"""

Dummy database backend for Django.

Django uses this if the database ENGINE setting is empty (None or empty string).

Each of these API functions, except connection.close(), raises

ImproperlyConfigured.

"""

from django.core.exceptions import ImproperlyConfigured

from django.db.backends import *

from django.db.backends.creation import BaseDatabaseCreation

def complain(*args, **kwargs):

    raise ImproperlyConfigured("You haven't set the database ENGINE setting yet.")

def ignore(*args, **kwargs):

    pass

class DatabaseError(Exception):

    pass

class IntegrityError(DatabaseError):

    pass

class DatabaseOperations(BaseDatabaseOperations):

    quote_name = complain

class DatabaseClient(BaseDatabaseClient):

    runshell = complain

class DatabaseIntrospection(BaseDatabaseIntrospection):

    get_table_list = complain

    get_table_description = complain

    get_relations = complain

    get_indexes = complain

class DatabaseWrapper(object):

    operators = {}

    cursor = complain

    _commit = complain

    _rollback = ignore

    def __init__(self, settings_dict, alias, *args, **kwargs):

        self.features = BaseDatabaseFeatures()

        self.ops = DatabaseOperations()

        self.client = DatabaseClient(self)

        self.creation = BaseDatabaseCreation(self)

        self.introspection = DatabaseIntrospection(self)

        self.validation = BaseDatabaseValidation(self)

        self.settings_dict = settings_dict

        self.alias = alias

    def close(self):

        pass