On Wed, 29 Sep 2004 23:47:37 +0200, Thomas Weholt <thomas.weholt@gmail.com> wrote:
Hi,
My code below is an attempt to write a general database-abstraction layer for Twisted. I got one allready supporting SQLite and MySQL ( MSSQL and PostgreSQL in the works ) but it blocks and doesn't use deffereds etc so I thought I'd try to write one that fits better with the Twisted framework. It will mainly be used in web-applications. The basic example is ( and don't laugh, this is my first attempt at using deferreds etc. ) :
Hey Thomas, I think you're pretty close. See below for a couple minor code changes.
from twisted.enterprise import adbapi
class TestConn:
def __init__(self, dbname): self.dbname = dbname self.dbpool = adbapi.ConnectionPool("sqlite", db=dbname)
def returnOk(self, o): return True
def returnFailure(self, o): return False
def returnResult(self, result): return result
def _returnResult(self, deferred, count = None): if count: return self.dbpool.fetchmany(count) else: return self.dbpool.fetchall()
def execSql(self, sql, params = {}): def run(sql, params): return self.dbpool.runQuery(sql, params) d = run(sql, params) d.addCallback(self._returnResult) d.addErrback(self.returnFailure) d.addCallback(self.returnResult)
return d
def fetch(self, sql, params = {}): def run(sql, params): return self.dbpool.runQuery(sql, params) d = run(sql, params) d.addCallback(self.returnResult) d.addErrback(self.returnFailure)
return d
s = TestConn(r'c:\temp\db1.db') print s.execSql('create table table1 (a int, b int)') print s.execSql('insert into table1 (a,b) values (1,1)') print s.execSql('insert into table1 (a,b) values (1,2)') print s.execSql('insert into table1 (a,b) values (2,2)') print s.fetch('select * from table1') print s.fetch('select a from table1')
With the two added returns, you should no longer see None in the output, although you will also not see your actual results. I think this is what you expected, though. Jp