radicale/radicale/item/__init__.py
2019-06-17 04:13:24 +02:00

378 lines
14 KiB
Python

# This file is part of Radicale Server - Calendar Server
# Copyright © 2008 Nicolas Kandel
# Copyright © 2008 Pascal Halter
# Copyright © 2014 Jean-Marc Martins
# Copyright © 2008-2017 Guillaume Ayoub
# Copyright © 2017-2018 Unrud <unrud@outlook.com>
#
# This library is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Radicale. If not, see <http://www.gnu.org/licenses/>.
import math
import sys
from hashlib import md5
from random import getrandbits
import vobject
from radicale import pathutils
from radicale.item import filter as radicale_filter
def predict_tag_of_parent_collection(vobject_items):
if len(vobject_items) != 1:
return ""
if vobject_items[0].name == "VCALENDAR":
return "VCALENDAR"
if vobject_items[0].name in ("VCARD", "VLIST"):
return "VADDRESSBOOK"
return ""
def predict_tag_of_whole_collection(vobject_items, fallback_tag=None):
if vobject_items and vobject_items[0].name == "VCALENDAR":
return "VCALENDAR"
if vobject_items and vobject_items[0].name in ("VCARD", "VLIST"):
return "VADDRESSBOOK"
if not fallback_tag and not vobject_items:
# Maybe an empty address book
return "VADDRESSBOOK"
return fallback_tag
def check_and_sanitize_items(vobject_items, is_collection=False, tag=None):
"""Check vobject items for common errors and add missing UIDs.
``is_collection`` indicates that vobject_item contains unrelated
components.
The ``tag`` of the collection.
"""
if tag and tag not in ("VCALENDAR", "VADDRESSBOOK"):
raise ValueError("Unsupported collection tag: %r" % tag)
if not is_collection and len(vobject_items) != 1:
raise ValueError("Item contains %d components" % len(vobject_items))
if tag == "VCALENDAR":
if len(vobject_items) > 1:
raise RuntimeError("VCALENDAR collection contains %d "
"components" % len(vobject_items))
vobject_item = vobject_items[0]
if vobject_item.name != "VCALENDAR":
raise ValueError("Item type %r not supported in %r "
"collection" % (vobject_item.name, tag))
component_uids = set()
for component in vobject_item.components():
if component.name in ("VTODO", "VEVENT", "VJOURNAL"):
component_uid = get_uid(component)
if component_uid:
component_uids.add(component_uid)
component_name = None
object_uid = None
object_uid_set = False
for component in vobject_item.components():
# https://tools.ietf.org/html/rfc4791#section-4.1
if component.name == "VTIMEZONE":
continue
if component_name is None or is_collection:
component_name = component.name
elif component_name != component.name:
raise ValueError("Multiple component types in object: %r, %r" %
(component_name, component.name))
if component_name not in ("VTODO", "VEVENT", "VJOURNAL"):
continue
component_uid = get_uid(component)
if not object_uid_set or is_collection:
object_uid_set = True
object_uid = component_uid
if not component_uid:
if not is_collection:
raise ValueError("%s component without UID in object" %
component_name)
component_uid = find_available_uid(
component_uids.__contains__)
component_uids.add(component_uid)
if hasattr(component, "uid"):
component.uid.value = component_uid
else:
component.add("UID").value = component_uid
elif not object_uid or not component_uid:
raise ValueError("Multiple %s components without UID in "
"object" % component_name)
elif object_uid != component_uid:
raise ValueError(
"Multiple %s components with different UIDs in object: "
"%r, %r" % (component_name, object_uid, component_uid))
# vobject interprets recurrence rules on demand
try:
component.rruleset
except Exception as e:
raise ValueError("invalid recurrence rules in %s" %
component.name) from e
elif tag == "VADDRESSBOOK":
# https://tools.ietf.org/html/rfc6352#section-5.1
object_uids = set()
for vobject_item in vobject_items:
if vobject_item.name == "VCARD":
object_uid = get_uid(vobject_item)
if object_uid:
object_uids.add(object_uid)
for vobject_item in vobject_items:
if vobject_item.name == "VLIST":
# Custom format used by SOGo Connector to store lists of
# contacts
continue
if vobject_item.name != "VCARD":
raise ValueError("Item type %r not supported in %r "
"collection" % (vobject_item.name, tag))
object_uid = get_uid(vobject_item)
if not object_uid:
if not is_collection:
raise ValueError("%s object without UID" %
vobject_item.name)
object_uid = find_available_uid(object_uids.__contains__)
object_uids.add(object_uid)
if hasattr(vobject_item, "uid"):
vobject_item.uid.value = object_uid
else:
vobject_item.add("UID").value = object_uid
else:
for i in vobject_items:
raise ValueError("Item type %r not supported in %s collection" %
(i.name, repr(tag) if tag else "generic"))
def check_and_sanitize_props(props):
"""Check collection properties for common errors."""
tag = props.get("tag")
if tag and tag not in ("VCALENDAR", "VADDRESSBOOK"):
raise ValueError("Unsupported collection tag: %r" % tag)
def find_available_uid(exists_fn, suffix=""):
"""Generate a pseudo-random UID"""
# Prevent infinite loop
for _ in range(1000):
r = "%016x" % getrandbits(128)
name = "%s-%s-%s-%s-%s%s" % (
r[:8], r[8:12], r[12:16], r[16:20], r[20:], suffix)
if not exists_fn(name):
return name
# something is wrong with the PRNG
raise RuntimeError("No unique random sequence found")
def get_etag(text):
"""Etag from collection or item.
Encoded as quoted-string (see RFC 2616).
"""
etag = md5()
etag.update(text.encode("utf-8"))
return '"%s"' % etag.hexdigest()
def get_uid(vobject_component):
"""UID value of an item if defined."""
return (vobject_component.uid.value
if hasattr(vobject_component, "uid") else None)
def get_uid_from_object(vobject_item):
"""UID value of an calendar/addressbook object."""
if vobject_item.name == "VCALENDAR":
if hasattr(vobject_item, "vevent"):
return get_uid(vobject_item.vevent)
if hasattr(vobject_item, "vjournal"):
return get_uid(vobject_item.vjournal)
if hasattr(vobject_item, "vtodo"):
return get_uid(vobject_item.vtodo)
elif vobject_item.name == "VCARD":
return get_uid(vobject_item)
return None
def find_tag(vobject_item):
"""Find component name from ``vobject_item``."""
if vobject_item.name == "VCALENDAR":
for component in vobject_item.components():
if component.name != "VTIMEZONE":
return component.name or ""
return ""
def find_tag_and_time_range(vobject_item):
"""Find component name and enclosing time range from ``vobject item``.
Returns a tuple (``tag``, ``start``, ``end``) where ``tag`` is a string
and ``start`` and ``end`` are POSIX timestamps (as int).
This is intened to be used for matching against simplified prefilters.
"""
tag = find_tag(vobject_item)
if not tag:
return (
tag, radicale_filter.TIMESTAMP_MIN, radicale_filter.TIMESTAMP_MAX)
start = end = None
def range_fn(range_start, range_end, is_recurrence):
nonlocal start, end
if start is None or range_start < start:
start = range_start
if end is None or end < range_end:
end = range_end
return False
def infinity_fn(range_start):
nonlocal start, end
if start is None or range_start < start:
start = range_start
end = radicale_filter.DATETIME_MAX
return True
radicale_filter.visit_time_ranges(vobject_item, tag, range_fn, infinity_fn)
if start is None:
start = radicale_filter.DATETIME_MIN
if end is None:
end = radicale_filter.DATETIME_MAX
try:
return tag, math.floor(start.timestamp()), math.ceil(end.timestamp())
except ValueError as e:
if str(e) == ("offset must be a timedelta representing a whole "
"number of minutes") and sys.version_info < (3, 6):
raise RuntimeError("Unsupported in Python < 3.6: %s" % e) from e
raise
class Item:
def __init__(self, collection_path=None, collection=None,
vobject_item=None, href=None, last_modified=None, text=None,
etag=None, uid=None, name=None, component_name=None,
time_range=None):
"""Initialize an item.
``collection_path`` the path of the parent collection (optional if
``collection`` is set).
``collection`` the parent collection (optional).
``href`` the href of the item.
``last_modified`` the HTTP-datetime of when the item was modified.
``text`` the text representation of the item (optional if
``vobject_item`` is set).
``vobject_item`` the vobject item (optional if ``text`` is set).
``etag`` the etag of the item (optional). See ``get_etag``.
``uid`` the UID of the object (optional). See ``get_uid_from_object``.
``name`` the name of the item (optional). See ``vobject_item.name``.
``component_name`` the name of the primary component (optional).
See ``find_tag``.
``time_range`` the enclosing time range.
See ``find_tag_and_time_range``.
"""
if text is None and vobject_item is None:
raise ValueError(
"at least one of 'text' or 'vobject_item' must be set")
if collection_path is None:
if collection is None:
raise ValueError("at least one of 'collection_path' or "
"'collection' must be set")
collection_path = collection.path
assert collection_path == pathutils.strip_path(
pathutils.sanitize_path(collection_path))
self._collection_path = collection_path
self.collection = collection
self.href = href
self.last_modified = last_modified
self._text = text
self._vobject_item = vobject_item
self._etag = etag
self._uid = uid
self._name = name
self._component_name = component_name
self._time_range = time_range
def serialize(self):
if self._text is None:
try:
self._text = self.vobject_item.serialize()
except Exception as e:
raise RuntimeError("Failed to serialize item %r from %r: %s" %
(self.href, self._collection_path,
e)) from e
return self._text
@property
def vobject_item(self):
if self._vobject_item is None:
try:
self._vobject_item = vobject.readOne(self._text)
except Exception as e:
raise RuntimeError("Failed to parse item %r from %r: %s" %
(self.href, self._collection_path,
e)) from e
return self._vobject_item
@property
def etag(self):
"""Encoded as quoted-string (see RFC 2616)."""
if self._etag is None:
self._etag = get_etag(self.serialize())
return self._etag
@property
def uid(self):
if self._uid is None:
self._uid = get_uid_from_object(self.vobject_item)
return self._uid
@property
def name(self):
if self._name is None:
self._name = self.vobject_item.name or ""
return self._name
@property
def component_name(self):
if self._component_name is not None:
return self._component_name
return find_tag(self.vobject_item)
@property
def time_range(self):
if self._time_range is None:
self._component_name, *self._time_range = (
find_tag_and_time_range(self.vobject_item))
return self._time_range
def prepare(self):
"""Fill cache with values."""
orig_vobject_item = self._vobject_item
self.serialize()
self.etag
self.uid
self.name
self.time_range
self.component_name
self._vobject_item = orig_vobject_item