Apache Curator Unimplemented Errors When Trying to Create zNodes - apache

Question

I'm attempting to use Apache Curator with a dockerized zookeeper instance and no matter how I attempt to connect I always end up with a
org.apache.zookeeper.KeeperException$UnimplementedException:
KeeperErrorCode = Unimplemented for...
error. I've tried making sense of the documentation but I'm not getting anywhere. I've logged into the zookeeper CLI and ensured the port number is correct thusly:
snerd#powerglove:~$ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 31f1093495ba compose_zookeeper "/opt/zookeeper/bin/ 3 weeks ago Up About a minute 0.0.0.0:32770->2181/tcp,
0.0.0.0:32769->2888/tcp, 0.0.0.0:32768->3888/tcp zookeeper
here is the code I'm trying to use:
public class App {
public static void main( String[] args ) {
CuratorFramework client = CuratorFrameworkFactory.newClient("0.0.0.0:32770", new RetryUntilElapsed(3000, 1000));
client.start();
try {
client.create().forPath("/larry-smells/foop", "tuna?".getBytes());
} catch (Exception e) {
System.out.println(e.toString());
}
}
}
As far as I can tell from the Curator getting started page, this should work. What am I missing?
edit1
just figured out that I'm able to pull data out of the zookeeper ensemble thusly:
System.out.println(new String(curatorFramework.getData().forPath("/larry-smells")));
but the create command is still blowing up.
edit2
stacktrace of the error:
org.apache.zookeeper.KeeperException$UnimplementedException:
KeeperErrorCode = Unimplemented for /larry-smells/foop at
org.apache.zookeeper.KeeperException.create(KeeperException.java:103)
at
org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
at org.apache.zookeeper.ZooKeeper.create(ZooKeeper.java:1297) at
org.apache.curator.framework.imps.CreateBuilderImpl$17.call(CreateBuilderImpl.java:1040)
at
org.apache.curator.framework.imps.CreateBuilderImpl$17.call(CreateBuilderImpl.java:1023)
at
org.apache.curator.connection.StandardConnectionHandlingPolicy.callWithRetry(StandardConnectionHandlingPolicy.java:67)
at org.apache.curator.RetryLoop.callWithRetry(RetryLoop.java:99) at
org.apache.curator.framework.imps.CreateBuilderImpl.pathInForeground(CreateBuilderImpl.java:1020)
at
org.apache.curator.framework.imps.CreateBuilderImpl.protectedPathInForeground(CreateBuilderImpl.java:501)
at
org.apache.curator.framework.imps.CreateBuilderImpl.forPath(CreateBuilderImpl.java:491)
at
org.apache.curator.framework.imps.CreateBuilderImpl$4.forPath(CreateBuilderImpl.java:367)
at
org.apache.curator.framework.imps.CreateBuilderImpl$4.forPath(CreateBuilderImpl.java:309)
at com.mycompany.app.App.main(App.java:35)

Answer 1

Edit: Apparently this error can occur if you're using the wrong combination of Curator in combination with Zookeeper. From curator.apache.org :
Curator 2.x.x - compatible with both ZooKeeper 3.4.x and ZooKeeper 3.5.x
Curator 3.x.x - compatible only with ZooKeeper 3.5.x and includes support for new features such as dynamic reconfiguration, etc.
It's hard to pinpoint your problem with only that error-code and not a stack trace, but some improvements I would suggest to make your application more stable is:
public class App {
public static void main( String[] args ) {
CuratorFramework client = CuratorFrameworkFactory.newClient("0.0.0.0:32770", new RetryUntilElapsed(3000, 1000));
client.start();
try {
//make sure you're connected to zookeeper.
client.blockUntilConnected();
//Make sure the parents are created.
client.create().creatingParentsIfNeeded().forPath("/larry-smells/foop", "tuna?".getBytes());
} catch (Exception e) {
System.out.println(e.toString());
}
}
}

Answer 2

I also faced a similar exception, I used the below dependencies which are compatible and helps me to resolve the exception.
<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.4.6</version>
</dependency>
<dependency>
<groupId>org.apache.curator</groupId>
<artifactId>curator-framework</artifactId>
<version>4.0.1</version>
</dependency>
<dependency>
<groupId>org.apache.curator</groupId>
<artifactId>curator-x-discovery</artifactId>
<version>4.0.1</version>
</dependency>

Answer 3

I had the same problem.
I tried to use inTransaction () as explained here: http://www.programcreek.com/java-api-examples/index.php?api=org.apache.curator.framework.CuratorFramework on exercise 6
and seems to work.
client.inTransaction ().create().forPath("/larry-smells/foop", "tuna?".getBytes()).and ().commit ();

Answer 4

The issue is caused because of incompatibility.
To fix this, you need to change the version like it's explained here:
https://curator.apache.org/zk-compatibility.html
If this doesn't work, just look for the newest curator version which depends on a 3.4.x zookeeper version (currently '2.12.0').

Answer 5

#Massimo Da Ros solution works, but in new version Curator 4.0.0 inTransaction is deprecated, it's recommented use transaction method like below:
CuratorOp op = client.transactionOp().create()
.withMode(CreateMode.PERSISTENT)
.withACL(Ids.OPEN_ACL_UNSAFE)
.forPath("/test", "Data".getBytes());
result = client.transaction().forOperations(op).get(0).toString();

Answer 6

I faced similiar problem. I was using spring-cloud-starter-zookeeper-discovery which by itself of course has compatible zookeeper and curator versions.
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zookeeper-discovery</artifactId>
</dependency>
I checked the dependency tree and spring-cloud-starter-zookeeper-discovery Version 3.1.1. was using zookeeper Version 3.6.0
The problem was, in my docker-compose.yml I was using zookeeper Version 3.4!
So make sure your docker-compose.yml zookeeper version fits your maven zookeeper version.
version: "3.8"
services:
zookeeper:
container_name: zookeeper
image: zookeeper:3.6 <----------------- zookeeper version
ports:
- "2181:2181"