psycopg2/tests/test_notify.py

#!/usr/bin/env python
from testutils import unittest

import psycopg2
from psycopg2 import extensions
from testconfig import dsn

import sys
import time
import select
import signal
from subprocess import Popen, PIPE


class NotifiesTests(unittest.TestCase):

    def setUp(self):
        self.conn = psycopg2.connect(dsn)

    def tearDown(self):
        self.conn.close()

    def autocommit(self, conn):
        """Set a connection in autocommit mode."""
        conn.set_isolation_level(extensions.ISOLATION_LEVEL_AUTOCOMMIT)

    def listen(self, name):
        """Start listening for a name on self.conn."""
        curs = self.conn.cursor()
        curs.execute("LISTEN " + name)
        curs.close()

    def notify(self, name, sec=0, payload=None):
        """Send a notification to the database, eventually after some time."""
        if payload is None:
            payload = ''
        else:
            payload = ", %r" % payload

        script = ("""\
import time
time.sleep(%(sec)s)
import psycopg2
import psycopg2.extensions
conn = psycopg2.connect(%(dsn)r)
conn.set_isolation_level(psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT)
print conn.get_backend_pid()
curs = conn.cursor()
curs.execute("NOTIFY " %(name)r %(payload)r)
curs.close()
conn.close()
"""
            % { 'dsn': dsn, 'sec': sec, 'name': name, 'payload': payload})

        return Popen([sys.executable, '-c', script], stdout=PIPE)

    def test_notifies_received_on_poll(self):
        self.autocommit(self.conn)
        self.listen('foo')

        proc = self.notify('foo', 1)

        t0 = time.time()
        ready = select.select([self.conn], [], [], 5)
        t1 = time.time()
        self.assert_(0.99 < t1 - t0 < 4, t1 - t0)

        pid = int(proc.communicate()[0])
        self.assertEqual(0, len(self.conn.notifies))
        self.assertEqual(extensions.POLL_OK, self.conn.poll())
        self.assertEqual(1, len(self.conn.notifies))
        self.assertEqual(pid, self.conn.notifies[0][0])
        self.assertEqual('foo', self.conn.notifies[0][1])

    def test_many_notifies(self):
        self.autocommit(self.conn)
        for name in ['foo', 'bar', 'baz']:
            self.listen(name)

        pids = {}
        for name in ['foo', 'bar', 'baz', 'qux']:
            pids[name] = int(self.notify(name).communicate()[0])

        self.assertEqual(0, len(self.conn.notifies))
        for i in range(10):
            self.assertEqual(extensions.POLL_OK, self.conn.poll())
        self.assertEqual(3, len(self.conn.notifies))

        names = dict.fromkeys(['foo', 'bar', 'baz'])
        for (pid, name) in self.conn.notifies:
            self.assertEqual(pids[name], pid)
            names.pop(name) # raise if name found twice

    def test_notifies_received_on_execute(self):
        self.autocommit(self.conn)
        self.listen('foo')
        pid = int(self.notify('foo').communicate()[0])
        self.assertEqual(0, len(self.conn.notifies))
        self.conn.cursor().execute('select 1;')
        self.assertEqual(1, len(self.conn.notifies))
        self.assertEqual(pid, self.conn.notifies[0][0])
        self.assertEqual('foo', self.conn.notifies[0][1])

    def test_notify_object(self):
        self.autocommit(self.conn)
        self.listen('foo')
        self.notify('foo').communicate()
        time.sleep(0.1)
        self.conn.poll()
        notify = self.conn.notifies[0]
        self.assert_(isinstance(notify, psycopg2.extensions.Notify))

    def test_notify_attributes(self):
        self.autocommit(self.conn)
        self.listen('foo')
        pid = int(self.notify('foo').communicate()[0])
        time.sleep(0.1)
        self.conn.poll()
        self.assertEqual(1, len(self.conn.notifies))
        notify = self.conn.notifies[0]
        self.assertEqual(pid, notify.pid)
        self.assertEqual('foo', notify.channel)
        self.assertEqual('', notify.payload)

    def test_notify_payload(self):
        if self.conn.server_version < 90000:
            return self.skipTest("server version %s doesn't support notify payload"
                % self.conn.server_version)
        self.autocommit(self.conn)
        self.listen('foo')
        pid = int(self.notify('foo', payload="Hello, world!").communicate()[0])
        time.sleep(0.1)
        self.conn.poll()
        self.assertEqual(1, len(self.conn.notifies))
        notify = self.conn.notifies[0]
        self.assertEqual(pid, notify.pid)
        self.assertEqual('foo', notify.channel)
        self.assertEqual('Hello, world!', notify.payload)

    def test_notify_init(self):
        n = psycopg2.extensions.Notify(10, 'foo')
        self.assertEqual(10, n.pid)
        self.assertEqual('foo', n.channel)
        self.assertEqual('', n.payload)
        (pid, channel) = n
        self.assertEqual((pid, channel), (10, 'foo'))

        n = psycopg2.extensions.Notify(42, 'bar', 'baz')
        self.assertEqual(42, n.pid)
        self.assertEqual('bar', n.channel)
        self.assertEqual('baz', n.payload)
        (pid, channel) = n
        self.assertEqual((pid, channel), (42, 'bar'))

    def test_compare(self):
        data = [(10, 'foo'), (20, 'foo'), (10, 'foo', 'bar'), (10, 'foo', 'baz')]
        for d1 in data:
            for d2 in data:
                n1 = psycopg2.extensions.Notify(*d1)
                n2 = psycopg2.extensions.Notify(*d2)
                self.assertEqual((n1 == n2), (d1 == d2))
                self.assertEqual((n1 != n2), (d1 != d2))

    def test_compare_tuple(self):
        from psycopg2.extensions import Notify
        self.assertEqual((10, 'foo'), Notify(10, 'foo'))
        self.assertEqual((10, 'foo'), Notify(10, 'foo', 'bar'))
        self.assertNotEqual((10, 'foo'), Notify(20, 'foo'))
        self.assertNotEqual((10, 'foo'), Notify(10, 'bar'))

    def test_hash(self):
        from psycopg2.extensions import Notify
        self.assertEqual(hash((10, 'foo')), hash(Notify(10, 'foo')))
        self.assertNotEqual(hash(Notify(10, 'foo', 'bar')),
            hash(Notify(10, 'foo')))

def test_suite():
    return unittest.TestLoader().loadTestsFromName(__name__)

if __name__ == "__main__":
    unittest.main()