test_tlv_debugging.py

from unittest import TestCase
from tlv_debugging import TlvDebugging

class TestHeaderObj(TestCase):
    def test_read(self):
        tlv = TlvDebugging.from_bytes(bytearray([0x69, 0x01, 0x01, 0x5F, 0x00]))
        assert tlv.file_hdr0[0].tag == 105
        assert tlv.file_hdr0[0].length == 1
        assert tlv.file_hdr0[0].body == False

        assert tlv.file_hdr0[1].tag == 95
        assert tlv.file_hdr0[1].length == 0

tlv_debugging.ksy

meta:
  id: tlv_debugging
  file-extension: hex
  endian: le
  encoding: ascii
seq:
  - id: file_hdr0
    type: header_obj
    repeat: until
    repeat-until: _.length == 0
types:
  header_obj:
    seq:
      - id: tag
        type: u1
      - id: multi_byte_len_flag
        type: b1
      - id: length
        type: b7
      - id: body
        size: length
        type:
          switch-on: tag
          cases:
            95:  tb
            105: b1
    types:
      tb: 
        seq:
          - id: no_value
            size: 0

tlv_debugging.py

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

from pkg_resources import parse_version
from kaitaistruct import __version__ as ks_version, KaitaiStruct, KaitaiStream, BytesIO


if parse_version(ks_version) < parse_version('0.7'):
    raise Exception("Incompatible Kaitai Struct Python API: 0.7 or later is required, but you have %s" % (ks_version))

class TlvDebugging(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.file_hdr0 = []
        i = 0
        while True:
            _ = self._root.HeaderObj(self._io, self, self._root)
            self.file_hdr0.append(_)
            if _.length == 0:
                break
            i += 1

    class HeaderObj(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.tag = self._io.read_u1()
            self.multi_byte_len_flag = self._io.read_bits_int(1) != 0
            self.length = self._io.read_bits_int(7)
            self._io.align_to_byte()
            _on = self.tag
            if _on == 95:
                self._raw_body = self._io.read_bytes(self.length)
                io = KaitaiStream(BytesIO(self._raw_body))
                self.body = self._root.HeaderObj.Tb(io, self, self._root)
            elif _on == 105:
                self.body = self._io.read_bits_int(1) != 0
            else:
                self.body = self._io.read_bytes(self.length)

        class Tb(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.no_value = self._io.read_bytes(0)