Add zookeeper test infrastructure

This adds a per-test zookeeper server fixture and demonstrates
its use in preparation for actual zookeeper use.

Change-Id: I99ac519057cdd9d9c829928e0e12ece65b0a5c43
Depends-On: I66d2bc90eb350424c051f480b4102209054ce2eb

nodepool/tests/__init__.py

@@ -109,6 +109,102 @@ class GearmanServerFixture(fixtures.Fixture):
                 raise
 
 
+class ZookeeperServerFixture(fixtures.Fixture):
+    def __init__(self, port=0):
+        self._port = port
+
+    def setUp(self):
+        super(ZookeeperServerFixture, self).setUp()
+
+        # Get the local port range, we're going to pick one at a time
+        # at random to try.
+        with open('/proc/sys/net/ipv4/ip_local_port_range') as f:
+            line = f.readline()
+            begin, end = map(int, line.split())
+
+        zookeeper_fixtures = os.path.join(os.path.dirname(__file__),
+                                          'fixtures', 'zookeeper')
+
+        # Make a tmpdir to hold the config file, zookeeper data dir,
+        # and log file.
+        tmp_root = self.useFixture(fixtures.TempDir()).path
+        with open(os.path.join(zookeeper_fixtures, 'log4j.properties')) as i:
+            with open(os.path.join(tmp_root, 'log4j.properties'), 'w') as o:
+                o.write(i.read())
+
+        config_path = os.path.join(tmp_root, 'zoo.cfg')
+        log_path = os.path.join(tmp_root, 'zookeeper.log')
+
+        classpath = [
+            tmp_root,
+            '/usr/share/java/jline.jar',
+            '/usr/share/java/log4j-1.2.jar',
+            '/usr/share/java/xercesImpl.jar',
+            '/usr/share/java/xmlParserAPIs.jar',
+            '/usr/share/java/netty.jar',
+            '/usr/share/java/slf4j-api.jar',
+            '/usr/share/java/slf4j-log4j12.jar',
+            '/usr/share/java/zookeeper.jar',
+        ]
+        classpath = ':'.join(classpath)
+
+        args = ['/usr/bin/java', '-cp', classpath,
+                '-Dzookeeper.log.dir=%s' % (tmp_root,),
+                '-Dzookeeper.root.logger=INFO,ROLLINGFILE',
+                'org.apache.zookeeper.server.quorum.QuorumPeerMain',
+                config_path]
+
+        found_port = False
+
+        # Try a random port in the local port range one at a time
+        # until we find one that's available.
+        while not found_port:
+            port = random.randrange(begin, end)
+
+            # Write a config file with this port.
+            with open(os.path.join(zookeeper_fixtures, 'zoo.cfg')) as i:
+                with open(config_path, 'w') as o:
+                    o.write(i.read().format(datadir=os.path.join(tmp_root, 'data'),
+                                            port=port))
+
+            # Run zookeeper.
+            p = subprocess.Popen(args)
+
+            # Wait up to 30 seconds to figure out if it has started.
+            for x in range(30):
+                r = self._checkZKLog(log_path)
+                if r is True:
+                    found_port = True
+                    break
+                elif r is False:
+                    break
+                time.sleep(1)
+
+            if not found_port:
+                p.kill()
+                p.wait()
+
+        if found_port:
+            self.zookeeper_port = port
+            self.zookeeper_process = p
+            self.addCleanup(self.shutdownZookeeper)
+
+    def _checkZKLog(self, path):
+        if not os.path.exists(path):
+            return None
+        with open(path) as f:
+            for line in f:
+                if 'Snapshotting:' in line:
+                    return True
+                if 'Address already in use' in line:
+                    return False
+        return None
+
+    def shutdownZookeeper(self):
+        self.zookeeper_process.kill()
+        self.zookeeper_process.wait()
+
+
 class GearmanClient(gear.Client):
     def __init__(self):
         super(GearmanClient, self).__init__(client_id='test_client')
@@ -397,3 +493,11 @@ class DBTestCase(BaseTestCase):
 class IntegrationTestCase(DBTestCase):
     def setUpFakes(self):
         pass
+
+
+class ZKTestCase(BaseTestCase):
+    def setUp(self):
+        super(ZKTestCase, self).setUp()
+        f = ZookeeperServerFixture()
+        self.useFixture(f)
+        self.zookeeper_port = f.zookeeper_port

nodepool/tests/fixtures/zookeeper/log4j.properties

@@ -0,0 +1,51 @@
+#
+# ZooKeeper Logging Configuration
+#
+
+# Format is "<default threshold> (, <appender>)+
+
+log4j.rootLogger=${zookeeper.root.logger}
+
+# Example: console appender only
+# log4j.rootLogger=INFO, CONSOLE
+
+# Example with rolling log file
+#log4j.rootLogger=DEBUG, CONSOLE, ROLLINGFILE
+
+# Example with rolling log file and tracing
+#log4j.rootLogger=TRACE, CONSOLE, ROLLINGFILE, TRACEFILE
+
+#
+# Log INFO level and above messages to the console
+#
+log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
+log4j.appender.CONSOLE.Threshold=INFO
+log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
+log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} - %-5p [%t:%C{1}@%L] - %m%n
+
+#
+# Add ROLLINGFILE to rootLogger to get log file output
+#    Log DEBUG level and above messages to a log file
+log4j.appender.ROLLINGFILE=org.apache.log4j.RollingFileAppender
+log4j.appender.ROLLINGFILE.Threshold=DEBUG
+log4j.appender.ROLLINGFILE.File=${zookeeper.log.dir}/zookeeper.log
+
+# Max log file size of 10MB
+log4j.appender.ROLLINGFILE.MaxFileSize=10MB
+# uncomment the next line to limit number of backup files
+#log4j.appender.ROLLINGFILE.MaxBackupIndex=10
+
+log4j.appender.ROLLINGFILE.layout=org.apache.log4j.PatternLayout
+log4j.appender.ROLLINGFILE.layout.ConversionPattern=%d{ISO8601} - %-5p [%t:%C{1}@%L] - %m%n
+
+
+#
+# Add TRACEFILE to rootLogger to get log file output
+#    Log DEBUG level and above messages to a log file
+log4j.appender.TRACEFILE=org.apache.log4j.FileAppender
+log4j.appender.TRACEFILE.Threshold=TRACE
+log4j.appender.TRACEFILE.File=${zookeeper.log.dir}/zookeeper_trace.log
+
+log4j.appender.TRACEFILE.layout=org.apache.log4j.PatternLayout
+### Notice we are including log4j's NDC here (%x)
+log4j.appender.TRACEFILE.layout.ConversionPattern=%d{ISO8601} - %-5p [%t:%C{1}@%L][%x] - %m%n

nodepool/tests/fixtures/zookeeper/zoo.cfg

@@ -0,0 +1,5 @@
+tickTime=2000
+initLimit=10
+syncLimit=5
+dataDir={datadir}
+clientPort={port}

nodepool/tests/test_builder.py

@@ -18,6 +18,7 @@ import time
 import threading
 
 import fixtures
+import kazoo.client
 
 from nodepool import builder, exceptions, fakeprovider, tests
 
@@ -147,3 +148,9 @@ class TestNodepoolBuilder(tests.DBTestCase):
                     # We failed to upload first_fail_id and have
                     # moved onto another upload that will fail.
                     break
+
+class TestZookeeper(tests.ZKTestCase):
+    def test_zk(self):
+        zk = kazoo.client.KazooClient(hosts='127.0.0.1:%s' % self.zookeeper_port)
+        zk.start()
+        zk.get('/')

requirements.txt

@@ -19,3 +19,4 @@ os-client-config>=1.2.0
 shade>=0.12.0
 diskimage-builder
 voluptuous
+kazoo