coderabbitai[bot]
commented
2 months ago Walkthrough
The updates to the JRaft library introduce a new NodeStateListener interface and associated management methods in the Node class. This enhancement allows users to add, remove, and manage listeners that can execute custom logic in response to specific node state changes, such as pre-vote failures and configuration discrepancies. These changes are primarily implemented in the core node handling classes, enhancing the library's extensibility and monitoring capabilities.
Changes
| File Path | Change Summary |
|---|---|
.../jraft/Node.java |
Added methods for managing NodeStateListener instances and introduced NodeStateListener interface. |
.../jraft/core/NodeImpl.java |
Implemented listener management methods and integrated state listener triggers in node state handling. |
🐇✨ In the land of code where the data nodes play, A new listener sprouts, hip hip hooray! It watches, it triggers, without any delay, On state changes it dances, in JRaft's ballet. So here's to the devs, with their code so bright, May your clusters run smoothly, by day and by night. 🌟🐰
Recent Review Status
**Configuration used: CodeRabbit UI**Commits
Files that changed from the base of the PR and between 890033a64d8ed5c8838463f278b940355553e413 and 285715a0bf5405644ccbc687731bc5d15bd19c62.Files selected for processing (2)
* jraft-core/src/main/java/com/alipay/sofa/jraft/Node.java (2 hunks) * jraft-core/src/main/java/com/alipay/sofa/jraft/core/NodeImpl.java (7 hunks)Additional comments not posted (4)
jraft-core/src/main/java/com/alipay/sofa/jraft/Node.java (2)
`353-371`: Ensure thread safety for `NodeStateListener` management methods.Verification successful
--- The verification process has confirmed that the `NodeStateListener` management methods (`addNodeStateListener`, `removeNodeStateListener`, `clearNodeStateListener`, and `getNodeStateListeners`) utilize a `CopyOnWriteArrayList` for storing listeners. This choice of data structure ensures thread safety for the operations performed on the list of `NodeStateListener` instances, as `CopyOnWriteArrayList` is designed to handle concurrent modifications safely by making a fresh copy of the underlying array upon modification. Thus, the implementation of these methods in the `NodeImpl` class is thread-safe, which aligns with the requirements for concurrent access in a multi-threaded environment like that of SOFAJRaft.--- `418-438`: Consider adding documentation for the default methods in `NodeStateListener` to explain when they should be called and what the expected actions might be.Scripts Executed
The following scripts were executed for the analysis: --- Script: ```shell #!/bin/bash # Verify if the methods are synchronized or if the underlying data structure is thread-safe. rg --type java 'NodeStateListener' -C 10 ``` Length of output: 17157jraft-core/src/main/java/com/alipay/sofa/jraft/core/NodeImpl.java (2)
`2681-2683`: Ensure that the `peerNotInConf` method in the `NodeStateListener` interface handles exceptions gracefully to prevent potential disruptions in the node's operations if a listener implementation throws an exception. --- `3458-3478`: The methods for managing `NodeStateListener` instances (add, remove, clear, get) are implemented correctly. Ensure that these methods are thread-safe if `NodeImpl` instances can be accessed by multiple threads concurrently.Verification successful
--- The methods for managing `NodeStateListener` instances in `NodeImpl` are thread-safe as they utilize a `CopyOnWriteArrayList` for `nodeStateListeners`. This ensures that all modifications and access to the list are handled in a thread-safe manner. Therefore, the implementation aligns with the requirements for thread safety in a concurrent environment.Scripts Executed
The following scripts were executed for the analysis: --- Script: ```shell #!/bin/bash # Check for any additional synchronization mechanisms around nodeStateListeners usage across the codebase. rg --type java "nodeStateListeners" ``` Length of output: 1065
添加节点投票异常监听器，以便为用户提供处理自动加入集群的时机；
Motivation:
在新节点加入集群或历史节点被移除后再次启动加入集群时，由于缺少触发参与集群投票异常的时机，使得无法做自动加入集群处理。当前pr在新加入集群(参与者不在配置中)，或投票提示么有权限(节点被移除后再次启动时)；
对于为什么会出现历史节点移除后再次加入集群。目前出现的原因是，一般系统可能会添加一定心跳时间无法响应时做出自动移除节点(一般是节点下线)，后系统再次回复。
Modification:
在NodeImpl preVote方法配置检查异常时添加peerNotInConf回调方法，处理当前参与者不在配置中(没有加入)；
在NodeImpl handlePreVoteResponse响应提示没有投票权时添加noVotingGranted回调方法，处理当前参与者虽然在本地配置中，但是不在集群配置中，也就是没有投票权(节点被自动移除然后恢复时)。
Summary by CodeRabbit
NodeStateListenerinstances, allowing users to subscribe to specific node state changes.NodeStateListenerinterface for custom handling of node state events.