calypso/xmlutils.py

   1 # -*- coding: utf-8 -*-
   2 #
   3 # This file is part of Calypso Server - Calendar Server
   4 # Copyright © 2008-2011 Guillaume Ayoub
   5 # Copyright © 2008 Nicolas Kandel
   6 # Copyright © 2008 Pascal Halter
   7 #
   8 # This library is free software: you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation, either version 3 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # This library is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with Calypso.  If not, see <http://www.gnu.org/licenses/>.
  20
  21 """
  22 XML and iCal requests manager.
  23
  24 Note that all these functions need to receive unicode objects for full
  25 iCal requests (PUT) and string objects with charset correctly defined
  26 in them for XML requests (all but PUT).
  27
  28 """
  29
  30 import xml.etree.ElementTree as ET
  31 import time
  32 import dateutil
  33 import dateutil.parser
  34 import dateutil.rrule
  35 import dateutil.tz
  36 import datetime
  37
  38 import urllib
  39
  40 from calypso import client, config, ical
  41
  42
  43 NAMESPACES = {
  44     "C": "urn:ietf:params:xml:ns:caldav",
  45     "D": "DAV:",
  46     "CS": "http://calendarserver.org/ns/"}
  47
  48
  49 def _tag(short_name, local):
  50     """Get XML Clark notation {uri(``short_name``)}``local``."""
  51     return "{%s}%s" % (NAMESPACES[short_name], local)
  52
  53
  54 def _response(code):
  55     """Return full W3C names from HTTP status codes."""
  56     return "HTTP/1.1 %i %s" % (code, client.responses[code])
  57
  58
  59 def name_from_path(path):
  60     """Return Calypso item name from ``path``."""
  61     path_parts = path.strip("/").split("/")
  62     return urllib.unquote(path_parts[-1]) if len(path_parts) > 2 else None
  63
  64 def delete(path, calendar):
  65     """Read and answer DELETE requests.
  66
  67     Read rfc4918-9.6 for info.
  68
  69     """
  70     # Reading request
  71     print "delete name %s" % name_from_path(path)
  72     calendar.remove(name_from_path(path))
  73
  74     # Writing answer
  75     multistatus = ET.Element(_tag("D", "multistatus"))
  76     response = ET.Element(_tag("D", "response"))
  77     multistatus.append(response)
  78
  79     href = ET.Element(_tag("D", "href"))
  80     href.text = path
  81     response.append(href)
  82
  83     status = ET.Element(_tag("D", "status"))
  84     status.text = _response(200)
  85     response.append(status)
  86
  87     print "Deleted\n"
  88     return ET.tostring(multistatus, config.get("encoding", "request"))
  89
  90
  91 def propfind(path, xml_request, calendar, depth):
  92     """Read and answer PROPFIND requests.
  93
  94     Read rfc4918-9.1 for info.
  95
  96     """
  97     # Reading request
  98     root = ET.fromstring(xml_request)
  99
 100     prop_element = root.find(_tag("D", "prop"))
 101     prop_list = prop_element.getchildren()
 102     props = [prop.tag for prop in prop_list]
 103
 104     # Writing answer
 105     multistatus = ET.Element(_tag("D", "multistatus"))
 106
 107     if calendar:
 108         if depth == "0":
 109             items = [calendar]
 110         else:
 111             # depth is 1, infinity or not specified
 112             # we limit ourselves to depth == 1
 113             items = [calendar] + calendar.items
 114     else:
 115         items = []
 116
 117     for item in items:
 118         is_calendar = isinstance(item, ical.Calendar)
 119
 120         response = ET.Element(_tag("D", "response"))
 121         multistatus.append(response)
 122
 123         href = ET.Element(_tag("D", "href"))
 124         href.text = path if is_calendar else path + item.name
 125         response.append(href)
 126
 127         propstat = ET.Element(_tag("D", "propstat"))
 128         response.append(propstat)
 129
 130         prop = ET.Element(_tag("D", "prop"))
 131         propstat.append(prop)
 132
 133         for tag in props:
 134             element = ET.Element(tag)
 135             if tag == _tag("D", "resourcetype"):
 136                 tag = ET.Element(_tag("C", "calendar"))
 137                 element.append(tag)
 138                 tag = ET.Element(_tag("D", "collection"))
 139                 element.append(tag)
 140             elif tag == _tag("D", "owner"):
 141                 element.text = calendar.owner
 142             elif tag == _tag("D", "getcontenttype"):
 143                 if item.tag == 'VCARD':
 144                     element.text = "text/vcard"
 145                 else:
 146                     element.text = "text/calendar"
 147             elif tag == _tag("CS", "getctag") and is_calendar:
 148                 element.text = item.ctag
 149             elif tag == _tag("D", "getetag"):
 150                 element.text = item.etag
 151             elif tag == _tag("D", "displayname"):
 152                 element.text = calendar.name
 153             elif tag == _tag("D", "principal-URL"):
 154                 # TODO: use a real principal URL, read rfc3744-4.2 for info
 155                 tag = ET.Element(_tag("D", "href"))
 156                 tag.text = path
 157                 element.append(tag)
 158             elif tag in (
 159                 _tag("D", "principal-collection-set"),
 160                 _tag("C", "calendar-user-address-set"),
 161                 _tag("C", "calendar-home-set")):
 162                 tag = ET.Element(_tag("D", "href"))
 163                 tag.text = path
 164                 element.append(tag)
 165             elif tag == _tag("C", "supported-calendar-component-set"):
 166                 comp = ET.Element(_tag("C", "comp"))
 167                 comp.set("name", "VTODO") # pylint: disable=W0511
 168                 element.append(comp)
 169                 comp = ET.Element(_tag("C", "comp"))
 170                 comp.set("name", "VEVENT")
 171                 element.append(comp)
 172             elif tag == _tag("D", "current-user-privilege-set"):
 173                 privilege = ET.Element(_tag("D", "privilege"))
 174                 privilege.append(ET.Element(_tag("D", "all")))
 175                 element.append(privilege)
 176             elif tag == _tag("D", "getcontentlength"):
 177                 element.text = item.length
 178             elif tag == _tag("D", "getlastmodified"):
 179                 element.text = time.strftime("%a, %d %b %Y %H:%M:%S +0000", item.last_modified)
 180             prop.append(element)
 181
 182         status = ET.Element(_tag("D", "status"))
 183         status.text = _response(200)
 184         propstat.append(status)
 185
 186     return ET.tostring(multistatus, config.get("encoding", "request"))
 187
 188
 189 def put(path, ical_request, calendar):
 190     """Read PUT requests."""
 191     name = name_from_path(path)
 192     if name in (item.name for item in calendar.items):
 193         # PUT is modifying an existing item
 194         calendar.replace(name, ical_request)
 195     else:
 196         # PUT is adding a new item
 197         calendar.append(name, ical_request)
 198
 199
 200 def match_filter_element(vobject, fe):
 201     if fe.tag == _tag("C", "comp-filter"):
 202         comp = fe.get("name")
 203         if comp:
 204             if comp == vobject.name:
 205                 hassub = False
 206                 submatch = False
 207                 for fc in fe.getchildren():
 208                     if match_filter_element(vobject, fc):
 209                         submatch = True
 210                         break
 211                     for vc in vobject.getChildren():
 212                         hassub = True
 213                         if match_filter_element (vc, fc):
 214                             submatch = True
 215                             break
 216                     if submatch:
 217                         break
 218                 if not hassub or submatch:
 219                     return True
 220         return False
 221     elif fe.tag == _tag("C", "time-range"):
 222         try:
 223             rruleset = vobject.rruleset
 224         except AttributeError:
 225             return False
 226         start = fe.get("start")
 227         end = fe.get("end")
 228         if rruleset is None:
 229             rruleset = dateutil.rrule.rruleset()
 230             dtstart = vobject.dtstart.value
 231             try:
 232                 dtstart = datetime.datetime.combine(dtstart, datetime.time())
 233             except Exception:
 234                 0
 235             if dtstart.tzinfo is None:
 236                 dtstart = dtstart.replace(tzinfo = dateutil.tz.tzlocal())
 237             rruleset.rdate(dtstart)
 238         start_datetime = dateutil.parser.parse(start)
 239         if start_datetime.tzinfo is None:
 240             start_datetime = start_datetime.replace(tzinfo = dateutil.tz.tzlocal())
 241         end_datetime = dateutil.parser.parse(end)
 242         if end_datetime.tzinfo is None:
 243             end_datetime = end_datetime.replace(tzinfo = dateutil.tz.tzlocal())
 244         try:
 245             if rruleset.between(start_datetime, end_datetime, True):
 246                 return True
 247         except TypeError:
 248             start_datetime = start_datetime.replace(tzinfo = None)
 249             end_datetime = end_datetime.replace(tzinfo = None)
 250             try:
 251                 if rruleset.between(start_datetime, end_datetime, True):
 252                     return True
 253             except TypeError:
 254                 return True
 255         return False
 256     return True
 257
 258 def match_filter(item, filter):
 259     if filter is None:
 260         return True
 261     if filter.tag != _tag("C", "filter"):
 262         return True
 263     for fe in filter.getchildren():
 264         if match_filter_element(item.object, fe):
 265             return True
 266
 267 def report(path, xml_request, calendar):
 268     """Read and answer REPORT requests.
 269
 270     Read rfc3253-3.6 for info.
 271
 272     """
 273     # Reading request
 274     root = ET.fromstring(xml_request)
 275
 276     prop_element = root.find(_tag("D", "prop"))
 277     prop_list = prop_element.getchildren()
 278     props = [prop.tag for prop in prop_list]
 279
 280     filter_element = root.find(_tag("C", "filter"))
 281
 282     if calendar:
 283         if root.tag == _tag("C", "calendar-multiget"):
 284             # Read rfc4791-7.9 for info
 285             hreferences = set((href_element.text for href_element
 286                                in root.findall(_tag("D", "href"))))
 287         else:
 288             hreferences = (path,)
 289     else:
 290         hreferences = ()
 291
 292     # Writing answer
 293     multistatus = ET.Element(_tag("D", "multistatus"))
 294
 295     for hreference in hreferences:
 296         # Check if the reference is an item or a calendar
 297         name = name_from_path(hreference)
 298         if name:
 299             # Reference is an item
 300             path = "/".join(hreference.split("/")[:-1]) + "/"
 301             items = (item for item in calendar.items if item.name == name)
 302         else:
 303             # Reference is a calendar
 304             path = hreference
 305             items = calendar.items
 306
 307
 308         for item in items:
 309             if not match_filter(item, filter_element):
 310                 continue
 311
 312             response = ET.Element(_tag("D", "response"))
 313             multistatus.append(response)
 314
 315             href = ET.Element(_tag("D", "href"))
 316             href.text = path + item.name
 317             response.append(href)
 318
 319             propstat = ET.Element(_tag("D", "propstat"))
 320             response.append(propstat)
 321
 322             prop = ET.Element(_tag("D", "prop"))
 323             propstat.append(prop)
 324
 325             for tag in props:
 326                 element = ET.Element(tag)
 327                 if tag == _tag("D", "getetag"):
 328                     element.text = item.etag
 329                 elif tag == _tag("C", "calendar-data"):
 330                     element.text = item.text
 331                 prop.append(element)
 332
 333             status = ET.Element(_tag("D", "status"))
 334             status.text = _response(200)
 335             propstat.append(status)
 336
 337     reply = ET.tostring(multistatus, config.get("encoding", "request"))
 338
 339     return reply