def _unpack(archive_file):
"""Unpacks and extracts files from an archive
This function will unpack and extra files from the file archive_file. It
will return the directory to which the files were unpacked.
An AttributeError is raised when the archive is not supported (when the
name does not end with '.zip' or '.tar.gz')
Returns string.
"""
logger.info("Unpacking archive '{0}'".format(archive_file))
if archive_file.endswith('.zip'):
archive = ZipFile(archive_file)
rootdir = archive.namelist()[0]
elif archive.endswith('.tar.gz'):
archive = tarfile.open(archive_file)
rootdir = archive.getnames()[0]
else:
raise AttributeError("Unsupported archive. Can't unpack.")
logger.info("Archive root folder is '{0}'".format(rootdir))
try:
shutil.rmtree(rootdir)
except OSError:
pass
logger.info("Extracting to '{0}'".format(rootdir))
archive.extractall()
archive.close()
return rootdir
