Add a script to print the ZK tree

This script uses a nodepool config file to connect to ZK and print
the entire contents of the ZK tree for debugging purposes.

Change-Id: I31566e15d915e701639325f757d1b917ad93c780

tools/print-zk.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import argparse
+import logging
+
+import nodepool.config
+import nodepool.zk
+
+# A script to print the zookeeper tree given a nodepool config file.
+
+logging.basicConfig()
+
+parser = argparse.ArgumentParser(description='Print the zookeeper tree')
+parser.add_argument('-c', dest='config',
+                    default='/etc/nodepool/nodepool.yaml',
+                    help='path to config file')
+args = parser.parse_args()
+
+config = nodepool.config.loadConfig(args.config)
+
+zk = nodepool.zk.ZooKeeper()
+zk.connect(config.zookeeper_servers.values())
+
+def join(a, b):
+    if a.endswith('/'):
+        return a+b
+    return a+'/'+b
+
+def print_tree(node):
+    data, stat = zk.client.get(node)
+    print "Node: %s %s" % (node, stat)
+    if data:
+        print data
+
+    for child in zk.client.get_children(node):
+        print
+        print_tree(join(node, child))
+
+print_tree('/')
+zk.disconnect()