Slack file downloader from export archive

slack-download.py

# -*- coding: utf-8 -*-
#
# Slack file downloader from export archive
#
# Requirements:
#     Python 2 (or Python3 if you can use six)
#
# How to use:
#     1. Log in as admin, export your chat logs, and download archive.
#     2. Unarchive archive to directory (ex. TeamName export Apr 24 2016)
#     3. Run this script.
#        `python slack-download.py "TeamName export Apr 24 2016"`


import json
import sys
import urllib
import urlparse
import os
import glob


def err(message):
    print('[-] '+message)
    os.exit(-1)


def main(export_path):
    if not os.path.isdir(export_path):
        err('Slack exported directory required.')

    os.chdir(export_path)

    for check_file in ('users.json', 'channels.json'):
        if not os.path.isfile(check_file):
            err('It seems that given directory is not an export directory.')

        for json_path in glob.glob('*/*.json'):
            channel, filename = os.path.split(json_path)
            date = filename.split('.')[0]

            with open(json_path, 'rb') as f:
                data = json.load(f)

            for content in data:
                if 'file' not in content:
                    continue

                if 'url_private_download' not in content['file']:
                    continue

                url = content['file']['url_private_download']
                id = content['file']['id']
                try:
                    os.mkdir(os.path.join(channel, date))
                except OSError:
                    pass

                filename = "%s - %s" % (id, urlparse.urlparse(url).path.split('/')[-1])
                download_path = os.path.join(channel, date, filename)

                if os.path.isfile(filename):
                	print('[*] Already downloaded %s' % url)
                	continue

                print('[+] Downloading %s -> %s' % (url, download_path))

                with open(download_path, 'wb') as f:
                    f.write(urllib.urlopen(url).read())


if __name__ == '__main__':
    if len(sys.argv) < 2:
        print('Usage: %s <Slack exported directory>' % sys.argv[0])
        sys.exit(-1)

    export_path = sys.argv[1]
    main(export_path)

Now does not try to download an already downloaded file and prefixes filenames with slack ids, so files with same name does not get overwritten.