Parses GNUCash XML documents for running queries and performing bulk updates

For as long as I've been using GNUCash, people have been crying out for a way to bulk-edit transactions, usually because they've decided they need to restructure the way they represent transactions and need to separate a group of them out to a new account long after they've been entered / imported.

It's painfully clear the GNUCash devs have no intention of implementing this feature. Yes, once you've got your cashbook set up properly (read: have already learned this lesson the hard way) the need to do this generally lessens, but until you have, needing to edit 50+ transactions manually is tedious and error prone. Every time I've done it I've ended up sending at least one transaction to the wrong account, or changing the wrong split.

Always make a backup of your GNUCash file before using this. It is not widely tested. It might break on complicated cashbooks. It might fail in subtle ways. This is just a tool I made to get me out of a jam, and I'm sharing it in case it can help you too.

Don't just make a backup. Check your trial balances before and after using this tool to make sure only the changes you made have been applied.

You'll need Node.js and npm installed.

Save your GNUCash book as an uncompressed XML file. You can turn off compression in GNUCash Preferences -> General -> Compress Files

Clone this repo, and copy your cashbook to the examples folder. Edit the sample example.js file with the name of your file, and modify the query to suit your situation.

A simple example cashbook is in examples/simple.gnucash. The person has two source of income: $20.00 per week from a paper run, and $50.00 per week from a flour mill. They want to keep these sources of income in two separate accounts: Income:Paper Run and Income:Flour Mill.

Unfortunately, some of the transactions from the Flour Mill are still mixed in with those from the Paper Run. We want to move only those transactions to the correct account:

// read the contents of an uncompressed XML file
const buffer = fs.readFileSync('simple.gnucash');
// … and parse into a `Book` object
const book = gnucash.Book.deserialize(buffer);

// Find all the transactions in 'Income:Paper Run' for $50.00 between April 1 and June 3
// and move them to the 'Income:Flour Mill' account
book.transactionQuery()
  .withDateRange('2022-04-01', '2022-06-30')
  .havingSplits((splits) => splits
    .withAccountName('Income:Paper Run')
    .withValue('-5000/100')
    .setAccount(book.findAccountByName('Income:Flour Mill')));

// …and save it to a new file
fs.writeFileSync('simple-out.gnucash', book.serialize());

Sorry, this is just a simple tool I made to get myself out of a jam, not a fully-fledged tool with a nice user interface.

Maybe one day someone will make one using this library. Until then, maybe you can find someone familiar with Javascript to help you.