.chg file format of MONOMAKH-SAPR: Python parsing library

CHG is a container format file used by MONOMAKH-SAPR, a software package for analysis & design of reinforced concrete multi-storey buildings with arbitrary configuration in plan.

CHG is a simple container, which bundles several project files together.

Written and tested by Vladimir Shulzhitskiy, 2017

Application

MONOMAKH-SAPR

File extension

chg

KS implementation details

License: CC0-1.0
Minimal Kaitai Struct required: 0.7

This page hosts a formal specification of .chg file format of MONOMAKH-SAPR using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.

The Python runtime library can be installed from PyPI:

python3 -m pip install kaitaistruct

Code

Parse a local file and get structure in memory:

data = MonomakhSaprChg.from_file("path/to/local/file.chg")

Or parse structure from a bytes:

from kaitaistruct import KaitaiStream, BytesIO

raw = b"\x00\x01\x02..."
data = MonomakhSaprChg(KaitaiStream(BytesIO(raw)))

After that, one can get various attributes from the structure by invoking getter methods like:

data.title # => get title

Python source code to parse .chg file format of MONOMAKH-SAPR

monomakh_sapr_chg.py

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

from pkg_resources import parse_version
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO


if parse_version(kaitaistruct.__version__) < parse_version('0.9'):
    raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))

class MonomakhSaprChg(KaitaiStruct):
    """CHG is a container format file used by
    [MONOMAKH-SAPR](https://www.liraland.com/mono/index.php), a software
    package for analysis & design of reinforced concrete multi-storey
    buildings with arbitrary configuration in plan.
    
    CHG is a simple container, which bundles several project files
    together.
    
    Written and tested by Vladimir Shulzhitskiy, 2017
    """
    def __init__(self, _io, _parent=None, _root=None):
        self._io = _io
        self._parent = _parent
        self._root = _root if _root else self
        self._read()

    def _read(self):
        self.title = (self._io.read_bytes(10)).decode(u"ascii")
        self.ent = []
        i = 0
        while not self._io.is_eof():
            self.ent.append(MonomakhSaprChg.Block(self._io, self, self._root))
            i += 1


    class Block(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            self._io = _io
            self._parent = _parent
            self._root = _root if _root else self
            self._read()

        def _read(self):
            self.header = (self._io.read_bytes(13)).decode(u"ascii")
            self.file_size = self._io.read_u8le()
            self.file = self._io.read_bytes(self.file_size)