Here is an article on how to sign a message with a private key using Bitcoin in TypeScript.
Signing messages with private keys in Bitcoin
In this article, we will show you how to create a private key from your seed phrase using the bitcoinjs-lib library and then use it to sign messages. We will also show you how to bind the private key to the btcAddress and nftAddress endpoints of our application.
Step 1: Create a private key
First, you need to create a private key from your seed phrase. You can do this by running the following command in your terminal:
bc -l < seed_phrase_file_path > private_key.pem
Replace
Step 2: Import Libraries and Load Private Key
Next, we need to import the bitcoinjs-lib library and load our private key:
import * as bitcoin from 'bitcoinjs-lib';
import * as ecc from 'tiny-secp256k1';
const privateKey = await require('./private_key.pem');
Step 3: Create a message to sign
Create a message that you want to sign. For example, let’s say we have a contract address for an NFT and a recipient address:
const contractAddress = '0x...'; // Replace with the contract address
const recipientAddress = '0x...'; // Replace with the recipient address
Step 4: Sign the message
Now we can create an instance of BitcoinMessage from our message and private key:
const BitcoinMessage = require('bitcoinjs-lib').BitcoinMessage;
const bitcoinMessage = new BitcoinMessage({
contractedaddress,
recipientAddress,
data: 'Hello, world!',
});
const signature = await bitcoin.signMessage(privateKey, {
address: BitcoinMessage.Address.BTC,
network: BitcoinNetwork.MINECONomy,
});
Step 5: Bind the private key to the endpoints
Finally, we need to bind our private key to the btcAddress and nftAddress endpoints of our application:
“`typescript
const bitcoin = require(‘bitcoinjs-lib’);
const ecc = require(‘tiny-secp256k1’);
// Define endpoints
const contractEndpoint = ‘
const recipientEndpoint = ‘
// Create a private key from the seed phrase file
const privateKey = await require(‘./private_key.pem’);
// Load our private key
const bitcoinPrivateKey = await ecc.keyFromPrivate(privateKey);
// Bind the private key to the endpoints
asynchronous function getEndpoint(privateKey) {
const contract = new BitcoinMessage({
contractaddress,
data: ‘Hello world!’,
});
const signature = await bitcoin.signMessage(privateKey, {
address: BitcoinMessage.Address.BTC,
network: BitcoinNetwork.MINECONomy,
});
return { contract, signature };
}
async function getContractEndpoint(privateKey) {
// Create a private key from the seed phrase file
const privateKey = await require(‘./private_key.pem’);
const bitcoinPrivateKey = await ecc.keyFromPrivate(privateKey);
// Load our private key
const bitcoin = require(‘bitcoinjs-lib’);
// Bind the private key to the contract endpoint
return new Promise((resolve, reject) => {
getEndpoint(privateKey).then((data) => {
resolve(data);
}).catch((error) => {
reject(error);
});
});
}
async function getRecipientEndpoint(privateKey) {
// Create a private key from the seed phrase file
const privateKey = await require(‘./private_key.pem’);
const bitcoinPrivateKey = await ecc.keyFromPrivate(privateKey);
// Load our private key
const bitcoin = require(‘bitcoinjs-lib’);
// Bind the private key to the recipient endpoint
return new Promise((resolve, reject) => {
getEndpoint(privateKey).then((data) => {
resolve({contract: data.contract, signature: data.signature});
}).