compression_test2.py

#!/usr/bin/env python
# Author Dario Clavijo 2016

import zlib
import bz2
import fileinput
import struct

zlib_magic = "ZLIB"


def ser_uint(i):
    return hex(i).replace("0x", "").replace("L", "").zfill(8).decode("hex")


def deser_uint(s):
    return int(s.encode("hex"), 16)


def test(msg_data):

    print("Criginal data:", msg_data)

    msg_data = zlib.compress(msg_data, 1)

    print("Compressed data(hex): " + msg_data.encode("hex"))

    msg_data = struct.pack(
        ">4si{0:d}s".format(len(msg_data)), zlib_magic, len(msg_data), msg_data
    )
    # msg_data = "ZLIB%s%s" % (ser_uint(len(msg_data)),msg_data)

    print("Packed data: " + msg_data.encode("hex"))

    if msg_data[:4] == zlib_magic:
        msg_len = deser_uint(msg_data[4:8])
        print("msg_len: {0!s}".format(msg_len))

        a, b, c = struct.unpack(">4si{0:d}s".format(msg_len), msg_data)
        print("Pack:", a, b, c.encode("hex"))
        new_data = zlib.decompress(c)
        print(f"Decompressed data: {new_data}")


test("dario")