ledgerparser

ledgerparser.py

"""ledger journal parser

We use this to parse the ledger file because we want to preserve the
exact format of the file including spaces, etc.  It maps the parsed
transaction to the origin lines of the file.

"""
import ledger


def include_lines(ledger_file, xacts):
    """Generator to match the journal lines with the xact"""
    journal_lines = enumerate(ledger_file, 1)
    for xact in xacts:
        lines = []
        while True:
            linenum, line = next(journal_lines)
            lines.append(line)
            if linenum == xact.pos.end_line:
                break
        yield lines, xact


def include_trailing_lines(ledger_file, xacts):
    """Generator to add any trailing lines to the last transaction's lines"""
    prev = None
    for lines, xact in xacts:
        if prev:
            yield prev
        prev = lines, xact
    if prev:
        lines, xact = prev
        lines += list(ledger_file)
        yield lines, xact


def parse_xacts(ledger_file):
    session = ledger.Session()
    xacts = session.read_journal_from_string(ledger_file.read()).xacts()
    ledger_file.seek(0)
    xacts = include_lines(ledger_file, xacts)
    xacts = include_trailing_lines(ledger_file, xacts)
    return xacts