# -*- coding: utf-8 -*-
"""
Created on Sun Nov 13 00:00:06 2016

@author: ergo
"""

import select
import psycopg2
import psycopg2.extensions
import threading

def notify(conn):
    print "Waiting for notifications on channel 'cats'"
    while True:
        if select.select([conn],[],[],1) != ([],[],[]):
            conn.poll()
            while conn.notifies:
                notify = conn.notifies.pop(0)
                print "Got NOTIFY:", notify.pid, notify.channel, notify.payload
                print "Must refresh cache"

conn = psycopg2.connect("host=<host> dbname=<dbname> user=<user> password=<password>")
conn.set_isolation_level(psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT)

curs = conn.cursor()
curs.execute("LISTEN cats;")

t = threading.Thread(target=notify, args=(conn,))

t.start()