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
"""
PostgreSQL database backend for Django.
Requires psycopg 1: http://initd.org/projects/psycopg1
"""
from django.db.backends import *
from django.db.backends.postgresql.client import DatabaseClient
from django.db.backends.postgresql.creation import DatabaseCreation
from django.db.backends.postgresql.introspection import DatabaseIntrospection
from django.db.backends.postgresql.operations import DatabaseOperations
from django.db.backends.postgresql.version import get_version
from django.utils.encoding import smart_str, smart_unicode
try:
import psycopg as Database
except ImportError, e:
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured("Error loading psycopg module: %s" % e)
DatabaseError = Database.DatabaseError
IntegrityError = Database.IntegrityError
class UnicodeCursorWrapper(object):
"""
A thin wrapper around psycopg cursors that allows them to accept Unicode
strings as params.
This is necessary because psycopg doesn't apply any DB quoting to
parameters that are Unicode strings. If a param is Unicode, this will
convert it to a bytestring using database client's encoding before passing
it to psycopg.
All results retrieved from the database are converted into Unicode strings
before being returned to the caller.
"""
def __init__(self, cursor, charset):
self.cursor = cursor
self.charset = charset
def format_params(self, params):
if isinstance(params, dict):
result = {}
charset = self.charset
for key, value in params.items():
result[smart_str(key, charset)] = smart_str(value, charset)
return result
else:
return tuple([smart_str(p, self.charset, True) for p in params])
def execute(self, sql, params=()):
return self.cursor.execute(smart_str(sql, self.charset), self.format_params(params))
def executemany(self, sql, param_list):
new_param_list = [self.format_params(params) for params in param_list]
return self.cursor.executemany(sql, new_param_list)
def __getattr__(self, attr):
if attr in self.__dict__:
return self.__dict__[attr]
else:
return getattr(self.cursor, attr)
def __iter__(self):
return iter(self.cursor)
class DatabaseFeatures(BaseDatabaseFeatures):
uses_savepoints = True
class DatabaseWrapper(BaseDatabaseWrapper):
operators = {
'exact': '= %s',
'iexact': '= UPPER(%s)',
'contains': 'LIKE %s',
'icontains': 'LIKE UPPER(%s)',
'regex': '~ %s',
'iregex': '~* %s',
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': 'LIKE %s',
'endswith': 'LIKE %s',
'istartswith': 'LIKE UPPER(%s)',
'iendswith': 'LIKE UPPER(%s)',
}
def __init__(self, *args, **kwargs):
super(DatabaseWrapper, self).__init__(*args, **kwargs)
self.features = DatabaseFeatures()
self.ops = DatabaseOperations()
self.client = DatabaseClient()
self.creation = DatabaseCreation(self)
self.introspection = DatabaseIntrospection(self)
self.validation = BaseDatabaseValidation()
def _cursor(self, settings):
set_tz = False
if self.connection is None:
set_tz = True
if settings.DATABASE_NAME == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured("You need to specify DATABASE_NAME in your Django settings file.")
conn_string = "dbname=%s" % settings.DATABASE_NAME
if settings.DATABASE_USER:
conn_string = "user=%s %s" % (settings.DATABASE_USER, conn_string)
if settings.DATABASE_PASSWORD:
conn_string += " password='%s'" % settings.DATABASE_PASSWORD
if settings.DATABASE_HOST:
conn_string += " host=%s" % settings.DATABASE_HOST
if settings.DATABASE_PORT:
conn_string += " port=%s" % settings.DATABASE_PORT
self.connection = Database.connect(conn_string, **self.options)
self.connection.set_isolation_level(1) # make transactions transparent to all cursors
cursor = self.connection.cursor()
if set_tz:
cursor.execute("SET TIME ZONE %s", [settings.TIME_ZONE])
if not hasattr(self, '_version'):
self.__class__._version = get_version(cursor)
if self._version < (8, 0):
# No savepoint support for earlier version of PostgreSQL.
self.features.uses_savepoints = False
cursor.execute("SET client_encoding to 'UNICODE'")
cursor = UnicodeCursorWrapper(cursor, 'utf-8')
return cursor
def typecast_string(s):
"""
Cast all returned strings to unicode strings.
"""
if not s and not isinstance(s, str):
return s
return smart_unicode(s)
# Register these custom typecasts, because Django expects dates/times to be
# in Python's native (standard-library) datetime/time format, whereas psycopg
# use mx.DateTime by default.
try:
Database.register_type(Database.new_type((1082,), "DATE", util.typecast_date))
except AttributeError:
raise Exception("You appear to be using psycopg version 2. Set your DATABASE_ENGINE to 'postgresql_psycopg2' instead of 'postgresql'.")
Database.register_type(Database.new_type((1083,1266), "TIME", util.typecast_time))
Database.register_type(Database.new_type((1114,1184), "TIMESTAMP", util.typecast_timestamp))
Database.register_type(Database.new_type((16,), "BOOLEAN", util.typecast_boolean))
Database.register_type(Database.new_type((1700,), "NUMERIC", util.typecast_decimal))
Database.register_type(Database.new_type(Database.types[1043].values, 'STRING', typecast_string))