class DatabaseClass:
################
def __init__(self):
self.initialized = False
self.connectString = None
##################
def __del__(self):
self.close()
########################################
def connect(self, connectString=None):
if connectString is None:
from pgcredentials import connectString
self.connectString = connectString
self.setup()
################
def setup(self):
if self.initialized:
return
if not self.connectString:
raise ValueError(
'No connection string set, call '
'"connection(connectString)" first.')
from psycopg2.extras import DictConnection
self.connection = DictConnection(self.connectString)
self.initialized = True
################
def close(self):
if not self.initialized:
return
self.connection.close()
self.connection = None
self.initialized = False
##############################
def query(self, query, *args):
self.setup()
cursor = self.connection.cursor()
cursor.execute(query, args)
return(CursorHelper(cursor))
##########################
def queryone(self, *args):
'''Like query(), but if you are expecting only one result.
Either returns None if there were no results returned, or the row.
'''
try:
ret = self.query(*args)[0]
except IndexError:
return(None)
return(ret)
#################
def commit(self):
self.setup()
self.connection.commit()
###################
def rollback(self):
self.setup()
self.connection.rollback()
class DatabaseClass:
################
def __init__(self):
self.initialized = False
self.connectString = None
##################
def __del__(self):
self.close()
########################################
def connect(self, connectString = None):
if connectString == None:
from pgcredentials import connectString
self.connectString = connectString
self.setup()
################
def setup(self):
if self.initialized: return
if not self.connectString:
raise ValueError('No connection string set, call '
'"connection(connectString)" first.')
from psycopg2.extras import DictConnection
self.connection = DictConnection(self.connectString)
self.initialized = True
################
def close(self):
if not self.initialized: return
self.connection.close()
self.connection = None
self.initialized = False
##############################
def query(self, query, *args):
self.setup()
cursor = self.connection.cursor()
cursor.execute(query, args)
return(CursorHelper(cursor))
##########################
def queryone(self, *args):
'''Like query(), but if you are expecting only one result.
Either returns None if there were no results returned, or the row.
'''
try:
ret = self.query(*args)[0]
except IndexError:
return(None)
return(ret)
###############################################
def insert(self, table, dict = None, **kwargs):
'''Insert a row into the specified table, using the keyword arguments
or dictionary elements as the fields. If a dictionary is specified
with keys matching kwargs, then the dictionary takes precedence.
For example:
insert('users', name = 'Sean', uid = 10, password = '******')
will run the SQL:
INSERT INTO users ( name, uid, password ) VALUES ( 'Sean', 10, 'xyzzy')
'''
if dict is not None: kwargs.update(dict)
values = kwargs.values()
cmd = ('INSERT INTO %s ( %s ) VALUES ( %s )'
% ( table, ','.join(kwargs.keys()),
','.join(['%s'] * len(values)), ))
self.query(cmd, *values)
#################
def commit(self):
self.setup()
self.connection.commit()
###################
def rollback(self):
self.setup()
self.connection.rollback()
