[DRILL-5874] NPE in AnonWebUserConnection.cleanupSession()

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.12.0
• Fix Version/s: 1.12.0
• Labels: ready-to-commit
• Assignee: Sorabh Hamirwasia
• Reporter: Paul Rogers
• Reviewer: Paul Rogers
• Created: 12/Oct/17 23:33
• Updated: 30/Oct/17 20:02
• Resolved: 30/Oct/17 20:02

Description

When debugging another issue, I tried to use the Web UI to run the example query:

SELECT * FROM cp.`employee.json` LIMIT 20

The query failed with this error:

Query Failed: An Error Occurred
java.lang.NullPointerException

No stack trace was provided in the log, even at DEBUG level.

Debugging, the problem appears to be deep inside AnonWebUserConnection.cleanupSession():

package io.netty.channel;

public class DefaultChannelPromise ...
    protected EventExecutor executor() {
        EventExecutor e = super.executor();
        if (e == null) {
            return channel().eventLoop();
        } else {
            return e;
        }
    }

In the above, channel() is null. the channel field is also null.

This may indicate that some part of the Web UI was not set up correctly. This is a recent change, as this code worked several days ago.

Issue Links

• links to: GitHub Pull Request #993