experimental-accounting-api/accounting/__init__.py
2013-12-11 00:25:16 +01:00

278 lines
8.1 KiB
Python

import sys
import subprocess
import logging
import time
from datetime import datetime
from xml.etree import ElementTree
from contextlib import contextmanager
_log = logging.getLogger(__name__)
class Ledger:
def __init__(self, ledger_file=None, ledger_bin=None):
if ledger_file is None:
raise ValueError('ledger_file cannot be None')
self.ledger_bin = ledger_bin or 'ledger'
self.ledger_file = ledger_file
_log.info('ledger file: %s', ledger_file)
self.locked = False
self.ledger_process = None
@contextmanager
def locked_process(self):
if self.locked:
raise RuntimeError('The process has already been locked,'
' something\'s out of order.')
# XXX: This code has no purpose in a single-threaded process
timeout = 5 # Seconds
for i in range(1, timeout + 2):
if i > timeout:
raise RuntimeError('Ledger process is already locked')
if not self.locked:
break
else:
_log.info('Waiting for one second... %d/%d', i, timeout)
time.sleep(1)
process = self.get_process()
self.locked = True
_log.debug('Lock enabled')
yield process
self.locked = False
_log.debug('Lock disabled')
def assemble_arguments(self):
return [
self.ledger_bin,
'-f',
self.ledger_file,
]
def init_process(self):
_log.debug('Starting ledger process...')
self.ledger_process = subprocess.Popen(
self.assemble_arguments(),
stdout=subprocess.PIPE,
stdin=subprocess.PIPE,
stderr=subprocess.PIPE)
# Swallow the banner
with self.locked_process() as p:
self.read_until_prompt(p)
return self.ledger_process
def get_process(self):
return self.ledger_process or self.init_process()
def read_until_prompt(self, p):
output = b''
while True:
line = p.stdout.read(1) # XXX: This is a hack
output += line
if b'\n] ' in output:
_log.debug('Found prompt!')
break
output = output[:-3] # Cut away the prompt
_log.debug('output: %s', output)
return output
def send_command(self, command):
output = None
with self.locked_process() as p:
if isinstance(command, str):
command = command.encode('utf8')
p.stdin.write(command + b'\n')
p.stdin.flush()
output = self.read_until_prompt(p)
self.ledger_process.send_signal(subprocess.signal.SIGTERM)
_log.debug('Waiting for ledger to shut down')
self.ledger_process.wait()
self.ledger_process = None
return output
def add_transaction(self, transaction):
transaction_template = ('\n{date} {t.payee}\n'
'{postings}')
posting_template = (' {account} {p.amount.symbol}'
' {p.amount.amount}\n')
output = b''
output += transaction_template.format(
date=transaction.date.strftime('%Y-%m-%d'),
t=transaction,
postings=''.join([posting_template.format(
p=p,
account=p.account + ' ' * (
80 - (len(p.account) + len(p.amount.symbol) +
len(p.amount.amount) + 1 + 2)
)) for p in transaction.postings])).encode('utf8')
with open(self.ledger_file, 'ab') as f:
f.write(output)
_log.debug('written to file: %s', output)
def bal(self):
output = self.send_command('xml')
if output is None:
raise RuntimeError('bal call returned no output')
accounts = []
xml = ElementTree.fromstring(output.decode('utf8'))
accounts = self._recurse_accounts(xml.find('./accounts'))
return accounts
def _recurse_accounts(self, root):
accounts = []
for account in root.findall('./account'):
name = account.find('./fullname').text
amounts = []
# Try to find an account total value, then try to find the account
# balance
account_amounts = account.findall(
'./account-total/balance/amount') or \
account.findall('./account-amount/amount') or \
account.findall('./account-total/amount')
if account_amounts:
for amount in account_amounts:
quantity = amount.find('./quantity').text
symbol = amount.find('./commodity/symbol').text
amounts.append(Amount(amount=quantity, symbol=symbol))
else:
_log.warning('Account %s does not have any amounts', name)
accounts.append(Account(name=name,
amounts=amounts,
accounts=self._recurse_accounts(account)))
return accounts
def reg(self):
output = self.send_command('xml')
if output is None:
raise RuntimeError('reg call returned no output')
entries = []
reg_xml = ElementTree.fromstring(output.decode('utf8'))
for transaction in reg_xml.findall('./transactions/transaction'):
date = datetime.strptime(transaction.find('./date').text,
'%Y/%m/%d')
payee = transaction.find('./payee').text
postings = []
for posting in transaction.findall('./postings/posting'):
account = posting.find('./account/name').text
amount = posting.find('./post-amount/amount/quantity').text
symbol = posting.find(
'./post-amount/amount/commodity/symbol').text
postings.append(
Posting(account=account,
amount=Amount(amount=amount, symbol=symbol)))
entries.append(
Transaction(date=date, payee=payee, postings=postings))
return entries
class Transaction:
def __init__(self, date=None, payee=None, postings=None):
self.date = date
self.payee = payee
self.postings = postings
def __repr__(self):
return ('<{self.__class__.__name__} {date}' +
' {self.payee} {self.postings}').format(
self=self,
date=self.date.strftime('%Y-%m-%d'))
class Posting:
def __init__(self, account=None, amount=None):
self.account = account
self.amount = amount
def __repr__(self):
return ('<{self.__class__.__name__} "{self.account}"' +
' {self.amount}>').format(self=self)
class Amount:
def __init__(self, amount=None, symbol=None):
self.amount = amount
self.symbol = symbol
def __repr__(self):
return ('<{self.__class__.__name__} {self.symbol}' +
' {self.amount}>').format(self=self)
class Account:
def __init__(self, name=None, amounts=None, accounts=None):
self.name = name
self.amounts = amounts
self.accounts = accounts
def __repr__(self):
return ('<{self.__class__.__name__} "{self.name}" {self.amounts}' +
' {self.accounts}>').format(self=self)
def main(argv=None):
import argparse
if argv is None:
argv = sys.argv
parser = argparse.ArgumentParser()
parser.add_argument('-v', '--verbosity',
default='INFO',
help=('Filter logging output. Possible values:' +
' CRITICAL, ERROR, WARNING, INFO, DEBUG'))
args = parser.parse_args(argv[1:])
logging.basicConfig(level=getattr(logging, args.verbosity, 'INFO'))
ledger = Ledger(ledger_file='non-profit-test-data.ledger')
print(ledger.bal())
print(ledger.reg())
if __name__ == '__main__':
sys.exit(main())