ldapdb/backends/ldap/compiler.py

   1 # -*- coding: utf-8 -*-
   2 #
   3 # django-ldapdb
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  17 #        documentation and/or other materials provided with the distribution.
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  20 #        may be used to endorse or promote products derived from this software
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  24 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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  32 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33 #
  34
  35 from django.db.models.sql import compiler
  36
  37 import ldap
  38
  39 class SQLCompiler(object):
  40     def __init__(self, query, connection, using):
  41         self.query = query
  42         self.connection = connection
  43         self.using = using
  44
  45     def results_iter(self):
  46         if self.query.select_fields:
  47             fields = self.query.select_fields
  48         else:
  49             fields = self.query.model._meta.fields
  50
  51         attrlist = [ x.db_column for x in fields if x.db_column ]
  52
  53         try:
  54             vals = self.connection.search_s(
  55                 self.query.model.base_dn,
  56                 self.query.model.search_scope,
  57                 filterstr=self.query._ldap_filter(),
  58                 attrlist=attrlist,
  59             )
  60         except ldap.NO_SUCH_OBJECT:
  61             return
  62
  63         # perform sorting
  64         if self.query.extra_order_by:
  65             ordering = self.query.extra_order_by
  66         elif not self.query.default_ordering:
  67             ordering = self.query.order_by
  68         else:
  69             ordering = self.query.order_by or self.query.model._meta.ordering
  70         def cmpvals(x, y):
  71             for fieldname in ordering:
  72                 if fieldname.startswith('-'):
  73                     fieldname = fieldname[1:]
  74                     negate = True
  75                 else:
  76                     negate = False
  77                 field = self.query.model._meta.get_field(fieldname)
  78                 attr_x = field.from_ldap(x[1].get(field.db_column, []), connection=self.connection)
  79                 attr_y = field.from_ldap(y[1].get(field.db_column, []), connection=self.connection)
  80                 # perform case insensitive comparison
  81                 if hasattr(attr_x, 'lower'):
  82                     attr_x = attr_x.lower()
  83                 if hasattr(attr_y, 'lower'):
  84                     attr_y = attr_y.lower()
  85                 val = negate and cmp(attr_y, attr_x) or cmp(attr_x, attr_y)
  86                 if val:
  87                     return val
  88             return 0
  89         vals = sorted(vals, cmp=cmpvals)
  90
  91         # process results
  92         pos = 0
  93         for dn, attrs in vals:
  94             # FIXME : This is not optimal, we retrieve more results than we need
  95             # but there is probably no other options as we can't perform ordering
  96             # server side.
  97             if (self.query.low_mark and pos < self.query.low_mark) or \
  98                (self.query.high_mark is not None and pos >= self.query.high_mark):
  99                 pos += 1
 100                 continue
 101             row = []
 102             for field in iter(fields):
 103                 if field.attname == 'dn':
 104                     row.append(dn)
 105                 elif hasattr(field, 'from_ldap'):
 106                     row.append(field.from_ldap(attrs.get(field.db_column, []), connection=self.connection))
 107                 else:
 108                     row.append(None)
 109             yield row
 110             pos += 1
 111
 112 class SQLInsertCompiler(compiler.SQLInsertCompiler, SQLCompiler):
 113     pass
 114
 115 class SQLDeleteCompiler(compiler.SQLDeleteCompiler, SQLCompiler):
 116     pass
 117
 118 class SQLUpdateCompiler(compiler.SQLUpdateCompiler, SQLCompiler):
 119     pass
 120
 121 class SQLAggregateCompiler(compiler.SQLAggregateCompiler, SQLCompiler):
 122     pass
 123
 124 class SQLDateCompiler(compiler.SQLDateCompiler, SQLCompiler):
 125     pass
 126