transaction charges – Switch all funds to a different pockets with node.js

Relating to first query,

No, you do not have to run your personal node. What I do know is blockstream esplora gives public API with documentation you possibly can work with.

Relating to second query,

It depends upon what sort of segwit handle(p2wpkh, p2wsh, p2tr) it’s, however I suppose what you need to spend can be the most typical segwit transaction, which is p2wpkh(single signature with public key).

For p2wpkh segwit spend, you possibly can refer beneath code working for nodejs, which you will discover right here, too.

import * as bitcoin from 'bitcoin-sdk-js';

const privkey =
  'e6c58327b4bf1314296bba7adb66f94c36ea5611ac07830c229aa7ee6f9caac3';
const toAddress="tb1qmjqyknun9umlwlle5nuy8jz9ms7v85cp7k2nfe";
const toValue = 300000; // unit is satoshi
const txHash="8bcd197873dbff5cc67cb3e0b1cbbdf097c7af94b0e9365adecb424e408294bf";
const inputValue = 310981; // payment is enter worth - complete worth

const tx = new bitcoin.Transaction();

await tx.addInput({
  txHash: txHash,
  index: n, // it needs to be vout of utxo, index of utxo in transation
  worth: inputValue,
});
await tx.addOutput({
  handle: toAddress,
  worth: toValue,
});
await tx.signInput(privkey, 0);

const txHex = await tx.getSignedHex();

For different kind of segwit handle, it actually varies on unlocking script, so there’s not likely a method answer for it.