python get uncompressed size of a .gz file

get_uncompressed_size.py

    def get_uncompressed_size(self, file):
        fileobj = open(file, 'r')
        fileobj.seek(-8, 2)
        crc32 = gzip.read32(fileobj)
        isize = gzip.read32(fileobj)  # may exceed 2GB
        fileobj.close()
        return isize

taken from gzip.py

Hi @ozanturksever,
I think I am searching for exactly this functionality. I do have to know how large a file will be after decompressing and unpacking it. How come this coding does work and show me the same result as ?

> gzip -lv mongodb.tar
method  crc     date  time    compressed uncompressed  ratio uncompressed_name
defla cfdff20d Mar 10 15:25      3037694   3102720000  99.9% mongodb.tar

How does this work?

@fabianschwarzfritz

def get_uncompressed_size(file):
    pipe_in = os.popen('gzip -l %s' % file)
    list_1 = pipe_in.readlines()
    list_2 = list_1[1].split()
    c , u , r , n = list_2
    return int(u)

Source: https://bytes.com/topic/python/answers/36089-uncompressed-size-gz-file

import gzip

def get_uncompressed_size(FileName):
    with gzip.open(FileName, 'rb') as fd:
        fd.seek(0, 2)
        size = fd.tell()
    return size