Issues

• fixes Helix fails to connect with Kerberos enabled ZK #3101

Description

Refer #3101 for details on the issue

Tests

• Verified the changes through unit test cases
• Verified Change through Quickstart sample App
  In the Quickstart sample app, I have enabled Zookeeper Kerberos authentication and verified the fix

Quickstart Output Before Fix
Creating cluster: HELIX_QUICKSTART
Adding 2 participants to the cluster
Added participant: localhost_12000
Added participant: localhost_12001
Configuring StateModel: MyStateModel with 1 Leader and 1 Standby
Adding a resource MyResource: with 6 partitions and 2 replicas
Starting Participants
ERROR ZKHelixManager zkClient is not connected after waiting 10000ms., clusterName: HELIX_QUICKSTART, zkAddress: sl73tskrapd1044.visa.com:2181
ERROR ZKHelixManager fail to createClient. retry 1
org.apache.helix.HelixException: HelixManager is not connected within retry timeout for cluster HELIX_QUICKSTART
at org.apache.helix.manager.zk.ZKHelixManager.checkConnected(ZKHelixManager.java:417)
at org.apache.helix.manager.zk.ZKHelixManager.getConfigAccessor(ZKHelixManager.java:688)
at org.apache.helix.manager.zk.ParticipantManager.(ParticipantManager.java:118)
at org.apache.helix.manager.zk.ZKHelixManager.handleNewSessionAsParticipant(ZKHelixManager.java:1441)
at org.apache.helix.manager.zk.ZKHelixManager.handleNewSession(ZKHelixManager.java:1391)
at org.apache.helix.manager.zk.ZKHelixManager.createClient(ZKHelixManager.java:783)
at org.apache.helix.manager.zk.ZKHelixManager.connect(ZKHelixManager.java:818)
at org.apache.helix.examples.Quickstart$MyProcess.start(Quickstart.java:247)
at org.apache.helix.examples.Quickstart.startNodes(Quickstart.java:146)
at org.apache.helix.examples.Quickstart.main(Quickstart.java:164)
ERROR ZKHelixManager fail to createClient. retry 2
org.apache.helix.zookeeper.zkclient.exception.ZkTimeoutException: Waiting to be connected to ZK server has timed out.
at org.apache.helix.zookeeper.zkclient.ZkClient.waitForEstablishedSession(ZkClient.java:2082)
at org.apache.helix.manager.zk.ZKHelixManager.createClient(ZKHelixManager.java:776)
at org.apache.helix.manager.zk.ZKHelixManager.connect(ZKHelixManager.java:818)
at org.apache.helix.examples.Quickstart$MyProcess.start(Quickstart.java:247)
at org.apache.helix.examples.Quickstart.startNodes(Quickstart.java:146)
at org.apache.helix.examples.Quickstart.main(Quickstart.java:164)

Quickstart Output After Fix:

Creating cluster: HELIX_QUICKSTART
Adding 2 participants to the cluster
Added participant: localhost_12000
Added participant: localhost_12001
Configuring StateModel: MyStateModel with 1 Leader and 1 Standby
Adding a resource MyResource: with 6 partitions and 2 replicas
Starting Participants
Started Participant: localhost_12000
Started Participant: localhost_12001
Starting Helix Controller
LeaderStandbyStateModel.onBecomeStandbyFromOffline():localhost_12000 transitioning from OFFLINE to STANDBY for MyResource MyResource_1
LeaderStandbyStateModel.onBecomeStandbyFromOffline():localhost_12000 transitioning from OFFLINE to STANDBY for MyResource MyResource_4
LeaderStandbyStateModel.onBecomeStandbyFromOffline():localhost_12000 transitioning from OFFLINE to STANDBY for MyResource MyResource_3
LeaderStandbyStateModel.onBecomeStandbyFromOffline():localhost_12000 transitioning from OFFLINE to STANDBY for MyResource MyResource_5

• The following tests are written for this issue:

org.apache.helix.zookeeper.impl.client.TestRawZkClient
#testWaitForKeeperStateWithSaslAuthenticated
#testWaitForKeeperStateWithConnectedReadOnly
#testWaitForKeeperStateWithOtherStates
#testWaitForKeeperStateExactMatchStillWorks

• The following is the result of the "mvn test" command on the appropriate module:

(If CI test fails due to known issue, please specify the issue and test PR locally. Then copy & paste the result of "mvn test" to here.)

Changes that Break Backward Compatibility (Optional)

• My PR contains changes that break backward compatibility or previous assumptions for certain methods or API. They include:

(Consider including all behavior changes for public methods or API. Also include these changes in merge description so that other developers are aware of these changes. This allows them to make relevant code changes in feature branches accounting for the new method/API behavior.)

Documentation (Optional)

• In case of new functionality, my PR adds documentation in the following wiki page:

(Link the GitHub wiki you added)

Commits

• My commits all reference appropriate Apache Helix GitHub issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Code Quality

• My diff has been formatted using helix-style.xml
  (helix-style-intellij.xml if IntelliJ IDE is used)