RedisClusterNode.hasSameSlotsAs() is unreliable

[jacob-pro]

Bug Report

Current Behavior

When using the RedisClusterNode::hasSameSlotsAs() function to compare nodes retrieved from RedisClusterClient::getPartitions() against nodes from ClusterPartitionParser::parse (via RedisClusterCommands::clusterNodes) it incorrectly returns false.

This is because the nodes in the client partitions table have a slot range of null whereas the parsed nodes have a non null but empty slot range.

The parsed nodes are created with a non-null BitSet even if they have no slots:

https://github.com/lettuce-io/lettuce-core/blob/fc6630e0fdd46e175e1d51a2491732092bb683ff/src/main/java/io/lettuce/core/cluster/models/partitions/RedisClusterNode.java#L102-L103

Whereas cloned nodes are created with a null BitSet if the slots are empty:

https://github.com/lettuce-io/lettuce-core/blob/fc6630e0fdd46e175e1d51a2491732092bb683ff/src/main/java/io/lettuce/core/cluster/models/partitions/RedisClusterNode.java#L122-L125

Updating the slots also leaves the value as null if the new range is empty:

https://github.com/lettuce-io/lettuce-core/blob/fc6630e0fdd46e175e1d51a2491732092bb683ff/src/main/java/io/lettuce/core/cluster/models/partitions/RedisClusterNode.java#L332-L334

Environment

• Lettuce version(s): 6.2.3.RELEASE
• Redis version: 7.0.8

Additional context

Similar / related to:

#1091
#1089

[mp911de]

It makes sense to fix this problem. Since you've looked already into it, do you want to submit a pull request along with a few unit test cases?

[zeze1004]

@mp911de , @jacob-pro
May I take on this issue?
I think it would work to have nodes without slots hold an empty BitSet object(or null) and modify the conditional statement based on #1091 issue.

I really want to give it a try!

[zeze1004]

On second thought🤔🤔🤔, don't need to check the conditions to assigned a slot when creating a node. Just check if it's slot.empty().

What do you think of my opinion? Please review it.🙇🏻🙇🏻🙇🏻