Generate json with changes in WebDAV folder (or other folder)

main.py

#!/usr/bin/env python

####################
# Generate json with changes in WebDAV folder (or other folder) 
#
# used some code from: http://thomassileo.com/blog/2013/12/12/tracking-changes-in-directories-with-python/
# tested with python 2.7
#
# edit crontab: sudo crontab -e
#      example: */1 * * * * /path-to-script/main.py
# check permissions /var/www/html/index.html
####################

import os
import hashlib
import json

def json_load(fname):
    with open(fname, mode='r') as f:
        data = json.load(f)
    return data


def json_save(fname, data):
    with open(fname, mode='w') as f:
        json.dump(data, f)
 

def compute_dir_index(path):
    files = []
    subdirs = []

    for root, dirs, filenames in os.walk(path):
        for subdir in dirs:
            subdirs.append(os.path.relpath(os.path.join(root,subdir), path))
   
        for f in filenames:
            files.append(os.path.relpath(os.path.join(root, f), path))

    index = {}
    for f in files:
        index[f] = os.path.getmtime(os.path.join(path, files[0]))

    return dict(files=files, subdirs=subdirs, index=index)


def compute_diff(dir_base, dir_cmp):
    data = {}
    data['deleted'] = list(set(dir_cmp['files']) - set(dir_base['files']))
    data['created'] = list(set(dir_base['files']) - set(dir_cmp['files']))
    data['updated'] = []
    data['deleted_dirs'] = list(set(dir_cmp['subdirs']) - set(dir_base['subdirs']))

    for f in set(dir_cmp['files']).intersection(set(dir_base['files'])):
        if dir_base['index'][f] != dir_cmp['index'][f]:
            data['updated'].append(f)

    return data


if __name__ == "__main__":
    path = '/var/www/webdav/'
    fname = '/var/www/html/index.html'

    diff = compute_dir_index(path)

    if os.path.exists(fname):
        if os.path.isfile(fname):
            diff2 = json_load(fname)
            from pprint import pprint
            pprint(compute_diff(diff, diff2))
            json_save(fname, diff)
        else:
            raise ValueError("%s isn't a file!" % fname)
    else:
        json_save(fname, diff)