Getting Error while trying to decode psbt base64 to json using bitcoinjs/bip174 library

Question

const base64PSBT = 'base_64';

// Decode the base64 PSBT to a Buffer
const psbtBuffer = Buffer.from(base64PSBT, 'base64');

// Parse the PSBT
const psbt = bip174.Psbt.fromBuffer(psbtBuffer);

// Convert the PSBT to a JSON object
const psbtJSON = psbt.data;

console.log(JSON.stringify(psbtJSON, null, 2));

error: const unsignedTx = txGetter(unsignedTxMaps[0].value); ^ TypeError: txGetter is not a function

Answer 1

The problem is that in addition to the buffer (denoted as psbtBuffer in the code you provided), it is necessary to pass the txGetter function as a second parameter to the fromBuffer function. If you don't do this, javaScript considers the second parameter as undefined so that later calls to the given function (const unsignedTx = txGetter(unsignedTxMaps[0].value);) will not be possible.

The README says the following:

// This will parse the PSBT, and use the function you pass to parse the Transaction part
// the function should throw if the scriptSig section is not empty
const psbt = Psbt.fromBuffer(somePsbtBuffer, pTxFromBuffer)