recursively Extract 7z files

nested_7z.py

import py7zlib
import os
import re


class SevenZFile(object):
    @classmethod
    def is_7zfile(cls, filepath):
        '''
        Class method: determine if file path points to a valid 7z archive.
        '''
        is7z = False
        fp = None
        try:
            fp = open(filepath, 'rb')
            archive = py7zlib.Archive7z(fp)
            n = len(archive.getnames())
            is7z = True
        finally:
            if fp:
                fp.close()
        return is7z

    def __init__(self, filepath):
        fp = open(filepath, 'rb')
        self.archive = py7zlib.Archive7z(fp)

    def extractall(self, path):
        for name in self.archive.getnames():
            outfilename = os.path.join(path, name)
            outdir = os.path.dirname(outfilename)
            if not os.path.exists(outdir):
                os.makedirs(outdir)
            outfile = open(outfilename, 'wb')
            outfile.write(self.archive.getmember(name).read())
            outfile.close()



def extract_nested_7z(zippedFile, toFolder):
    """ Extract a 7z file including any nested 7z files
        Delete the 7z file(s) after extraction
    """
    if not os.path.exists(zippedFile):
        return
    SevenZFile(zippedFile).extractall(toFolder)
    os.remove(zippedFile)
    for root, dirs, files in os.walk(toFolder):
        for filename in files:
            if re.search(r'\.7z$', filename):
                fileSpec = os.path.join(root, filename)
                extract_nested_7z(fileSpec, root)