Обсуждение: listen/notify with python pgdb

[postgresql 7.3, python 2.3a1, pygresql-3.4-pre021201]
Does anyone use listen/notify with pgdb, the python DB-API
interface?  I've done a crude hack, but maybe someone has a nicer one?
{Yes, I know notify is not part of the python DB-API: I'm trying
to stay as close to portable API's and still get the work done...}

Here's what I'm doing:
#pgdb_extended.py
'''This is a small wrapper module for pgdb, the Python DB-SIG 2.0
compliant implentation for postgresql access from python.
This wrapper adds just one member function, viz. 'pgdbCnx.getnotify()'.
getnotify just calls the postgresql libpq C API function getnotify() to
get notify messages resulting corresponding to sql 'listen' commands that
have been made.'''

from pgdb import *

def getnotify(self):       return self._pgdbCnx__cnx.getnotify()

pgdbCnx.getnotify = getnotify


-- George


-- I cannot think why the whole bed of the ocean isnot one solid mass of oysters, so prolific they seem. Ah,I am
wandering!Strange how the brain controls the brain!-- Sherlock Holmes in "The Dying Detective"
 

george young wrote:
> [postgresql 7.3, python 2.3a1, pygresql-3.4-pre021201]
> Does anyone use listen/notify with pgdb, the python DB-API
> interface?  I've done a crude hack, but maybe someone has a nicer one?

we are doing it quite extensively in our "gnumed" project, and it works 
to our satisfaction.

We run the "listener" in a background thread which then posts messages 
on receiving backend notifications.

However, we are using the pyPgSql python adapter, not the pgdb one.
Have a look at 

http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/gnumed/gnumed/gnumed/client/python-common/gmBackendListener.py?rev=HEAD&content-type=text/x-python

Horst