Handle ipv6 literal zookeeper addresses

If you use a ipv6 literal as the host: parameter in zookeeper-services
section, it gets incorretly concatentated with the port when building
the host list.  Detect ipv6 literals and quote them with rfc2732 []'s
when building the host string.

Change-Id: I49a749142e8031be37a08960bf645faca4e97149

nodepool/tests/unit/test_zk.py

@@ -43,6 +43,23 @@ class TestZooKeeper(tests.DBTestCase):
         self.assertEqual('127.0.0.1:2181/test1,127.0.0.2:2182/test2',
                          zk.buildZooKeeperHosts(hosts))
 
+    def test_buildZooKeeperHosts_ipv6(self):
+        hosts = [
+            zk.ZooKeeperConnectionConfig(
+                '2001:4800:7817:103:be76:4eff:fe04:e359', port=2181,
+                chroot='/test1'),
+            zk.ZooKeeperConnectionConfig(
+                '[2002:4800:7817:103:be76:4eff:fe04:e359]', port=2181,
+                chroot='/test2'),
+            zk.ZooKeeperConnectionConfig('127.0.0.2', port=2182,
+                                         chroot='/test3')
+        ]
+        self.assertEqual((
+            '[2001:4800:7817:103:be76:4eff:fe04:e359]:2181/test1,'
+            '[2002:4800:7817:103:be76:4eff:fe04:e359]:2181/test2,'
+            '127.0.0.2:2182/test3'
+        ), zk.buildZooKeeperHosts(hosts))
+
     def test_imageBuildLock(self):
         path = self.zk._imageBuildLockPath("ubuntu-trusty")
         with self.zk.imageBuildLock("ubuntu-trusty", blocking=False):

nodepool/zk.py

@@ -13,6 +13,7 @@
 from contextlib import contextmanager
 from copy import copy
 import abc
+import ipaddress
 import json
 import logging
 import time
@@ -101,6 +102,10 @@ class ZooKeeperConnectionConfig(object):
         self.port = port
         self.chroot = chroot or ''
 
+    def __repr__(self):
+        return "host=%s port=%s chroot=%s" % \
+            (self.host, self.port, self.chroot)
+
 
 def buildZooKeeperHosts(host_list):
     '''
@@ -114,7 +119,16 @@ def buildZooKeeperHosts(host_list):
         raise Exception("'host_list' must be a list")
     hosts = []
     for host_def in host_list:
-        host = '%s:%s%s' % (host_def.host, host_def.port, host_def.chroot)
+        h = host_def.host
+        # If this looks like a ipv6 literal address, make sure it's
+        # quoted in []'s
+        try:
+            addr = ipaddress.ip_address(host_def.host)
+            if addr.version == 6:
+                h = '[%s]' % addr
+        except ValueError:
+            pass
+        host = '%s:%s%s' % (h, host_def.port, host_def.chroot)
         hosts.append(host)
     return ",".join(hosts)
 

releasenotes/notes/zk-ipv6-literal-157af417eef9dc6a.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Zookeeper hosts specified as IPv6 literals will now be configured
+    correctly.