summaryrefslogtreecommitdiff
path: root/contrib/caldav/calcurse-caldav.py
blob: 909d27b76974330da68d522d56c9c3a8611103ac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
#!/usr/bin/python3

import argparse
import base64
import configparser
import hashlib
import http.client
import os
import ssl
import subprocess
import sys
import textwrap
import xml.etree.ElementTree as etree

def die(msg):
    newmsg = ""
    for line in msg.splitlines():
        newmsg += textwrap.fill(line, 72) + '\n'
    msg = ""
    for line in newmsg.splitlines():
        msg += 'error: ' + line + '\n'
    sys.exit(msg.rstrip('\n'))

def die_atnode(msg, node):
    if verbose:
        msg += '\n\n'
        msg += 'The error occurred while processing the following XML node:\n'
        msg += etree.tostring(node).decode('utf-8')
    die(msg)

def calcurse_wipe():
    if verbose:
        print('Removing all local calcurse objects...')
    if dry_run:
        return
    subprocess.call([calcurse, '-F', '--filter-hash=XXX'])

def calcurse_import(icaldata):
    p = subprocess.Popen([calcurse, '-i', '-', '--list-imported', '-q'],
                         stdin=subprocess.PIPE, stdout=subprocess.PIPE)
    return p.communicate(icaldata.encode('utf-8'))[0].decode('utf-8').rstrip()

def calcurse_export(objhash):
    p = subprocess.Popen([calcurse, '-x', 'ical', '--export-uid',
                          '--filter-hash=' + objhash], stdout=subprocess.PIPE)
    return p.communicate()[0].decode('utf-8').rstrip()

def calcurse_hashset():
    p = subprocess.Popen([calcurse, '-G'], stdout=subprocess.PIPE)
    out = p.communicate()[0]

    hashes = set()
    for line in out.split(b'\n'):
        if not line:
            continue
        sha1 = hashlib.new('sha1')
        sha1.update(line)
        hashes.add(sha1.hexdigest())
    return hashes

def calcurse_remove(objhash):
    subprocess.call([calcurse, '-F', '--filter-hash=!' + objhash])

def calcurse_version():
    p = subprocess.Popen([calcurse, '--version'], stdout=subprocess.PIPE)
    tokens = p.communicate()[0].decode('utf-8').rstrip().split(" ")

    if len(tokens) < 2:
        return None
    if tokens[0] != 'Calcurse':
        return None
    tokens = tokens[1].split(".")
    if len(tokens) < 2:
        return None
    return int(tokens[0]) * 10 + int(tokens[1])

def get_auth_headers():
    if not username or not password:
        return {}
    user_password = ('%s:%s' % (username, password)).encode('ascii')
    user_password = base64.b64encode(user_password).decode('ascii')
    headers = { 'Authorization' : 'Basic %s' % user_password }
    return headers

def remote_query(cmd, path, additional_headers, body):
    headers = get_auth_headers()
    if cmd == 'PUT':
        headers['Content-Type'] = 'text/calendar; charset=utf-8'
    else:
        headers['Content-Type'] = 'application/xml; charset=utf-8'
    headers.update(additional_headers)

    if debug:
        print("> %s %s" % (cmd, path))
        print("> Headers: " + repr(headers))
        if body:
            for line in body.splitlines():
                print("> " + line)
        print()

    conn.request(cmd, path, headers=headers, body=body)

    resp = conn.getresponse()

    if not resp:
        return (None, None)

    headers = resp.getheaders()
    body = resp.read().decode('utf-8')

    if debug:
        print("< Headers: " + repr(headers))
        for line in body.splitlines():
            print("< " + line)
        print()

    if resp.status - (resp.status % 100) != 200:
        die(("The server at %s replied with HTTP status code %d (%s) " +
             "while trying to access %s.") %
            (hostname, resp.status, resp.reason, path))

    return (headers, body)

def get_hrefmap(conn, uid=None):
    if uid:
        propfilter = '<C:prop-filter name="UID">' +\
                     '<C:text-match collation="i;octet" >%s</C:text-match>' +\
                     '</C:prop-filter>' % (uid)
    else:
        propfilter = ''

    body = '<?xml version="1.0" encoding="utf-8" ?>' +\
           '<C:calendar-query xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">' +\
           '<D:prop><D:getetag /></D:prop><C:filter>' +\
           '<C:comp-filter name="VCALENDAR">' + propfilter + '</C:comp-filter>' +\
           '</C:filter></C:calendar-query>'
    headers, body = remote_query("REPORT", path, {}, body)
    if not headers:
        return {}
    root = etree.fromstring(body)

    hrefmap = {}
    for node in root.findall(".//D:response", namespaces=nsmap):
        etagnode = node.find("./D:propstat/D:prop/D:getetag", namespaces=nsmap)
        if etagnode is None:
            die_atnode('Missing ETag.', node)
        etag = etagnode.text.strip('"')

        hrefnode = node.find("./D:href", namespaces=nsmap)
        if hrefnode is None:
            die_atnode('Missing href.', node)
        href = hrefnode.text

        hrefmap[etag] = href

    return hrefmap

def remote_wipe(conn):
    if verbose:
        print('Removing all objects from the CalDAV server...')
    if dry_run:
        return

    remote_query("DELETE", path, {}, None)

def get_syncdb(fn):
    if not os.path.exists(fn):
        return {}

    if verbose:
        print('Loading synchronization database from ' + fn + '...')

    syncdb = {}
    with open(fn, 'r') as f:
        for line in f.readlines():
            etag, objhash = line.rstrip().split(' ')
            syncdb[etag] = objhash

    return syncdb

def save_syncdb(fn, syncdb):
    if verbose:
        print('Saving synchronization database to ' + fn + '...')
    if dry_run:
        return

    with open(fn, 'w') as f:
        for etag, objhash in syncdb.items():
            print("%s %s" % (etag, objhash), file=f)

def push_object(conn, objhash):
    body = calcurse_export(objhash)
    headers, body = remote_query("PUT", path + objhash + ".ics", {}, body)

    if not headers:
        return None

    etag = [header[1] for header in headers if header[0] == 'ETag'][0]
    while not etag:
        hrefmap = get_hrefmap(conn, objhash)
        if len(hrefmap.keys()) > 0:
            etag = hrefmap.keys()[0]
    etag = etag.strip('"')

    return etag

def remove_remote_object(conn, etag, href):
    headers = { 'If-Match' : '"' + etag + '"' }
    remote_query("DELETE", href, headers, None)

def push_objects(conn, syncdb, hrefmap):
    objhashes = calcurse_hashset()
    new = objhashes - set(syncdb.values())
    gone = set(syncdb.values()) - objhashes

    added = deleted = 0

    # Copy new objects to the server.
    for objhash in new:
        if verbose:
            print("Pushing new object %s to the server." % (objhash))
        if dry_run:
            continue

        etag = push_object(conn, objhash)
        syncdb[etag] = objhash
        added += 1

    # Remove locally deleted objects from the server.
    for objhash in gone:
        deletags = []
        for key, value in syncdb.items():
            if value == objhash:
                deletags.append(key)

        for etag in deletags:
            if not etag in hrefmap:
                continue
            href = hrefmap[etag]

            if verbose:
                print("Removing remote object %s (%s)." % (etag, href))
            if dry_run:
                continue

            remove_remote_object(conn, etag, href)
            syncdb.pop(etag, None)
            deleted += 1

    return (added, deleted)

def pull_objects(conn, syncdb, hrefmap):
    missing = set(hrefmap.keys()) - set(syncdb.keys())
    orphan = set(syncdb.keys()) - set(hrefmap.keys())

    # Download and import new objects from the server.
    body = '<?xml version="1.0" encoding="utf-8" ?>' +\
           '<C:calendar-multiget xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">' +\
           '<D:prop><D:getetag /><C:calendar-data /></D:prop>'
    for etag in missing:
        body += '<D:href>%s</D:href>' % (hrefmap[etag])
    body += '</C:calendar-multiget>'
    headers, body = remote_query("REPORT", path, {}, body)

    root = etree.fromstring(body)

    added = deleted = 0

    for node in root.findall(".//D:prop", namespaces=nsmap):
        etagnode = node.find("./D:getetag", namespaces=nsmap)
        if etagnode is None:
            die_atnode('Missing ETag.', node)
        etag = etagnode.text.strip('"')

        cdatanode = node.find("./C:calendar-data", namespaces=nsmap)
        if cdatanode is None:
            die_atnode('Missing calendar data.', node)
        cdata = cdatanode.text

        if verbose:
            print("Importing new object %s." % (etag))
        if dry_run:
            continue

        objhash = calcurse_import(cdata)
        syncdb[etag] = objhash
        added += 1

    # Delete objects that no longer exist on the server.
    for etag in orphan:
        objhash = syncdb[etag]

        if verbose:
            print("Removing local object %s." % (objhash))
        if dry_run:
            continue

        calcurse_remove(objhash)
        syncdb.pop(etag, None)
        deleted += 1

    return (added, deleted)

# Initialize the XML namespace map.
nsmap = { "D": "DAV:", "C": "urn:ietf:params:xml:ns:caldav" }

# Initialize default values.
configfn = os.path.expanduser("~/.calcurse/caldav/config")
lockfn = os.path.expanduser("~/.calcurse/caldav/lock")
syncdbfn = os.path.expanduser("~/.calcurse/caldav/sync.db")

# Parse command line arguments.
parser = argparse.ArgumentParser('calcurse-caldav')
parser.add_argument('--init', action='store', dest='init', default=None,
                    choices=['keep-remote', 'keep-local', 'two-way'],
                    help='initialize the sync database')
parser.add_argument('--config', action='store', dest='configfn',
                    default=configfn,
                    help='path to the calcurse-caldav configuration')
parser.add_argument('--lockfile', action='store', dest='lockfn',
                    default=lockfn,
                    help='path to the calcurse-caldav lock file')
parser.add_argument('--syncdb', action='store', dest='syncdbfn',
                    default=syncdbfn,
                    help='path to the calcurse-caldav sync DB')
parser.add_argument('-v', '--verbose', action='store_true', dest='verbose',
                    default=False,
                    help='print status messages to stdout')
parser.add_argument('--debug', action='store_true', dest='debug',
                    default=False, help='print debug messages to stdout')
args = parser.parse_args()

init = args.init is not None
configfn = args.configfn
lockfn = args.lockfn
syncdbfn = args.syncdbfn
verbose = args.verbose
debug = args.debug

# Read configuration.
config = configparser.RawConfigParser()
if verbose:
    print('Loading configuration from ' + configfn + '...')
try:
    config.readfp(open(configfn))
except FileNotFoundError as e:
    die('Configuration file not found: %s' % (configfn))

hostname = config.get('General', 'HostName')
path = '/' + config.get('General', 'Path').strip('/') + '/'

if config.has_option('General', 'InsecureSSL'):
    insecure_ssl = config.getboolean('General', 'InsecureSSL')
else:
    insecure_ssl = False

if config.has_option('General', 'Binary'):
    calcurse = config.get('General', 'Binary')
else:
    calcurse = 'calcurse'

if config.has_option('General', 'DryRun'):
    dry_run = config.getboolean('General', 'DryRun')
else:
    dry_run = True

if not verbose and config.has_option('General', 'Verbose'):
    verbose = config.getboolean('General', 'Verbose')

if not debug and config.has_option('General', 'Debug'):
    debug = config.getboolean('General', 'Debug')

if config.has_option('Auth', 'UserName'):
    username = config.get('Auth', 'UserName')
else:
    username = None

if config.has_option('Auth', 'Password'):
    password = config.get('Auth', 'Password')
else:
    password = None

# Show disclaimer when performing a dry run.
if dry_run:
    print('Dry run. Nothing is actually imported/exported.')
    print('Edit the configuration file and add "DryRun = No" to the [General] section')
    print('to enable synchronization.')

# Check whether the specified calcurse binary is executable and compatible.
ver = calcurse_version()
if ver is None:
    die('Invalid calcurse binary. Make sure that the file specified in ' +
        'the configuration is a valid and up-to-date calcurse binary.')
elif ver < 40:
    die('Incompatible calcurse binary detected. Version >=4.0.0 is required ' +
        'to synchronize with CalDAV servers.')

# Create lock file.
if os.path.exists(lockfn):
    die('Leftover lock file detected. If there is no other synchronization ' +
        'instance running, please remove the lock file manually and try ' +
        'again.')
open(lockfn, 'w')

try:
    # Connect to the server via HTTPs.
    if verbose:
        print('Connecting to ' + hostname + '...')
    if insecure_ssl:
        try:
            context = ssl._create_unverified_context()
            conn = http.client.HTTPSConnection(hostname, context=context)
        except AttributeError:
            # Python versions prior to 3.4 do not support
            # ssl._create_unverified_context(). However, these versions do not
            # seem to verify certificates by default so we can simply fall back
            # to http.client.HTTPSConnection().
            conn = http.client.HTTPSConnection(hostname)
    else:
        conn = http.client.HTTPSConnection(hostname)

    if init:
        # In initialization mode, start with an empty synchronization database.
        if (args.init == 'keep-remote'):
            calcurse_wipe()
        elif (args.init == 'keep-local'):
            remote_wipe(conn)
        syncdb = {}
    else:
        # Read the synchronization database.
        syncdb = get_syncdb(syncdbfn)

        if not syncdb:
            die('Sync database not found or empty. Please initialize the ' +
                'database first.\n\nSupported initialization modes are:\n' +
                '  --init=keep-remote Remove all local calcurse items and import remote objects\n' +
                '  --init=keep-local  Remove all remote objects and push local calcurse items\n' +
                '  --init=two-way     Copy local objects to the CalDAV server and vice versa')

    # Query the server and build a dictionary that maps ETags to paths on the
    # server.
    hrefmap = get_hrefmap(conn)

    # Retrieve new objects from the server, delete local items that no longer
    # exist on the server.
    local_new, local_del = pull_objects(conn, syncdb, hrefmap)

    # Push new objects to the server, remove items from the server if they no
    # longer exist locally.
    remote_new, remote_del = push_objects(conn, syncdb, hrefmap)

    # Write the synchronization database.
    save_syncdb(syncdbfn, syncdb)

    # Close the HTTPs connection.
    conn.close()
finally:
    # Remove lock file.
    os.remove(lockfn)

# Print a summary to stdout.
print("%d items imported, %d items removed locally." % (local_new, local_del))
print("%d items exported, %d items removed from the server." %
      (remote_new, remote_del))