#SpiderOak zipstream module ##THIS IS A GITHUB MIRROR ONLY

###This library was created by SpiderOak, Inc. and is released under the GPLv3.

• https://spideroak.com/
• codefeedback@spideroak.com

zipstream.py is a zip archive generator based on zipfile.py. It was created to generate a zip file on-the-fly for download in a web.py (http://webpy.org/) application. This is beneficial for when you want to provide a downloadable archive of a large collection of regular files, which would be infeasible to generate the archive prior to downloading.

The archive is generated as an iterator of strings, which, when joined, form the zip archive. For example, the following code snippet would write a zip archive containing files from 'path' to a normal file:

zf = open('zipfile.zip', 'wb')
for data in ZipStream(path):
    zf.write(data)
zf.close()

Since recent versions of web.py support returning iterators of strings to be sent to the browser, to download a dynamically generated archive, you could use something like this snippet:

def GET(self):
    path = '/path/to/dir/of/files'
    zip_filename = 'files.zip'
    web.header('Content-type' , 'application/zip')
    web.header('Content-Disposition', 'attachment; filename="%s"' % (
        zip_filename,))
    return ZipStream(path)

If the zlib module is available, ZipStream can generate compressed zip archives.

Contact the SpiderOak team at spideroak_tools@spideroak.com

And be sure to back up your files! http://www.spideroak.com

##ZipStream works with HUGE files too!

Generate 6 gigs of random data

ionadmin@onfire:/results/zip$ dd if=/dev/urandom of=file.blob bs=1048576 count=6000

Get the checksum of the generated file

ionadmin@onfire:/results/zip$ md5sum file.blob
11ef7625569f44977789caa785b5f112  file.blob

Now compress it using zipstream

from zipstream import ZipStream
toZip = "/results/zip/file.blob"
zf = open('zipfile.zip', 'wb')
for data in ZipStream(toZip):
    zf.write(data)
zf.close()

Check the output zipfile checksum

ionadmin@onfire:/results/zip/output$ md5sum zipfile.zip
405437edcb0c81d7639e01f8f1e50417  zipfile.zip

Unzip the zipped file ionadmin@onfire:/results/zip/output$ unzip zipfile.zip

The resulting file checksum

ionadmin@onfire:/results/zip/output$ md5sum file.blob
11ef7625569f44977789caa785b5f112  file.blob

So ZipStream is a great solution if you need to zip large files with Python 2.6.5.

zipfile with Python 2.6.5 is broken for large files - http://bugs.python.org/issue8571

Python 2.6.5 is part of Ubuntu 10.04. So this ZipStream is a great solution to zip large files with Python 2.6.5!