zkcpp: added test showing that zkcpp blocks calls forever after session expiration. [#METR-10202]

libs/libzkutil/include/zkutil/Types.h

@@ -26,7 +26,7 @@ typedef std::shared_ptr<boost::ptr_vector<OpResult> > OpResultsPtr;
 typedef std::vector<std::string> Strings;
 
 typedef boost::function<void (WatchEvent::type event, SessionState::type state,
-                         const std::string & path)> WatchFunction;
+							  const std::string & path)> WatchFunction;
 
 struct WatchEventInfo
 {

libs/libzkutil/src/tests/zkcpp_expiration_test.cpp

@@ -0,0 +1,43 @@
+#include <zookeeper/zookeeper.hh>
+
+namespace zk = org::apache::zookeeper;
+
+void stateChanged(zk::WatchEvent::type event, zk::SessionState::type state, const std::string & path)
+{
+	std::cout << "state changed; event: " << zk::WatchEvent::toString(event) << ", state: " << zk::SessionState::toString(state)
+		<< ", path: " << path << std::endl;
+}
+
+int main()
+{
+	zk::ZooKeeper zookeeper;
+	zookeeper.init("example1:2181,example2:2181,example3:2181", 5000, nullptr);
+
+	std::vector<std::string> children;
+	zk::data::Stat stat;
+	zk::ReturnCode::type ret = zookeeper.getChildren("/", nullptr, children, stat);
+
+	std::cout << "getChildren returned " << zk::ReturnCode::toString(ret) << std::endl;
+	std::cout << "children of /:" << std::endl;
+	for (const auto & s : children)
+	{
+		std::cout << s << std::endl;
+	}
+
+	std::cout << "break connection to example1:2181,example2:2181,example3:2181 for at least 5 seconds and enter something" << std::endl;
+	std::string unused;
+	std::cin >> unused;
+
+	children.clear();
+	std::cout << "will getChildren" << std::endl;
+	ret = zookeeper.getChildren("/", nullptr, children, stat);
+
+	std::cout << "getChildren returned " << zk::ReturnCode::toString(ret) << std::endl;
+	std::cout << "children of /:" << std::endl;
+	for (const auto & s : children)
+	{
+		std::cout << s << std::endl;
+	}
+
+	return 0;
+}

libs/libzkutil/src/tests/zkutil_test.cpp

@@ -48,12 +48,6 @@ int main(int argc, char ** argv)
 
 		while (char * line = readline(":3 "))
 		{
-			if (zk.disconnected())
-			{
-				std::cerr << "Disconnected" << std::endl;
-				break;
-			}
-
 			try
 			{
 				std::stringstream ss(line);