Slack file downloader from export archive (2021)

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.
#        `python2 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:
                files = []
                if 'file' in content:
                    files.append(content['file'])
                if 'files' in content:
                    for file in content['files']:
                        files.append(file)
                
                for file in files:
                    if 'url_private_download' not in file:
                        continue

                    url = file['url_private_download']

                    try:
                        os.mkdir(os.path.join(channel, date))
                    except OSError:
                        pass

                    # Ensure that the files each have different names for each different id
                    filename = "%s - %s" % (file['id'], urlparse.urlparse(url).path.split('/')[-1])
                    download_path = os.path.join(channel, date, filename)
                    if os.path.isfile(download_path):
                        print('[-] Already downloaded %s -> %s' % (url, download_path))

                    else:
                        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)

Correctly downloads multiple files present in the content and takes improvement from edokan's fork to ensure files with the same name don't overwrite each other (for example when you paste an image into slack it gets image.png as a name).