String GZIP

sgzip.py

#!/usr/bin/env python
# encoding: utf-8

"""
GZIP for String
https://www.ietf.org/rfc/rfc1952.txt

Yes, I know gzip buildin module
"""
import logging
logger = logging.getLogger(__name__)
import zlib
import struct
import time


GZIP_HEAD_STRUCT = '>ili'
GZIP_FOOT_STRUCT = '<LL'
GZIP_MAGIC = 0x1f8b0808 # No FTEXT/FHCRC/FEXTRA/FNAME/FCOMMENT
GZIP_XFLOS_MAGIC = 0x00036d00 # compress fast = 4, 03 = UNIX, 6d = filename, 00 end
UNSIGNED_32_MASK = 0xffffffffL


def encode(data=''):
     
    if data:
        size = len(data)
        crc = zlib.crc32(data, 0L)
        gzip_head = struct.pack(GZIP_HEAD_STRUCT,
                               GZIP_MAGIC,
                               long(time.time()),
                               GZIP_XFLOS_MAGIC)
        print "HEAD", gzip_head.encode('hex')
        gzip_body = zlib.compress(data)
        gzip_foot = struct.pack(GZIP_FOOT_STRUCT,
                                crc & UNSIGNED_32_MASK,
                                size & UNSIGNED_32_MASK) 

        print "FOOT", gzip_foot.encode('hex')
        return gzip_head + gzip_body + gzip_foot


    return