ZooKeeper: throw correct exception code in get method [#METR-16142]

libs/libzkutil/include/zkutil/ZooKeeper.h

@@ -120,7 +120,7 @@ public:
 	/** Не бросает исключение при следующих ошибках:
 	  *  - Такой ноды нет. В таком случае возвращает false.
 	  */
-	bool tryGet(const std::string & path, std::string & res, Stat * stat = nullptr, EventPtr watch = nullptr);
+	bool tryGet(const std::string & path, std::string & res, Stat * stat = nullptr, EventPtr watch = nullptr, int * code = nullptr);
 
 	void set(const std::string & path, const std::string & data,
 			int32_t version = -1, Stat * stat = nullptr);

libs/libzkutil/src/ZooKeeper.cpp

@@ -372,14 +372,15 @@ int32_t ZooKeeper::getImpl(const std::string & path, std::string & res, Stat * s
 
 std::string ZooKeeper::get(const std::string & path, Stat * stat, EventPtr watch)
 {
+	int code;
 	std::string res;
-	if (tryGet(path, res, stat, watch))
+	if (tryGet(path, res, stat, watch, &code))
 		return res;
 	else
-		throw KeeperException("Can't get data for node " + path + ": node doesn't exist");
+		throw KeeperException("Can't get data for node " + path + ": node doesn't exist", code);
 }
 
-bool ZooKeeper::tryGet(const std::string & path, std::string & res, Stat * stat_, EventPtr watch)
+bool ZooKeeper::tryGet(const std::string & path, std::string & res, Stat * stat_, EventPtr watch, int * return_code)
 {
 	int32_t code = retry(std::bind(&ZooKeeper::getImpl, this, std::ref(path), std::ref(res), stat_, watch));
 
@@ -387,6 +388,9 @@ bool ZooKeeper::tryGet(const std::string & path, std::string & res, Stat * stat_
 			code == ZNONODE))
 		throw KeeperException(code, path);
 
+	if (return_code)
+		*return_code = code;
+
 	return code == ZOK;
 }