app/django/db/backends/dummy/base.py
author Sverre Rabbelier <srabbelier@gmail.com>
Sat, 06 Dec 2008 14:23:53 +0000
changeset 679 77a286ff6667
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Introduce dynamic scope_path regexps Instead of relying on scope_path's being "one slash deep", we should instead allow for either: 1. scope_paths that have a pre-defined depth 2. scope_paths that can be arbitrarily deep We achieve 1 by setting an entities scope_logic to another logic module. We then recursively call getScopeDepth until we get to the topmost entity (that is, an unscoped entity). A little different is the solution to 2, since some entities can have an arbitrarily deep scope (such as Documents), we need to have some way of signaling this to getScopePattern. A clean solution is to return None, rather than a number. If None is returned, the SCOPE_PATH_ARG_PATTERN is returned as regexp instead, which will match an arbitrarily deeply nested scope. The solution for 2 requires that we return None somewhere in the scope_logic chain, the most straight forward method to do so is to override getScopeDepth anywhere such a scope is needed and make it return None. A more elegant solution however, is to set the scope_logic to that module in all entities that require it. Patch by: Sverre Rabbelier

"""
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, *args, **kwargs):
        super(DatabaseWrapper, self).__init__(*args, **kwargs)

        self.features = BaseDatabaseFeatures()
        self.ops = DatabaseOperations()
        self.client = DatabaseClient()
        self.creation = BaseDatabaseCreation(self)
        self.introspection = DatabaseIntrospection(self)
        self.validation = BaseDatabaseValidation()

    def close(self):
        pass