# -*- coding: utf-8 -*-
# 
# django-ldapdb
# Copyright (c) 2009-2011, Bolloré telecom
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# 
# See AUTHORS file for a full list of contributors.
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# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
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#     1. Redistributions of source code must retain the above copyright notice, 
#        this list of conditions and the following disclaimer.
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#        may be used to endorse or promote products derived from this software
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def is_ldap_model(model):
    # FIXME: there is probably a better check than testing 'base_dn'
	return hasattr(model, 'base_dn')

class Router(object):
    """
    A router to point database operations on LDAP models to the LDAP
    database.

    NOTE: if you have more than one LDAP database, you will need to
    write your own router.
    """

    def __init__(self):
        "Find the name of the LDAP database"
        from django.conf import settings
        self.ldap_alias = None
        for alias, settings_dict in settings.DATABASES.items():
            if settings_dict['ENGINE'] == 'ldapdb.backends.ldap':
                self.ldap_alias = alias
                break

    def allow_syncdb(self, db, model):
        "Do not create tables for LDAP models"
        if is_ldap_model(model):
            return db == self.ldap_alias
        return None

    def db_for_read(self, model, **hints):
        "Point all operations on LDAP models to the LDAP database"
        if is_ldap_model(model):
            return self.ldap_alias
        return None

    def db_for_write(self, model, **hints):
        "Point all operations on LDAP models to the LDAP database"
        if is_ldap_model(model):
            return self.ldap_alias
        return None