Merge pull request #10 from zopefoundation/fixes-2014-08-27

Fixed, especially for hang on reconnect. (Don't know why travis shows as failing. The last runs there are green.)

.travis.yml

@@ -1,4 +1,7 @@
 language: python
+env:
+    - PYTHON_VER=2.6
+    - PYTHON_VER=2.7
 install:
     - python bootstrap.py
     - bin/buildout

src/zc/zk/README.txt

@@ -1251,6 +1251,14 @@ more, use the help function::
 Change History
 ==============
 
+- Fixed: ZooKeeper operations (including closing ZooKeeper
+  connections) hung after network failures if ZooKeeper sessions were
+  lost and ephemeral nodes (for registered services) had to be
+  re-registered.
+
+- Fixed: Didn't properly handle None values for node data returned by
+  Kazoo 2.0.
+
 2.0.0 (2014-06-02)
 ==================
 

src/zc/zk/__init__.py

@@ -41,7 +41,7 @@ def encode(props):
     return json.dumps(props, separators=(',',':'))
 
 def decode(sdata, path='?'):
-    s = sdata.strip()
+    s = sdata and sdata.strip()
     if not s:
         data = {}
     elif s.startswith('{') and s.endswith('}'):
@@ -141,15 +141,20 @@ def __init__(
         self.state = None
 
         def watch_session(state):
+            restore = False
+            logger.info("watch_session %s" % state)
             if state == kazoo.protocol.states.KazooState.CONNECTED:
-                if self.state == kazoo.protocol.states.KazooState.LOST:
-                    logger.warning("session lost")
+                restore = self.state == kazoo.protocol.states.KazooState.LOST
+                logger.info('connected')
+            self.state = state
+
+            if restore:
+                @zc.thread.Thread
+                def restore():
                     for path, data in self.ephemeral.items():
                         logger.info("restoring ephemeral %s", path)
                         self.create(
                             path, data['data'], data['acl'], ephemeral=True)
-                logger.info('connected')
-            self.state = state
 
         client.add_listener(watch_session)
 

src/zc/zk/disconnectiontests.py

@@ -79,12 +79,16 @@ def log_ephemeral_restoration_on_session_timeout():
     >>> handler.clear()
     >>> zk.client.lose_session()
     >>> print handler
-    zc.zk WARNING
-      session lost
     zc.zk INFO
-      restoring ephemeral /fooservice/providers/test
+      watch_session SUSPENDED
+    zc.zk INFO
+      watch_session LOST
+    zc.zk INFO
+      watch_session CONNECTED
     zc.zk INFO
       connected
+    zc.zk INFO
+      restoring ephemeral /fooservice/providers/test
 
     >>> zk.close()
     """
@@ -138,19 +142,25 @@ def session_timeout_with_child_and_data_watchers():
     ['providers', 'x']
 
     >>> print handler
-    zc.zk WARNING
-      session lost
+    zc.zk INFO
+      watch_session SUSPENDED
+    zc.zk INFO
+      watch_session LOST
+    zc.zk INFO
+      watch_session CONNECTED
     zc.zk INFO
       connected
 
     If changes are made while we're disconnected, we'll still see them:
 
-    >>> @zk.client.lose_session
-    ... def _():
-    ...     zk2 = zc.zk.ZooKeeper('zookeeper.example.com:2181')
-    ...     zk2.set('/fooservice', '{"test": 1}')
-    ...     zk2.create('/fooservice/y')
-    ...     zk2.close()
+    >>> if True:
+    ...     @zk.client.lose_session
+    ...     def _():
+    ...         zk2 = zc.zk.ZooKeeper('zookeeper.example.com:2181')
+    ...         zk2.set('/fooservice', '{"test": 1}')
+    ...         zk2.create('/fooservice/y')
+    ...         zk2.close()
+    ...     import time; time.sleep(1) # threads :/
     properties changed True
     children changed True
 

src/zc/zk/ephemeral_node_recovery_on_session_reestablishment.test

@@ -41,6 +41,11 @@ Some custom data and acl:
         a = 1
         pid = 9999
     >>> zk.client.lose_session()
+
+There be threading thar, so wait:
+
+    >>> import time; time.sleep(1)
+
     >>> zk.print_tree('/fooservice/providers')
     /providers
       /test

src/zc/zk/tests.py

@@ -1031,6 +1031,7 @@ def test_property_loops():
     [(u'a', 1), (u'b', 2)]
 
     >>> zk.close()
+    INFO watch_session SUSPENDED
     >>> logger.uninstall()
     """
 
@@ -1116,6 +1117,16 @@ def backward_compatible_create_recursive():
     >>> zk.close()
     """
 
+def node_data_may_be_None():
+    """
+    >>> zk = zc.zk.ZooKeeper('zookeeper.example.com:2181')
+    >>> _ = zk.client.create('/empty', None)
+    >>> zk.get_properties('/empty')
+    {}
+    >>> zk.close()
+    """
+
+
 event = threading.Event()
 def check_async(show=True, expected_status=0):
     event.clear()