Files
deb-kazoo/kazoo/testing/harness.py
2012-09-04 10:49:20 +02:00

143 lines
3.8 KiB
Python

"""Kazoo testing harnesses"""
import atexit
import logging
import os
import uuid
import threading
import unittest
from kazoo.client import KazooClient
from kazoo.protocol.states import (
KazooState
)
from kazoo.testing.common import ZookeeperCluster
log = logging.getLogger(__name__)
CLUSTER = None
def get_global_cluster():
global CLUSTER
if CLUSTER is None:
ZK_HOME = os.environ.get("ZOOKEEPER_PATH")
assert ZK_HOME, (
"ZOOKEEPER_PATH environment variable must be defined.\n "
"For deb package installations this is /usr/share/java")
CLUSTER = ZookeeperCluster(ZK_HOME)
atexit.register(lambda cluster: cluster.terminate(), CLUSTER)
return CLUSTER
class KazooTestHarness(object):
"""Harness for testing code that uses Kazoo
This object can be used directly or as a mixin. It supports starting
and stopping a complete ZooKeeper cluster locally and provides an
API for simulating errors and expiring sessions.
Example::
class MyTestCase(unittest.TestCase, KazooTestHarness):
def setUp(self):
self.setup_zookeeper()
# additional test setup
def tearDown(self):
self.teardown_zookeeper()
def test_something(self):
something_that_needs_a_kazoo_client(self.client)
def test_something_else(self):
something_that_needs_zk_servers(self.servers)
"""
def __init__(self):
self.client = None
@property
def cluster(self):
return get_global_cluster()
@property
def servers(self):
return ",".join([s.address for s in self.cluster])
def _get_nonchroot_client(self):
return KazooClient(self.servers)
def _get_client(self, **kwargs):
return KazooClient(self.hosts, **kwargs)
def expire_session(self, client_id=None):
"""Force ZK to expire a client session
:param client_id: id of client to expire. If unspecified, the id of
self.client will be used.
"""
client_id = client_id or self.client.client_id
lost = threading.Event()
def watch_loss(state):
if state == KazooState.LOST:
lost.set()
return True
self.client.add_listener(watch_loss)
client = KazooClient(self.hosts, client_id=client_id, timeout=0.8)
client.start()
client.stop()
self.client.get_async('/')
lost.wait()
def setup_zookeeper(self):
"""Create a ZK cluster and chrooted :class:`KazooClient`
The cluster will only be created on the first invocation and won't be
fully torn down until exit.
"""
if not self.cluster[0].running:
self.cluster.start()
namespace = "/kazootests" + uuid.uuid4().hex
self.hosts = self.servers + namespace
self.client = self._get_client(timeout=0.8)
self.client.start()
self.client.ensure_path("/")
def teardown_zookeeper(self):
"""Clean up any ZNodes created during the test
"""
if not self.cluster[0].running:
self.cluster.start()
if self.client.connected:
self.client.delete('/', recursive=True)
self.client.stop()
self.client.stop()
del self.client
else:
client = self._get_client()
client.start()
client.delete('/', recursive=True)
client.stop()
del client
def add_errors(self, errors):
self.client.zookeeper = ZookeeperErrors(errors, self.client.handler)
class KazooTestCase(unittest.TestCase, KazooTestHarness):
def setUp(self):
self.setup_zookeeper()
def tearDown(self):
self.teardown_zookeeper()