Python: open zip file without extension of ".zip"

Question

I have a zip file called "main.zip". Inside that, I have another zip called "meta" which does not have the ".zip" extension. I want to open the "meta" zip file which contains lots of text files. But when I try to open the "meta" zip file, I get an error saying zipfile.BadZipfile: File is not a zip file. Below is my code:

zf = zipfile.ZipFile(inputZipFile, 'r')
print(zf.namelist())    # [u'meta']
zf2 = zipfile.ZipFile(zf.open('meta')) # throws error

I can't extract and open "meta" because I want to do this entirely in memory without writing to the disk.

My ultimate goal is to modify one of the text files and output a new zip.

Is it just the extension, or is `meta` perhaps corrupted? Compare opening zip files with and without the extension. What happens? — Prune, May 10 '17 at 18:01
@Prune I tried opening `meta` with .zip and it opened perfectly. And it's not currepted. I need to open it just as it is cuz I get the file from somewhere else. — Parth Bhoiwala, May 10 '17 at 18:04
@JaredGoguen I don't want to extract at all, for temp file I will have to extract it first. — Parth Bhoiwala, May 10 '17 at 18:04
The extension is not the issue here, you are passing a `ZipExtFile` to `zipfile.ZipFile`. — Jared Goguen, May 10 '17 at 18:10
@JaredGoguen Per the documentation that should work though. `ZipFile.open` produces a "binary file-like object" which is what `zipfile.Zipfile` expects. I proposed a workaround as an answer below. — Adam Smith, May 10 '17 at 18:18
@AdamSmith yup, just noticed that and was checking if an intermediate buffer would remedy the situation (as your answer uses) — Jared Goguen, May 10 '17 at 18:20
Whoops, this is a clearcut dupe with an exact copy of my answer by the venerable Martijn Pieters. I've hammered this to that. — Adam Smith, May 10 '17 at 18:32

score 3 · Accepted Answer · answered May 10 '17 at 18:16

3

If you're intent on doing this in memory, you need to create a file-like object to call zipfile.ZipFile on. Although ZipFile.open says that it does this, in practice I'm getting the same error you are.

What I've gotten to work is to read the binary with ZipFile.read and toss it into a io.BytesIO stream.

import io

with zipfile.ZipFile("main.zip") as zf:
    f2 = io.BytesIO(zf.read("meta"))
    with zipfile.ZipFile(f2) as zf2:
        # this is inside the inner zip file

answered May 10 '17 at 18:16

Adam Smith

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That worked like magic. Seriously, I have been trying something similar since hours with `StringIO` but it didn't work. `BytesIO` did the job. Thank you – Parth Bhoiwala May 10 '17 at 18:20
Hi @ParthBhoiwala ! i have the same situation as yours. Just that I just need to extract the files out of meta and thats it. I am not able to extract the files in meta. Can you help? – rohit nair Jun 16 '20 at 07:06

Python: open zip file without extension of ".zip"

1 Answers1