## 测试
这些测试全面覆盖了Raft算法的核心功能，包括领导选举、日志复制、持久化、恢复、快照等，并在各种网络条件（可靠、不可靠）和故障情况（节点崩溃、网络分区）下进行测试，以确保算法的正确性和鲁棒性。
这些测试涵盖了Raft算法的多个关键方面。我将总结主要的测试类别和它们测试的具体内容:
领导选举 (2A)
TestInitialElection2A: 测试初始选举是否能成功选出一个领导者
TestReElection2A: 测试网络故障后是否能重新选举领导者
TestManyElections2A: 测试在多次网络分区和重连后的选举
基本一致性和日志复制 (2B)
TestBasicAgree2B: 测试基本的日志复制和提交
TestRPCBytes2B: 检查RPC通信效率
TestFailAgree2B: 测试部分节点断开连接时的一致性
TestFailNoAgree2B: 测试多数节点断开时无法达成一致
TestConcurrentStarts2B: 测试并发的日志条目提交
TestRejoin2B: 测试分区后重新加入的节点行为
TestBackup2B: 测试领导者如何处理落后的跟随者日志
TestCount2B: 检查RPC调用次数是否合理
持久化和恢复 (2C)
TestPersist12C, TestPersist22C, TestPersist32C: 测试不同场景下的持久化和恢复
TestFigure82C: 模拟论文图8描述的复杂场景
TestUnreliableAgree2C: 在不可靠网络下测试一致性
TestFigure8Unreliable2C: 在不可靠网络下模拟图8场景
TestReliableChurn2C, TestUnreliableChurn2C: 测试频繁的配置变更
快照 (2D)
TestSnapshotBasic2D: 测试基本的快照功能
TestSnapshotInstall2D: 测试安装快照（网络断开情况）
TestSnapshotInstallUnreliable2D: 测试不可靠网络下安装快照
TestSnapshotInstallCrash2D: 测试节点崩溃时的快照安装
TestSnapshotInstallUnCrash2D: 测试不可靠网络和节点崩溃下的快照安装
## 测试思路
### 1. cfg
- 创建多个 Raft 节点实例
- 控制节点间的通信（可以模拟网络分区、延迟等）
- 启动和停止节点
- 检查节点的状态（如谁是领导者，当前的任期等）
- 模拟客户端请求
- 验证一致性和正确性
## 自己的测试结果
```Java
=== RUN TestInitialElection2A
Test (2A): initial election ...
... Passed -- 4.0 3 48 13764 0
--- PASS: TestInitialElection2A (4.03s)
=== RUN TestReElection2A
Test (2A): election after network failure ...
... Passed -- 6.6 3 108 22958 0
--- PASS: TestReElection2A (6.59s)
=== RUN TestManyElections2A
Test (2A): multiple elections ...
... Passed -- 7.0 7 346 79044 0
--- PASS: TestManyElections2A (6.98s)
=== RUN TestBasicAgree2B
Test (2B): basic agreement ...
... Passed -- 1.5 3 16 4586 3
--- PASS: TestBasicAgree2B (1.47s)
=== RUN TestRPCBytes2B
Test (2B): RPC byte count ...
... Passed -- 2.9 3 48 114550 11
--- PASS: TestRPCBytes2B (2.90s)
=== RUN TestFailAgree2B
Test (2B): agreement despite follower disconnection ...
... Passed -- 7.0 3 80 22341 8
--- PASS: TestFailAgree2B (6.96s)
=== RUN TestFailNoAgree2B
Test (2B): no agreement if too many followers disconnect ...
... Passed -- 4.3 5 125 29716 3
--- PASS: TestFailNoAgree2B (4.27s)
=== RUN TestConcurrentStarts2B
Test (2B): concurrent Start()s ...
... Passed -- 1.5 3 12 3438 6
--- PASS: TestConcurrentStarts2B (1.53s)
=== RUN TestRejoin2B
Test (2B): rejoin of partitioned leader ...
... Passed -- 6.5 3 127 30687 4
--- PASS: TestRejoin2B (6.50s)
=== RUN TestBackup2B
Test (2B): leader backs up quickly over incorrect follower logs ...
... Passed -- 21.5 5 1388 1126823 102
--- PASS: TestBackup2B (21.53s)
=== RUN TestCount2B
Test (2B): RPC counts aren't too high ...
... Passed -- 3.2 3 38 11397 12
--- PASS: TestCount2B (3.20s)
=== RUN TestPersist12C
Test (2C): basic persistence ...
... Passed -- 7.5 3 99 24361 6
--- PASS: TestPersist12C (7.50s)
=== RUN TestPersist22C
Test (2C): more persistence ...
... Passed -- 21.9 5 900 202916 16
--- PASS: TestPersist22C (21.88s)
=== RUN TestPersist32C
Test (2C): partitioned leader and one follower crash, leader restarts ...
... Passed -- 3.1 3 33 8347 4
--- PASS: TestPersist32C (3.15s)
=== RUN TestFigure82C
Test (2C): Figure 8 ...
... Passed -- 30.9 5 437 96545 20
--- PASS: TestFigure82C (30.94s)
=== RUN TestUnreliableAgree2C
Test (2C): unreliable agreement ...
... Passed -- 3.6 5 368 125743 246
--- PASS: TestUnreliableAgree2C (3.63s)
=== RUN TestFigure8Unreliable2C
Test (2C): Figure 8 (unreliable) ...
... Passed -- 31.8 5 2029 5839715 42
--- PASS: TestFigure8Unreliable2C (31.79s)
=== RUN TestReliableChurn2C
Test (2C): churn ...
... Passed -- 16.7 5 5143 5749212 3067
--- PASS: TestReliableChurn2C (16.70s)
=== RUN TestUnreliableChurn2C
Test (2C): unreliable churn ...
... Passed -- 16.2 5 1257 1044671 489
--- PASS: TestUnreliableChurn2C (16.15s)
=== RUN TestSnapshotBasic2D
Test (2D): snapshots basic ...
... Passed -- 5.7 3 179 65036 251
--- PASS: TestSnapshotBasic2D (5.73s)
=== RUN TestSnapshotInstall2D
Test (2D): install snapshots (disconnect) ...
... Passed -- 54.3 3 1046 287884 388
--- PASS: TestSnapshotInstall2D (54.34s)
=== RUN TestSnapshotInstallUnreliable2D
Test (2D): install snapshots (disconnect+unreliable) ...
... Passed -- 59.8 3 1179 307241 366
--- PASS: TestSnapshotInstallUnreliable2D (59.83s)
=== RUN TestSnapshotInstallCrash2D
Test (2D): install snapshots (crash) ...
... Passed -- 46.4 3 702 198750 399
--- PASS: TestSnapshotInstallCrash2D (46.39s)
=== RUN TestSnapshotInstallUnCrash2D
Test (2D): install snapshots (unreliable+crash) ...
... Passed -- 49.0 3 760 205531 355
--- PASS: TestSnapshotInstallUnCrash2D (49.02s)
PASS
```
这些测试涵盖了Raft算法的多个关键方面。我将总结主要的测试类别和它们测试的具体内容:
1. 领导选举 (2A)
- TestInitialElection2A: 测试初始选举是否能成功选出一个领导者
- TestReElection2A: 测试网络故障后是否能重新选举领导者
- TestManyElections2A: 测试在多次网络分区和重连后的选举
2. 基本一致性和日志复制 (2B)
- TestBasicAgree2B: 测试基本的日志复制和提交
- TestRPCBytes2B: 检查RPC通信效率
- TestFailAgree2B: 测试部分节点断开连接时的一致性
- TestFailNoAgree2B: 测试多数节点断开时无法达成一致
- TestConcurrentStarts2B: 测试并发的日志条目提交
- TestRejoin2B: 测试分区后重新加入的节点行为
- TestBackup2B: 测试领导者如何处理落后的跟随者日志
- TestCount2B: 检查RPC调用次数是否合理
3. 持久化和恢复 (2C)
- TestPersist12C, TestPersist22C, TestPersist32C: 测试不同场景下的持久化和恢复
- TestFigure82C: 模拟论文图8描述的复杂场景
- TestUnreliableAgree2C: 在不可靠网络下测试一致性
- TestFigure8Unreliable2C: 在不可靠网络下模拟图8场景
- TestReliableChurn2C, TestUnreliableChurn2C: 测试频繁的配置变更
4. 快照 (2D)
- TestSnapshotBasic2D: 测试基本的快照功能
- TestSnapshotInstall2D: 测试安装快照（网络断开情况）
- TestSnapshotInstallUnreliable2D: 测试不可靠网络下安装快照
- TestSnapshotInstallCrash2D: 测试节点崩溃时的快照安装
- TestSnapshotInstallUnCrash2D: 测试不可靠网络和节点崩溃下的快照安装