psycopg2/sandbox/test_green_error.py
Daniele Varrazzo 58d048198f Close the connection on error in callback
Unfortunately PQcancel blocks, so it's not better than PQgetResult.
It has been suggested to use PQreset in non-blocking way but this would give
the Python program the burden of handling a connection done but not configured
in an unexpected place.
2012-10-09 02:01:29 +01:00

82 lines
1.7 KiB
Python

#!/usr/bin/env python
"""Test for issue #113: test with error during green processing
"""
DSN = 'dbname=test'
import eventlet.patcher
eventlet.patcher.monkey_patch()
import os
import signal
from time import sleep
import psycopg2
from psycopg2 import extensions
from eventlet.hubs import trampoline
# register a test wait callback that fails if SIGHUP is received
panic = []
def wait_cb(conn):
"""A wait callback useful to allow eventlet to work with Psycopg."""
while 1:
if panic:
raise Exception('whatever')
state = conn.poll()
if state == extensions.POLL_OK:
break
elif state == extensions.POLL_READ:
trampoline(conn.fileno(), read=True)
elif state == extensions.POLL_WRITE:
trampoline(conn.fileno(), write=True)
else:
raise psycopg2.OperationalError(
"Bad result from poll: %r" % state)
extensions.set_wait_callback(wait_cb)
# SIGHUP handler to inject a fail in the callback
def handler(signum, frame):
panic.append(True)
signal.signal(signal.SIGHUP, handler)
# Simulate another green thread working
def worker():
while 1:
print "I'm working"
sleep(1)
eventlet.spawn(worker)
# You can unplug the network cable etc. here.
# Kill -HUP will raise an exception in the callback.
print "PID", os.getpid()
conn = psycopg2.connect(DSN)
curs = conn.cursor()
try:
for i in range(1000):
curs.execute("select %s, pg_sleep(1)", (i,))
r = curs.fetchone()
print "selected", r
except BaseException, e:
print "got exception:", e.__class__.__name__, e
if conn.closed:
print "the connection is closed"
else:
conn.rollback()
curs.execute("select 1")
print curs.fetchone()