relstorage/relstorage/adapters/tests/test_replica.py

137 lines
5.1 KiB
Python

##############################################################################
#
# Copyright (c) 2009 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
import unittest
class ReplicaSelectorTests(unittest.TestCase):
def setUp(self):
import os
import tempfile
fd, self.fn = tempfile.mkstemp()
os.write(fd,
b"# Replicas\n\nexample.com:1234\nlocalhost:4321\n"
b"\nlocalhost:9999\n")
os.close(fd)
def tearDown(self):
import os
os.remove(self.fn)
def test__read_config_normal(self):
from relstorage.adapters.replica import ReplicaSelector
rs = ReplicaSelector(self.fn, 600.0)
self.assertEqual(rs._replicas,
['example.com:1234', 'localhost:4321', 'localhost:9999'])
def test__read_config_empty(self):
from relstorage.adapters.replica import ReplicaSelector
open(self.fn, 'w').close() # truncate the replica list file
self.assertRaises(IndexError, ReplicaSelector, self.fn, 600.0)
def test__is_config_modified(self):
from relstorage.adapters.replica import ReplicaSelector
import time
rs = ReplicaSelector(self.fn, 600.0)
self.assertEqual(rs._is_config_modified(), False)
# change the file
rs._config_modified = 0
# don't check the file yet
rs._config_checked = time.time() + 3600
self.assertEqual(rs._is_config_modified(), False)
# now check the file
rs._config_checked = 0
self.assertEqual(rs._is_config_modified(), True)
def test__select(self):
from relstorage.adapters.replica import ReplicaSelector
rs = ReplicaSelector(self.fn, 600.0)
rs._select(0)
self.assertEqual(rs._current_replica, 'example.com:1234')
self.assertEqual(rs._current_index, 0)
self.assertEqual(rs._expiration, None)
rs._select(1)
self.assertEqual(rs._current_replica, 'localhost:4321')
self.assertEqual(rs._current_index, 1)
self.assertNotEqual(rs._expiration, None)
def test_current(self):
from relstorage.adapters.replica import ReplicaSelector
rs = ReplicaSelector(self.fn, 600.0)
self.assertEqual(rs.current(), 'example.com:1234')
# change the file and get the new current replica
f = open(self.fn, 'w')
f.write('localhost\nalternate\n')
f.close()
rs._config_checked = 0
rs._config_modified = 0
self.assertEqual(rs.current(), 'localhost')
# switch to the alternate
rs._select(1)
self.assertEqual(rs.current(), 'alternate')
# expire the alternate
rs._expiration = 0
self.assertEqual(rs.current(), 'localhost')
def test_next_iteration(self):
from relstorage.adapters.replica import ReplicaSelector
rs = ReplicaSelector(self.fn, 600.0)
# test forward iteration
self.assertEqual(rs.current(), 'example.com:1234')
self.assertEqual(rs.next(), 'localhost:4321')
self.assertEqual(rs.next(), 'localhost:9999')
self.assertEqual(rs.next(), None)
# test iteration that skips over the replica that failed
self.assertEqual(rs.current(), 'example.com:1234')
self.assertEqual(rs.next(), 'localhost:4321')
self.assertEqual(rs.current(), 'localhost:4321')
# next() after current() indicates the last replica failed
self.assertEqual(rs.next(), 'example.com:1234')
self.assertEqual(rs.next(), 'localhost:9999')
self.assertEqual(rs.next(), None)
def test_next_only_one_server(self):
from relstorage.adapters.replica import ReplicaSelector
f = open(self.fn, 'w')
f.write('localhost\n')
f.close()
rs = ReplicaSelector(self.fn, 600.0)
self.assertEqual(rs.current(), 'localhost')
self.assertEqual(rs.next(), None)
def test_next_with_new_conf(self):
from relstorage.adapters.replica import ReplicaSelector
rs = ReplicaSelector(self.fn, 600.0)
self.assertEqual(rs.current(), 'example.com:1234')
self.assertEqual(rs.next(), 'localhost:4321')
# interrupt the iteration by changing the replica conf file
f = open(self.fn, 'w')
f.write('example.com:9999\n')
f.close()
rs._config_checked = 0
rs._config_modified = 0
self.assertEqual(rs.next(), 'example.com:9999')
self.assertEqual(rs.next(), None)
def test_suite():
suite = unittest.TestSuite()
suite.addTest(unittest.makeSuite(ReplicaSelectorTests))
return suite
if __name__ == '__main__':
unittest.main(defaultTest='test_suite')