packetutil 0.1.2

Utility to pack and unpack binary data into commonly used python data types.

packetutil

packetutil is a Python utility library for defining and manipulating custom binary packet structures using flexible field definitions. It makes it easy to pack Python dictionaries into bytearrays and unpack bytearrays back into structured data — with support for bitfields, bytearrays, and typed fields.

Features

• Define binary packet formats with intuitive field objects
• Convert Python dictionaries to binary with pack()
• Decode binary into dictionaries with unpack()
• Supports:
  • Typed fields (uint8, uint16, etc.)
  • Fixed-size byte arrays
  • Bitfields with named subfields and bit lengths

Installation

pip install packetutil

Usage

Define your packet structure

from packetutil import PacketFormatter, TypeField, BytearrayField, BitField

fields = {
    'type_f': TypeField('uint16', big_endian=False),
    'byte_f': BytearrayField(4),
    'bit_f': BitField('uint16', {
        'field1': 3,
        'field2': 6,
        'field3': 7
    })
}
formatter = PacketFormatter(fields)

Pack data into a bytearray

data = {
    'type_f': 1,
    'byte_f': bytearray(4 * [0]),
    'bit_f': {
        'field1': 7,
        'field2': 20,
        'field3': 30
    }
}

packed = formatter.pack(data)
print(packed)
# Output:
# bytearray([0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0xEA, 0x1E])

Unpack a bytearray into structured data

parsed = formatter.unpack(bytearray([0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0xEA, 0x1E]))
print(parsed)
# Output:
# {
#     'type_f': 1,
#     'byte_f': bytearray([0, 0, 0, 0]),
#     'bit_f': {
#         'field1': 7,
#         'field2': 20,
#         'field3': 30
#     }
# }