gzip a file in Python | 易学教程

问题

I want to gzip a file in Python. I am trying to use the subprocss.check_call(), but it keeps failing with the error 'OSError: [Errno 2] No such file or directory'. Is there a problem with what I am trying here? Is there a better way to gzip a file than using subprocess.check_call?

from subprocess import check_call

def gZipFile(fullFilePath)
    check_call('gzip ' + fullFilePath)

Thanks!!

回答1:

Try this:

check_call(['gzip', fullFilePath])

Depending on what you're doing with the data of these files, Skirmantas's link to http://docs.python.org/library/gzip.html may also be helpful. Note the examples near the bottom of the page. If you aren't needing to access the data, or don't have the data already in your Python code, executing gzip may be the cleanest way to do it so you don't have to handle the data in Python.

回答2:

There is a module gzip. Usage:

Example of how to create a compressed GZIP file:

import gzip
content = b"Lots of content here"
f = gzip.open('/home/joe/file.txt.gz', 'wb')
f.write(content)
f.close()

Example of how to GZIP compress an existing file:

import gzip
f_in = open('/home/joe/file.txt')
f_out = gzip.open('/home/joe/file.txt.gz', 'wb')
f_out.writelines(f_in)
f_out.close()
f_in.close()

EDIT:

Jace Browning's answer using with in Python >= 2.7 is obviously more terse and readable, so my second snippet would (and should) look like:

import gzip
with open('/home/joe/file.txt', 'rb') as f_in, gzip.open('/home/joe/file.txt.gz', 'wb') as f_out:
    f_out.writelines(f_in)

回答3:

In Python 2.7 format:

import gzip

with open("path/to/file", 'rb') as orig_file:
    with gzip.open("path/to/file.gz", 'wb') as zipped_file:
        zipped_file.writelines(orig_file)

Even shorter (Tested on python 2.7.6)

with open('path/to/file') as src, gzip.open('path/to/file.gz', 'wb') as dst:        
    dst.writelines(src)

回答4:

Use the gzip module:

import gzip
import os

in_file = "somefile.data"
in_data = open(in_file, "rb").read()
out_gz = "foo.gz"
gzf = gzip.open(out_gz, "wb")
gzf.write(in_data)
gzf.close()

# If you want to delete the original file after the gzip is done:
os.unlink(in_file)

Your error: OSError: [Errno 2] No such file or directory' is telling you that the file fullFilePath does not exist. If you still need to go that route, please make sure that file exists on your system and you are using an absolute path not relative.

回答5:

the documentation on this is actually insanely straightforward

Example of how to read a compressed file:

import gzip
f = gzip.open('file.txt.gz', 'rb')
file_content = f.read()
f.close()

Example of how to create a compressed GZIP file:

import gzip
content = "Lots of content here"
f = gzip.open('file.txt.gz', 'wb')
f.write(content)
f.close()

Example of how to GZIP compress an existing file:

import gzip
f_in = open('file.txt', 'rb')
f_out = gzip.open('file.txt.gz', 'wb')
f_out.writelines(f_in)
f_out.close()
f_in.close()

https://docs.python.org/2/library/gzip.html

That's the whole documentation . . .

回答6:

From the docs for Python3

Gzip an existing file

import gzip
import shutil
with open('file.txt', 'rb') as f_in:
    with gzip.open('file.txt.gz', 'wb') as f_out:
        shutil.copyfileobj(f_in, f_out)

# or because I hate nested with statements

import gzip
import shutil
from contextlib import ExitStack
with ExitStack() as stack:
    f_in = stack.enter_context(open('file.txt', 'rb'))
    f_out = stack.enter_context(gzip.open('file.txt.gz', 'wb'))
    shutil.copyfileobj(f_in, f_out)

Create a new gzip file:

import gzip
content = b"Lots of content here"
with gzip.open("file.txt.gz", "wb") as f:
    f.write(content)

Note the fact that content is turned into bytes

Another method for if you aren't creating content as a string/byte literal like the above example would be

import gzip
# get content as a string from somewhere else in the code
with gzip.open("file.txt.gz", "wb") as f:
    f.write(content.encode("utf-8"))

See this SO question for a discussion of other encoding methods.

回答7:

import gzip

def gzip_file(src_path, dst_path):
    with open(src_path, 'rb') as src, gzip.open(dst_path, 'wb') as dst:
        for chunk in iter(lambda: src.read(4096), b""):
            dst.write(chunk)

来源：https://stackoverflow.com/questions/8156707/gzip-a-file-in-python

标签

python

gzip

subprocess