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Created March 21, 2013 15:28
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import sys
import tornado.ioloop
import psycopg2
import psycopg2.extensions
io_loop = tornado.ioloop.IOLoop.instance()
conn = psycopg2.connect('dbname=mytest user=lbolla password=secret')
def listen(ch):
'''Listen to a channel.'''
curs = conn.cursor()
curs.execute("LISTEN %s;" % ch)
def receive(fd, events):
'''Receive a notify message from the channel we are listening.'''
state = conn.poll()
if state == psycopg2.extensions.POLL_OK:
if conn.notifies:
notify = conn.notifies.pop()
io_loop.add_handler(conn.fileno(), receive, io_loop.READ)
def talk(who, ch):
# Connections are thread-safe, but cursors are not
curs = conn.cursor()
def _talk():
while True:
what = input()
msg = '[%s] %s: %s' % (ch, who, what)
# Notify all of what you just said
curs.execute("NOTIFY %s, '%s';" % (ch, msg))
# Run in a separate thread: we could also monitor stdin into the IOLoop...
if __name__ == '__main__':
who, ch = sys.argv[1:3]
# Always listen before talk!
talk(who, ch)
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Hello, when I run this program and write hello as a message it throws this exception:


Exception in thread Thread-1:

Traceback (most recent call last):

File "/usr/lib/python2.7/", line 551, in __bootstrap_inner

File "/usr/lib/python2.7/", line 504, in run

self.__target(_self.__args, *_self.__kwargs)

File "", line 34, in _talk

what = input()

File "", line 1, in

NameError: name 'hello' is not defined

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I love this :)

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