"""
PostgreSQL database backend for Django.
Requires psycopg 1: http://initd.org/projects/psycopg1
"""
import sys
from django.db import utils
from django.db.backends import *
from django.db.backends.signals import connection_created
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=()):
try:
return self.cursor.execute(smart_str(sql, self.charset), self.format_params(params))
except Database.IntegrityError, e:
raise utils.IntegrityError, utils.IntegrityError(*tuple(e)), sys.exc_info()[2]
except Database.DatabaseError, e:
raise utils.DatabaseError, utils.DatabaseError(*tuple(e)), sys.exc_info()[2]
def executemany(self, sql, param_list):
try:
new_param_list = [self.format_params(params) for params in param_list]
return self.cursor.executemany(sql, new_param_list)
except Database.IntegrityError, e:
raise utils.IntegrityError, utils.IntegrityError(*tuple(e)), sys.exc_info()[2]
except Database.DatabaseError, e:
raise utils.DatabaseError, utils.DatabaseError(*tuple(e)), sys.exc_info()[2]
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.fetchall())
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)
import warnings
warnings.warn(
'The "postgresql" backend has been deprecated. Use "postgresql_psycopg2" instead.',
PendingDeprecationWarning
)
self.features = DatabaseFeatures()
self.ops = DatabaseOperations(self)
self.client = DatabaseClient(self)
self.creation = DatabaseCreation(self)
self.introspection = DatabaseIntrospection(self)
self.validation = BaseDatabaseValidation(self)
def _cursor(self):
new_connection = False
set_tz = False
settings_dict = self.settings_dict
if self.connection is None:
new_connection = True
set_tz = settings_dict.get('TIME_ZONE')
if settings_dict['NAME'] == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured("You need to specify NAME in your Django settings file.")
conn_string = "dbname=%s" % settings_dict['NAME']
if settings_dict['USER']:
conn_string = "user=%s %s" % (settings_dict['USER'], conn_string)
if settings_dict['PASSWORD']:
conn_string += " password='%s'" % settings_dict['PASSWORD']
if settings_dict['HOST']:
conn_string += " host=%s" % settings_dict['HOST']
if settings_dict['PORT']:
conn_string += " port=%s" % settings_dict['PORT']
self.connection = Database.connect(conn_string, **settings_dict['OPTIONS'])
self.connection.set_isolation_level(1) # make transactions transparent to all cursors
connection_created.send(sender=self.__class__)
cursor = self.connection.cursor()
if new_connection:
if set_tz:
cursor.execute("SET TIME ZONE %s", [settings_dict['TIME_ZONE']])
if not hasattr(self, '_version'):
self.__class__._version = get_version(cursor)
if self._version[0:2] < (8, 0):
# No savepoint support for earlier version of PostgreSQL.
self.features.uses_savepoints = False
cursor.execute("SET client_encoding to 'UNICODE'")
return UnicodeCursorWrapper(cursor, 'utf-8')
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 DATABASES.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))
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