commit 222ef8b421bbade27c1745be4a5b3c690298d2e6
Author: Joar Wandborg <joar@wandborg.se>
Date:   Mon Dec 9 17:54:00 2013 +0100

    Initial commit

diff --git a/accounting/__init__.py b/accounting/__init__.py
new file mode 100644
index 0000000..a10564f
--- /dev/null
+++ b/accounting/__init__.py
@@ -0,0 +1,201 @@
+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:
+            _log.warning('Process is already locked')
+            for i in range(1, 5):
+                if i > 4:
+                    raise RuntimeError('Ledger process is already locked')
+
+                if not self.locked:
+                    break
+                else:
+                    _log.info('Waiting for one second... %d/%d', i, 5)
+                    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:
+            # _log.debug('reading data')
+
+            line = p.stdout.read(1)  # XXX: This is a hack
+            # _log.debug('line: %s', line)
+
+            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, p, command):
+        # TODO: Should be extended to handle the locking and return the output
+        _bytes = p.stdin.write(command + b'\n')
+        p.stdin.flush()
+
+        return _bytes
+
+    def bal(self):
+        output = None
+
+        with self.locked_process() as p:
+            _log.debug('aquired process lock')
+            self.send_command(p, b'bal --format "%A|%t\\\\n"')
+            _log.debug('sent command')
+
+            output = self.read_until_prompt(p)
+
+        if output is None:
+            raise RuntimeError('bal call returned no output')
+
+        accounts = []
+
+        for line in output.split(b'\n'):
+            name, balance =  line.decode('utf8').split('|')
+
+            accounts.append(Account(name=name, balance=balance))
+
+        return accounts
+
+    def reg(self):
+        output = None
+
+        with self.locked_process() as p:
+            _log.debug('aquired process lock')
+            self.send_command(p, b'xml')
+
+            output = self.read_until_prompt(p)
+
+        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, 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.isoformat())
+
+class Posting:
+    def __init__(self, account=None, amount=None, symbol=None):
+        self.account = account
+        self.amount = amount
+        self.symbol = symbol
+
+    def __repr__(self):
+        return ('<{self.__class__.__name__} "{self.account}"' +
+                ' {self.symbol} {self.amount}>').format(self=self)
+
+
+class Account:
+    def __init__(self, name=None, balance=None):
+        self.name = name
+        self.balance = balance
+
+    def __repr__(self):
+        return '<{self.__class__.__name__}: "{self.name}" {self.balance} >'.format(
+            self=self)
+
+
+def main():
+    ledger = Ledger(ledger_file='non-profit-test-data.ledger')
+    print(ledger.bal())
+    print(ledger.reg())
+
+
+if __name__ == '__main__':
+    logging.basicConfig(level=logging.DEBUG)
+    main()
diff --git a/non-profit-test-data.ledger b/non-profit-test-data.ledger
new file mode 100644
index 0000000..f5764a1
--- /dev/null
+++ b/non-profit-test-data.ledger
@@ -0,0 +1,32 @@
+
+2010/01/01 Kindly T. Donor
+   Income:Foo:Donation   $-100.00
+      ;Invoice: Projects/Foo/Invoices/Invoice20100101.pdf
+   Assets:Checking       $100.00
+
+
+2011/03/15 Another J. Donor
+   Income:Foo:Donation   $-400.00
+      ;Approval: Projects/Foo/earmark-record.txt
+   Assets:Checking       $400.00
+
+2011/04/20 (1) Baz Hosting Services, LLC
+   Expenses:Foo:Hosting   $250.00
+      ;Receipt: Projects/Foo/Expenses/hosting/AprilHostingReceipt.pdf
+   Assets:Checking       $-250.00
+
+2011/05/10 Donation to General Fund
+   Income:Donation   $-50.00
+      ;Invoice: Financial/Invoices/Invoice20110510.pdf
+   Assets:Checking   $50.00
+
+2011/04/20 (2) Baz Hosting Services, LLC
+   Expenses:Blah:Hosting   $250.00
+      ;Receipt: Projects/Blah/Expenses/hosting/AprilHostingReceipt.pdf
+      ;Invoice: Projects/Blah/Expenses/hosting/april-invoice.pdf
+   Assets:Checking       $-250.00
+      ;Statement: Financial/BankStuff/bank-statement.pdf
+
+2011-04-25 A transaction with ISO date
+   Income:Karma              KARMA-10
+   Assets:Karma Account      KARMA 10