unzipping file results in "BadZipFile: File is not a zip file"

sharjeel picture sharjeel · Jun 21, 2010 · Viewed 96.8k times · Source

I have two zip files, both of them open well with Windows Explorer and 7-zip.

However when i open them with Python's zipfile module [ zipfile.ZipFile("filex.zip") ], one of them gets opened but the other one gives error "BadZipfile: File is not a zip file".

I've made sure that the latter one is a valid Zip File by opening it with 7-Zip and looking at its properties (says 7Zip.ZIP). When I open the file with a text editor, the first two characters are "PK", showing that it is indeed a zip file.

I'm using Python 2.5 and really don't have any clue how to go about for this. I've tried it both with Windows as well as Ubuntu and problem exists on both platforms.

Update: Traceback from Python 2.5.4 on Windows:

Traceback (most recent call last):
File "<module1>", line 5, in <module>
    zipfile.ZipFile("c:/temp/test.zip")
File "C:\Python25\lib\zipfile.py", line 346, in init
    self._GetContents()
File "C:\Python25\lib\zipfile.py", line 366, in _GetContents
    self._RealGetContents()
File "C:\Python25\lib\zipfile.py", line 378, in _RealGetContents
    raise BadZipfile, "File is not a zip file"
BadZipfile: File is not a zip file

Basically when the _EndRecData function is called for getting data from End of Central Directory" record, the comment length checkout fails [ endrec[7] == len(comment) ].

The values of locals in the _EndRecData function are as following:

 END_BLOCK: 4096,
 comment: '\x00',
 data: '\xd6\xf6\x03\x00\x88,N8?<e\xf0q\xa8\x1cwK\x87\x0c(\x82a\xee\xc61N\'1qN\x0b\x16K-\x9d\xd57w\x0f\xa31n\xf3dN\x9e\xb1s\xffu\xd1\.....', (truncated)
 endrec: ['PK\x05\x06', 0, 0, 4, 4, 268, 199515, 0],
 filesize: 199806L,
 fpin: <open file 'c:/temp/test.zip', mode 'rb' at 0x045D4F98>,
 start: 4073

Answer

astronautlevel picture astronautlevel · Jul 8, 2012

files named file can confuse python - try naming it something else. if it STILL wont work, try this code:

def fixBadZipfile(zipFile):  
 f = open(zipFile, 'r+b')  
 data = f.read()  
 pos = data.find('\x50\x4b\x05\x06') # End of central directory signature  
 if (pos > 0):  
     self._log("Trancating file at location " + str(pos + 22)+ ".")  
     f.seek(pos + 22)   # size of 'ZIP end of central directory record' 
     f.truncate()  
     f.close()  
 else:  
     # raise error, file is truncated