallet

2. Clone hd-wallet-derive:

   git clone https://github.com/dan-da/hd-wallet-derive.git

3. Create Symlink:

   ln -s hd-wallet-derive/hd-wallet-derive.php derive

4. Test the Script:
   Verify functionality using examples from the README.md.

Building the Wallet Script

Step 1: Initialize wallet.py

Create a Python script (wallet.py) with the following structure:

from bit import PrivateKeyTestnet
from web3 import Web3
import os

# Constants
BTC_TESTNET = 'btc-test'
ETH = 'eth'

Step 2: Configure Wallet Functions

def priv_key_to_account(coin, priv_key):
    if coin == BTC_TESTNET:
        return PrivateKeyTestnet(priv_key)
    elif coin == ETH:
        return Web3().eth.account.privateKeyToAccount(priv_key)

👉 Explore Ethereum development tools

Executing Transactions

Bitcoin Testnet Transactions

1. Fund Wallet: Use a Bitcoin Testnet faucet to deposit funds.

2. Send Transaction:

   sender = priv_key_to_account(BTCTEST, 'your_privkey_here')
   send_tx(BTCTEST, sender, 'recipient_address', 0.0001)

3. Monitor: Track transactions via a Testnet block explorer.

Ethereum PoA Transactions

1. Pre-fund Accounts: Modify networkname.json to include your ETH address.

2. Initialize Geth:

   geth --datadir node1 init networkname.json

3. Inject PoA Middleware:

   from web3.middleware import geth_poa_middleware
   w3.middleware_onion.inject(geth_poa_middleware, layer=0)

4. Send Transaction:

   eth_sender = priv_key_to_account(ETH, 'your_privkey_here')
   send_tx(ETH, eth_sender, 'recipient_address', 2)

FAQs

1. Why is my Ethereum transaction stuck as "Pending"?

• Solution: Send a dummy transaction via MyCrypto to initialize gas price calculations.

2. How do I resolve "Invalid Private Key" errors?

• Solution: Ensure keys are hex-formatted and include the 0x prefix for Ethereum.

3. Can this wallet support other blockchains?

• Answer: Yes! Integrate additional libraries like pycoin for altcoins.

Conclusion

This Python multi-blockchain wallet provides a scalable solution for managing diverse cryptocurrencies. By leveraging HD wallets and Testnets, developers can securely test transactions before deploying to mainnet.

Key Takeaways:

• Use hd-wallet-derive for unified address management.
• Always test transactions on Testnets first.
• Monitor transactions via block explorers for transparency.

### Keywords:
- Multi-blockchain wallet
- Python cryptocurrency
- Ethereum Testnet
- Bitcoin Testnet
- HD wallet
- web3.py
- bit library
- Transaction automation