A versatile and extensible binary data parsing/serializing library for Python 3

supyr_struct, binary, data, structure, parser, serializer, serialize
pip install supyr-struct==1.5.4


Supyr Struct

Supyr Struct is an extensible and powerful binary data parsing, editing, and serializing library for Python 3.

Supyr's parsing and serializing is declarative, meaning that rather than write code to handle parsing and serializing data, you instead piece together a description of the structure using various FieldTypes. These descriptions are used by BlockDef objects to build Blocks, which represent/contain the parsed data. A BlockDef is simply a constructor object that scans its description for errors on initialization and uses it for creating Blocks.

Supyr provides a large collection of FieldTypes, ranging from atomic data types(floats and ints of various sizes) to hierarchical structures(structs, containers, and arrays) and logical structures and wrappers(switches and unions).

For a detailed overview of the more abstract concepts and features of Supyr, read the text files in the 'docs' folder.


Check out the changelog here.


This project is licensed under the MIT License, check out the details and author info here.


You'll need Python 3.5 or higher.

In your terminal execute:

python3 -m pip install supyr_struct

or, you can clone/download this repo and run the

git clone
cd supyr_struct
python3 -m pip install .


Heres a small example of defining a structure using a BlockDef and FieldTypes and using it to create a Block.

>>> from supyr_struct import *

>>> asdf = BlockDef('some_block',
... UInt32('some_int'),
... BytesRaw('some_bytes', SIZE=16),
... ENDIAN='>')

>>> test_block =
>>> test_block.some_int = 1337
>>> test_block.some_bytes = b'heres a cstring\x00'

>>> print(test_block)
... [ Container, entries:2, some_block
... [ UInt32, size:4, some_int, 1337 ]
... [ BytesRaw, size:16, some_bytes, <rawdata> ]
... ]

>>> test_block.serialize()
... bytearray(b'\x00\x00\x059heres a cstring\x00')

Supyr allows forcing endianness to be either big, little, or back to normal on a library scale and/or on individual FieldTypes.

>>> field_types.FieldType.force_little()
>>> test_block.serialize()
... bytearray(b'9\x05\x00\x00heres a cstring\x00')
>>> field_types.FieldType.force_normal()
>>> test_block.serialize()
... bytearray(b'\x00\x00\x059heres a cstring\x00')
>>> field_types.BUInt32.force_little()
>>> test_block.serialize()
... bytearray(b'9\x05\x00\x00heres a cstring\x00')

Take a look at the examples module for some ready-to-run example programs that utilize Supyr in different ways.

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