Understanding signing messages with bitcoinjs-lib

I’m trying to understand what a specific line of code does when signing a message using bitcoinjs-lib. Here’s the code:

var bitcoin = require('bitcoinjs-lib') var bitcoinMessage = require('bitcoinjs-message')  var keyPair = bitcoin.ECPair.makeRandom(); //private key var privateKey = keyPair.toWIF(); // Address var address = keyPair.getAddress();  console.log(privateKey); console.log(address);  privateKey = keyPair.d.toBuffer(32) var message = 'your message' var messagePrefix = bitcoin.networks.bitcoin.messagePrefix  var signature = bitcoinMessage.sign(message, messagePrefix, privateKey, keyPair.compressed) console.log(signature.toString('base64')) 

The line I’m curious about is this one:

privateKey = keyPair.d.toBuffer(32) 

What exactly is this code doing and why is it necessary?

Thanks,

Connor

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How to use bitcoinjs-lib with Regtest?

I was trying to use the bitcoinjs-lib (1) with my regtest network. More specifically I was trying to build a tx with TransactionBuilder but it gave me a ‘transaction has no matching Script’ exception.

In a closed github issue (2) I find out that it’s possible to specify the network (network.testnet), but I can’t find any documentation related to regtest. I just want to create and broadcast a raw tx created with bitcoinjs to my regtest network.

So, has anyone talked to a regtest network with bitcoinjs-lib successfully? If not, what other libs would you recommend for the satoshi client? Thanks.

(1) https://github.com/bitcoinjs/bitcoinjs-lib

(2) https://github.com/bitcoinjs/bitcoinjs-lib/issues/500

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Send a transaction using bitcoinjs-lib to testnet in a box

I put together some code using bitcoinjs-lib which allows me to create a testnet transaction and send some bitcoins from one address to another.

But I’m getting tired of waiting for 10 mins after every test. I’d like to be able to test my code a bit faster.

I set up testnet-in-a-box in a virtual machine and have played around with a few commands and it works fine.

But when I try to send a transaction to one of the nodes at 127.0.0.1:19000 it gives me an error saying:

{ [Error: socket hang up] code: 'ECONNRESET' } 

I’m broadcasting the transaction as shown here using:

blockchain.t.transactions.propagate(tx.build().toHex(), done) 

What am I doing wrong? Is it not possible to submit transactions to the node in testnet-in-a-box?

Any help will be appreciated! Thanks!

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