piecash 0.1.3

An augmented SQLAlchemy layer for a pythonic CRUD interface to GnuCash SQL documents.

Project

This project provides a simple and pythonic CRUD interface to a GnuCash Book stored in SQL (sqlite3 or Postgres). It is a pure python package relying on SQL Alchemy. It can be used as an alternative to: - the official python bindings (if no advanced engine calculations are needed) - XLST transformations of the XML GnuCash document

It is basically a SQLAlchemy layer augmented with methods to ease the manipulation of the GnuCash objects.

Project is in early development. Knowledge of SQLAlchemy is at this stage a probably required to use it and/or to contribute to it. Some documentation for developers on the object model of GnuCash as understood by the author is available here.

Installation

From pip:

$ pip install piecash

Usage

The simplest workflow to use piecash is first to open a SQLAlchemy session to a GnuCash Book

import piecash

# open a GnuCash Book
book = piecash.connect_to_gnucash_book("test.gnucash", readonly=True)
session = book.get_session()

Use the SQLAlchemy session to query the Book, for example to query the stock prices

# example 1, print all stock prices in the Book
# display all prices
for price in session.query(piecash.Price).all():
    print "{}/{} on {} = {} {}".format(price.commodity.namespace,
                                       price.commodity.mnemonic,
                                       price.date,
                                       float(price.value_num) / price.value_denom,
                                       price.currency.mnemonic,
                                       )

NASDAQ/CZR on 2014-11-12 14:27:00 = 13.65 USD
...

or to query the accounts:

for account in session.query(piecash.Account).all():
    print account

Account<>
Account<Assets>
Account<Assets:Current Assets>
Account<Assets:Current Assets:Checking Account>
Account<Assets:Current Assets:Savings Account>
Account<Assets:Current Assets:Cash in Wallet>
Account<Liabilities>
Account<Liabilities:Credit Card>
Account<Income>
Account<Income:Bonus>
Account<Income:Gifts Received>
...

or to create a new account below some existing account:

# build map between account fullname (e.g. "Assets:Current Assets" and account)
map_fullname_account = {account.fullname():account for account in session.query(piecash.Account).all()}

# use it to retrieve the current assets account
acc_cur = map_fullname_account["Assets:Current Assets"]

# retrieve EUR currency
EUR = session.query(piecash.Commodity).filter_by(mnemonic='EUR')

# add a new subaccount to this account of type ASSET with currency EUR
piecash.Account(name="new savings account", account_type="ASSET", parent=acc_cur, commodity=EUR)

# save changes
session.commit()

Most basic objects used for personal finance are supported (Account, Split, Transaction, Price, …).

A more complete example showing interactions with an existing GnuCash Book created from scratch in GnuCash is available in the tests/ipython subfolder as ipython notebook (ipython session)

To do:

• write more tests

• implement higher function to offer a higher level API than the SQLAlchemy layer (for instance return a Book instead of SA session, be able to do Book.currencies to return session.query(piecash.Commodity).filter(Commodity.namespace == “CURRENCY”).all())

• review non core objects (model_budget, model_business)

• write example scripts

• improve KVP support

Authors

• sdementen