ldapdb/models/base.py

   1 # -*- coding: utf-8 -*-
   2 #
   3 # django-ldapdb
   4 # Copyright (C) 2009-2010 Bolloré telecom
   5 # See AUTHORS file for a full list of contributors.
   6 #
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 #
  20
  21 import ldap
  22 import logging
  23
  24 import django.db.models
  25 from django.db.models import signals
  26
  27 import ldapdb
  28 from ldapdb.models.query import QuerySet
  29
  30 class ModelBase(django.db.models.base.ModelBase):
  31     """
  32     Metaclass for all LDAP models.
  33     """
  34     def __new__(cls, name, bases, attrs):
  35         super_new = super(ModelBase, cls).__new__
  36         new_class = super_new(cls, name, bases, attrs)
  37
  38         # patch manager to use our own QuerySet class
  39         if not new_class._meta.abstract:
  40             def get_query_set():
  41                 return QuerySet(new_class)
  42             new_class.objects.get_query_set = get_query_set
  43             new_class._default_manager.get_query_set = get_query_set
  44
  45         return new_class
  46
  47 class Model(django.db.models.base.Model):
  48     """
  49     Base class for all LDAP models.
  50     """
  51     __metaclass__ = ModelBase
  52
  53     dn = django.db.models.fields.CharField(max_length=200)
  54
  55     # meta-data
  56     base_dn = None
  57     object_classes = ['top']
  58
  59     def __init__(self, *args, **kwargs):
  60         super(Model, self).__init__(*args, **kwargs)
  61         self.saved_pk = self.pk
  62
  63     def build_rdn(self):
  64         """
  65         Build the Relative Distinguished Name for this entry.
  66         """
  67         bits = []
  68         for field in self._meta.local_fields:
  69             if field.primary_key:
  70                 bits.append("%s=%s" % (field.db_column, getattr(self, field.name)))
  71         if not len(bits):
  72             raise Exception("Could not build Distinguished Name")
  73         return '+'.join(bits)
  74
  75     def build_dn(self):
  76         """
  77         Build the Distinguished Name for this entry.
  78         """
  79         return "%s,%s" % (self.build_rdn(), self.base_dn)
  80         raise Exception("Could not build Distinguished Name")
  81
  82     def delete(self):
  83         """
  84         Delete this entry.
  85         """
  86         logging.debug("Deleting LDAP entry %s" % self.dn)
  87         ldapdb.connection.delete_s(self.dn)
  88         signals.post_delete.send(sender=self.__class__, instance=self)
  89
  90     def save(self):
  91         if not self.dn:
  92             # create a new entry
  93             record_exists = False
  94             entry = [('objectClass', self.object_classes)]
  95             new_dn = self.build_dn()
  96
  97             for field in self._meta.local_fields:
  98                 if not field.db_column:
  99                     continue
 100                 value = getattr(self, field.name)
 101                 if value:
 102                     entry.append((field.db_column, value))
 103
 104             logging.debug("Creating new LDAP entry %s" % new_dn)
 105             ldapdb.connection.add_s(new_dn, entry)
 106
 107             # update object
 108             self.dn = new_dn
 109
 110         else:
 111             # update an existing entry
 112             record_exists = True
 113             modlist = []
 114             orig = self.__class__.objects.get(pk=self.saved_pk)
 115             for field in self._meta.local_fields:
 116                 if not field.db_column:
 117                     continue
 118                 old_value = getattr(orig, field.name, None)
 119                 new_value = getattr(self, field.name, None)
 120                 if old_value != new_value:
 121                     if new_value:
 122                         modlist.append((ldap.MOD_REPLACE, field.db_column, new_value))
 123                     elif old_value:
 124                         modlist.append((ldap.MOD_DELETE, field.db_column, None))
 125
 126             if len(modlist):
 127                 # handle renaming
 128                 new_dn = self.build_dn()
 129                 if new_dn != self.dn:
 130                     logging.debug("Renaming LDAP entry %s to %s" % (self.dn, new_dn))
 131                     ldapdb.connection.rename_s(self.dn, self.build_rdn())
 132                     self.dn = new_dn
 133
 134                 logging.debug("Modifying existing LDAP entry %s" % self.dn)
 135                 ldapdb.connection.modify_s(self.dn, modlist)
 136             else:
 137                 logging.debug("No changes to be saved to LDAP entry %s" % self.dn)
 138
 139         # done
 140         self.saved_pk = self.pk
 141         signals.post_save.send(sender=self.__class__, instance=self, created=(not record_exists))
 142
 143     @classmethod
 144     def scoped(base_class, base_dn):
 145         """
 146         Returns a copy of the current class with a different base_dn.
 147         """
 148         import new
 149         import re
 150         suffix = re.sub('[=,]', '_', base_dn)
 151         name = "%s_%s" % (base_class.__name__, str(suffix))
 152         new_class = new.classobj(name, (base_class,), {'base_dn': base_dn, '__module__': base_class.__module__})
 153         return new_class
 154