如何学习raft分布式一致性算法

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raft分布式一致性算法

分布式存储系统通常会通过维护多个副本来进行容错，以提高系统的可用性。这就引出了分布式存储系统的核心问题--如何保证多个副本的一致性？Raft算法把问题分解成了四个子问题：1. 领袖选举（leader election）、2. 日志复制（log replication）、3. 安全性（safety）4. 成员关系变化（membership changes）这几个子问题。源码gitee地址：https://gitee.com/ioly/learning.gooop原文链接：https://my.oschina.net/ioly/blog/5011356

目标

• 根据raft协议，实现高可用分布式强一致的kv存储

子目标（Day 12）

• 终于可以"点火"了，来到这里不容易 _

• 添加大量诊断日志

• 修复若干细节问题

• 编写单元测试代码：

• 启动多个raft节点

• 检测Leader选举是否成功

• 向节点1写入若干数据

• 向节点2写入若干数据

• 在节点3读取数据

• kill掉当前Leader节点，观察重新选举是否成功

单元测试

tRaftKVServer_test.go，在本地启动四个raft节点进行功能性测试

package serverimport (        "learning/gooop/etcd/raft/debug"        "learning/gooop/etcd/raft/logger"        "learning/gooop/etcd/raft/rpc"        "testing"        "time"        nrpc "net/rpc")func Test_RaftKVServer(t *testing.T) {        fnAssertTrue := func(b bool, msg string) {                if !b {                        t.Fatal(msg)                }        }        logger.Exclude("RaftRPCServer.Ping")        logger.Exclude("RaftRPCServer.Heartbeat")        logger.Exclude("feLeaderHeartbeat")        logger.Exclude(").Heartbeat")        // start node 1 to 3        _ = new(tRaftKVServer).BeginServeTCP("./node-01")        _ = new(tRaftKVServer).BeginServeTCP("./node-02")        _ = new(tRaftKVServer).BeginServeTCP("./node-03")        _ = new(tRaftKVServer).BeginServeTCP("./node-04")        // wait for up        time.Sleep(1 * time.Second)        // tRaftLSMImplement(node-01,1).HandleStateChanged, state=2        fnAssertTrue(logger.Count("HandleStateChanged, state=3") == 1, "expecting leader node")        t.Logf("passing electing, leader=%v", debug.LeaderNodeID)        // put into node-1        c1,_ := nrpc.Dial("tcp", "localhost:3331")        defer c1.Close()        kcmd := new(rpc.KVCmd)        kcmd.OPCode = rpc.KVPut        kcmd.Key = []byte("key-01")        kcmd.Content = []byte("content 01")        kret := new(rpc.KVRet)        err := c1.Call("KVStoreRPCServer.ExecuteKVCmd", kcmd, kret)        fnAssertTrue(err == nil && kret.Code == rpc.KVOk, "expecting KVOk")        t.Log("passing put into node-01")        // put into node-2        c2,_ := nrpc.Dial("tcp", "localhost:3332")        defer c2.Close()        kcmd.Key = []byte("key-02")        kcmd.Content = []byte("content 02")        err = c2.Call("KVStoreRPCServer.ExecuteKVCmd", kcmd, kret)        fnAssertTrue(err == nil && kret.Code == rpc.KVOk, "expecting KVOk")        t.Log("passing put into node-02")        // get from node-3        c3,_ := nrpc.Dial("tcp", "localhost:3333")        defer c3.Close()        kcmd.OPCode = rpc.KVGet        kcmd.Key = []byte("key-02")        kcmd.Content = nil        kret.Content = nil        kret.Key = nil        err = c3.Call("KVStoreRPCServer.ExecuteKVCmd", kcmd, kret)        fnAssertTrue(err == nil && kret.Code == rpc.KVOk, "expecting KVOk")        fnAssertTrue(kret.Content != nil && string(kret.Content) == "content 02", "expecting content 02")        t.Log("passing get from node-04")        // kill leader node        debug.KilledNodeID = debug.LeaderNodeID        time.Sleep(2 * time.Second)        fnAssertTrue(logger.Count("HandleStateChanged, state=3") == 2, "expecting reelecting leader node")        t.Logf("passing reelecting, leader=%v", debug.LeaderNodeID)        time.Sleep(2 * time.Second)}

测试输出

可以观察到5个passing，测试ok，重新选举的时延也在预期范围内，约700ms

API server listening at: [::]:46709=== RUN   Test_RaftKVServer16:51:09.329792609 tRaftKVServer.BeginServeTCP, starting node-01, port=333116:51:09.329864584 tBrokenState(from=node-01, to=node-01@localhost:3331).whenStartThenBeginDial16:51:09.329888978 tBrokenState(from=node-01, to=node-02@localhost:3332).whenStartThenBeginDial16:51:09.329903778 tBrokenState(from=node-01, to=node-03@localhost:3333).whenStartThenBeginDial16:51:09.329912231 tBrokenState(from=node-01, to=node-04@localhost:3334).whenStartThenBeginDial16:51:09.329920585 tFollowerState(node-01).init16:51:09.329926372 tFollowerState(node-01).initEventHandlers16:51:09.329941794 tFollowerState(node-01).Start16:51:09.330218761 tRaftKVServer.BeginServeTCP, service ready at port=333116:51:09.330549519 tFollowerState(node-01).whenStartThenBeginWatchLeaderTimeout, begin16:51:09.333852427 tRaftKVServer.BeginServeTCP, starting node-02, port=333216:51:09.333893483 tBrokenState(from=node-02, to=node-01@localhost:3331).whenStartThenBeginDial16:51:09.333925018 tBrokenState(from=node-02, to=node-02@localhost:3332).whenStartThenBeginDial16:51:09.333955573 tBrokenState(from=node-02, to=node-03@localhost:3333).whenStartThenBeginDial16:51:09.33397762 tBrokenState(from=node-02, to=node-04@localhost:3334).whenStartThenBeginDial16:51:09.333990318 tFollowerState(node-02).init16:51:09.333997643 tFollowerState(node-02).initEventHandlers16:51:09.334015293 tFollowerState(node-02).Start16:51:09.334089713 tRaftKVServer.BeginServeTCP, service ready at port=333216:51:09.334290701 tFollowerState(node-02).whenStartThenBeginWatchLeaderTimeout, begin16:51:09.337803901 tRaftKVServer.BeginServeTCP, starting node-03, port=333316:51:09.337842816 tBrokenState(from=node-03, to=node-01@localhost:3331).whenStartThenBeginDial16:51:09.337866444 tBrokenState(from=node-03, to=node-02@localhost:3332).whenStartThenBeginDial16:51:09.337880481 tBrokenState(from=node-03, to=node-03@localhost:3333).whenStartThenBeginDial16:51:09.337893773 tBrokenState(from=node-03, to=node-04@localhost:3334).whenStartThenBeginDial16:51:09.337905184 tFollowerState(node-03).init16:51:09.337912795 tFollowerState(node-03).initEventHandlers16:51:09.337945677 tFollowerState(node-03).Start16:51:09.338027861 tRaftKVServer.BeginServeTCP, service ready at port=333316:51:09.338089164 tFollowerState(node-03).whenStartThenBeginWatchLeaderTimeout, begin16:51:09.341594205 tRaftKVServer.BeginServeTCP, starting node-04, port=333416:51:09.34163547 tBrokenState(from=node-04, to=node-01@localhost:3331).whenStartThenBeginDial16:51:09.341679869 tBrokenState(from=node-04, to=node-02@localhost:3332).whenStartThenBeginDial16:51:09.341694419 tBrokenState(from=node-04, to=node-03@localhost:3333).whenStartThenBeginDial16:51:09.3417269 tBrokenState(from=node-04, to=node-04@localhost:3334).whenStartThenBeginDial16:51:09.341741739 tFollowerState(node-04).init16:51:09.341770267 tFollowerState(node-04).initEventHandlers16:51:09.341793763 tFollowerState(node-04).Start16:51:09.34213956 tRaftKVServer.BeginServeTCP, service ready at port=333416:51:09.342361058 tFollowerState(node-04).whenStartThenBeginWatchLeaderTimeout, begin16:51:09.481747744 tBrokenState(from=node-01, to=node-04@localhost:3334).whenDialOKThenSetConn16:51:09.481770012 tBrokenState(from=node-01, to=node-01@localhost:3331).whenDialOKThenSetConn16:51:09.481771692 tBrokenState(from=node-01, to=node-04@localhost:3334).whenDialOKThenSwitchToConnectedState16:51:09.481791046 tBrokenState(from=node-01, to=node-04@localhost:3334).beDisposing16:51:09.481781787 tBrokenState(from=node-01, to=node-01@localhost:3331).whenDialOKThenSwitchToConnectedState16:51:09.481807689 tBrokenState(from=node-01, to=node-01@localhost:3331).beDisposing16:51:09.481747893 tBrokenState(from=node-01, to=node-02@localhost:3332).whenDialOKThenSetConn16:51:09.481933708 tBrokenState(from=node-01, to=node-02@localhost:3332).whenDialOKThenSwitchToConnectedState16:51:09.481955515 tBrokenState(from=node-01, to=node-02@localhost:3332).beDisposing16:51:09.481747742 tBrokenState(from=node-01, to=node-03@localhost:3333).whenDialOKThenSetConn16:51:09.481973577 tBrokenState(from=node-01, to=node-03@localhost:3333).whenDialOKThenSwitchToConnectedState16:51:09.481980127 tBrokenState(from=node-01, to=node-03@localhost:3333).beDisposing16:51:09.485403927 tBrokenState(from=node-02, to=node-01@localhost:3331).whenDialOKThenSetConn16:51:09.485692968 tBrokenState(from=node-02, to=node-01@localhost:3331).whenDialOKThenSwitchToConnectedState16:51:09.485707781 tBrokenState(from=node-02, to=node-01@localhost:3331).beDisposing16:51:09.485462572 tBrokenState(from=node-02, to=node-02@localhost:3332).whenDialOKThenSetConn16:51:09.485520127 tBrokenState(from=node-02, to=node-03@localhost:3333).whenDialOKThenSetConn16:51:09.485723854 tBrokenState(from=node-02, to=node-02@localhost:3332).whenDialOKThenSwitchToConnectedState16:51:09.485733962 tBrokenState(from=node-02, to=node-02@localhost:3332).beDisposing16:51:09.485733667 tBrokenState(from=node-02, to=node-03@localhost:3333).whenDialOKThenSwitchToConnectedState16:51:09.485749968 tBrokenState(from=node-02, to=node-03@localhost:3333).beDisposing16:51:09.485474638 tBrokenState(from=node-02, to=node-04@localhost:3334).whenDialOKThenSetConn16:51:09.485780798 tBrokenState(from=node-02, to=node-04@localhost:3334).whenDialOKThenSwitchToConnectedState16:51:09.485787997 tBrokenState(from=node-02, to=node-04@localhost:3334).beDisposing16:51:09.489019463 tBrokenState(from=node-03, to=node-02@localhost:3332).whenDialOKThenSetConn16:51:09.489141518 tBrokenState(from=node-03, to=node-02@localhost:3332).whenDialOKThenSwitchToConnectedState16:51:09.489165663 tBrokenState(from=node-03, to=node-02@localhost:3332).beDisposing16:51:09.489021724 tBrokenState(from=node-03, to=node-03@localhost:3333).whenDialOKThenSetConn16:51:09.489191277 tBrokenState(from=node-03, to=node-03@localhost:3333).whenDialOKThenSwitchToConnectedState16:51:09.489199495 tBrokenState(from=node-03, to=node-03@localhost:3333).beDisposing16:51:09.489021727 tBrokenState(from=node-03, to=node-04@localhost:3334).whenDialOKThenSetConn16:51:09.489019621 tBrokenState(from=node-03, to=node-01@localhost:3331).whenDialOKThenSetConn16:51:09.489217044 tBrokenState(from=node-03, to=node-04@localhost:3334).whenDialOKThenSwitchToConnectedState16:51:09.489222223 tBrokenState(from=node-03, to=node-01@localhost:3331).whenDialOKThenSwitchToConnectedState16:51:09.489234054 tBrokenState(from=node-03, to=node-01@localhost:3331).beDisposing16:51:09.489225544 tBrokenState(from=node-03, to=node-04@localhost:3334).beDisposing16:51:09.492701804 tBrokenState(from=node-04, to=node-01@localhost:3331).whenDialOKThenSetConn16:51:09.492720605 tBrokenState(from=node-04, to=node-01@localhost:3331).whenDialOKThenSwitchToConnectedState16:51:09.492728029 tBrokenState(from=node-04, to=node-01@localhost:3331).beDisposing16:51:09.492702391 tBrokenState(from=node-04, to=node-02@localhost:3332).whenDialOKThenSetConn16:51:09.492764 tBrokenState(from=node-04, to=node-02@localhost:3332).whenDialOKThenSwitchToConnectedState16:51:09.492771402 tBrokenState(from=node-04, to=node-02@localhost:3332).beDisposing16:51:09.492778635 tBrokenState(from=node-04, to=node-04@localhost:3334).whenDialOKThenSetConn16:51:09.492791174 tBrokenState(from=node-04, to=node-04@localhost:3334).whenDialOKThenSwitchToConnectedState16:51:09.492799699 tBrokenState(from=node-04, to=node-04@localhost:3334).beDisposing16:51:09.492844734 tBrokenState(from=node-04, to=node-03@localhost:3333).whenDialOKThenSetConn16:51:09.492855638 tBrokenState(from=node-04, to=node-03@localhost:3333).whenDialOKThenSwitchToConnectedState16:51:09.492863777 tBrokenState(from=node-04, to=node-03@localhost:3333).beDisposing16:51:10.238765817 tFollowerState(node-01).whenLeaderHeartbeatTimeoutThenSwitchToCandidateState, term=016:51:10.238808459 tFollowerState(node-01).feDisposing, disposed=true16:51:10.238885964 tRaftLSMImplement(node-01,1).HandleStateChanged, state=216:51:10.238892892 tRaftLSMImplement(node-01,1).meStateChanged, 216:51:10.238897706 tCandidateState(node-01).whenStartThenAskForVote16:51:10.238902038 tCandidateState(node-01).ceAskingForVote, term=116:51:10.238907133 tCandidateState(node-01).ceAskingForVote, vote to myself16:51:10.2389139 tCandidateState(node-01).ceAskingForVote, ticketCount=116:51:10.238920737 tCandidateState(node-01).whenAskingForVoteThenWatchElectionTimeout16:51:10.239208777 tFollowerState(node-04).feCandidateRequestVote, reset last vote16:51:10.239233375 tFollowerState(node-04).feVoteToCandidate, candidate=node-01, term=116:51:10.239261011 tFollowerState(node-02).feCandidateRequestVote, reset last vote16:51:10.239273156 tFollowerState(node-02).feVoteToCandidate, candidate=node-01, term=116:51:10.239288823 tRaftLSMImplement(node-04,1).RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, err=16:51:10.239303552 RaftRPCServer.RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, e=16:51:10.239343533 tRaftLSMImplement(node-02,1).RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, err=16:51:10.239390716 tFollowerState(node-03).feCandidateRequestVote, reset last vote16:51:10.239431327 tFollowerState(node-03).feVoteToCandidate, candidate=node-01, term=116:51:10.239442927 tCandidateState(node-01).handleRequestVoteOK, peer=node-04, term=116:51:10.239455262 tCandidateState(node-01).ceReceiveTicket, mTicketCount=216:51:10.239463079 tCandidateState(node-01).whenReceiveTicketThenCheckTicketCount16:51:10.239473836 tRaftLSMImplement(node-03,1).RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, err=16:51:10.239488078 RaftRPCServer.RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, e=16:51:10.239412948 RaftRPCServer.RequestVote, cmd=&{node-01 1 0 0}, ret=&{0 1}, e=16:51:10.239578689 tCandidateState(node-01).handleRequestVoteOK, peer=node-03, term=116:51:10.239593183 tCandidateState(node-01).ceReceiveTicket, mTicketCount=316:51:10.239601334 tCandidateState(node-01).whenReceiveTicketThenCheckTicketCount16:51:10.239629478 tCandidateState(node-01).whenWinningTheVoteThenSwitchToLeader16:51:10.239639823 tCandidateState(node-01).ceDisposing, mTicketCount=016:51:10.239696198 tCandidateState(node-01).ceDisposing, mDisposedFlag=true16:51:10.239752502 tRaftLSMImplement(node-01,2).HandleStateChanged, state=316:51:10.239764172 tRaftLSMImplement(node-01,2).meStateChanged, 3    tRaftKVServer_test.go:34: passing electing, leader=node-0116:51:10.366875446 tRaftLSMImplement(node-02,1).AppendLog, cmd=&{node-01 1 0xc0004961c0}, ret=&{0 1 0 0}, err=16:51:10.366931566 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc0004961c0}, ret=&{0 1 0 0}, e=16:51:10.370788589 tRaftLSMImplement(node-03,1).AppendLog, cmd=&{node-01 1 0xc00043c5c0}, ret=&{0 1 0 0}, err=16:51:10.370829944 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc00043c5c0}, ret=&{0 1 0 0}, e=16:51:10.374865684 tRaftLSMImplement(node-04,1).AppendLog, cmd=&{node-01 1 0xc000496580}, ret=&{0 1 0 0}, err=16:51:10.374904568 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc000496580}, ret=&{0 1 0 0}, e=16:51:10.375163435 tRaftLSMImplement(node-02,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.375176692 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.375444843 tRaftLSMImplement(node-03,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.375512284 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.375797446 tRaftLSMImplement(node-04,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.375859612 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.379551174 tRaftLSMImplement(node-01,3).ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 49] [99 111 110 116 101 110 116 32 48 49]}, ret=&{0 [] []}, err=16:51:10.379577233 KVStoreRPCServer.ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 49] [99 111 110 116 101 110 116 32 48 49]}, ret=&{0 [] []}, e=    tRaftKVServer_test.go:46: passing put into node-0116:51:10.387761245 tRaftLSMImplement(node-02,1).AppendLog, cmd=&{node-01 1 0xc000496d80}, ret=&{0 1 0 0}, err=16:51:10.387777654 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc000496d80}, ret=&{0 1 0 0}, e=16:51:10.391348874 tRaftLSMImplement(node-03,1).AppendLog, cmd=&{node-01 1 0xc000496e40}, ret=&{0 1 0 0}, err=16:51:10.391387707 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc000496e40}, ret=&{0 1 0 0}, e=16:51:10.395137344 tRaftLSMImplement(node-04,1).AppendLog, cmd=&{node-01 1 0xc000496f00}, ret=&{0 1 0 0}, err=16:51:10.395155304 RaftRPCServer.AppendLog, cmd=&{node-01 1 0xc000496f00}, ret=&{0 1 0 0}, e=16:51:10.395343688 tRaftLSMImplement(node-02,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.395357145 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.395495604 tRaftLSMImplement(node-03,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.3955081 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.395667457 tRaftLSMImplement(node-04,1).CommitLog, cmd=&{node-01 1 1}, ret=&{1}, err=16:51:10.395688067 RaftRPCServer.CommitLog, cmd=&{node-01 1 1}, ret=&{1}, e=16:51:10.399174064 tRaftLSMImplement(node-01,3).ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 50] [99 111 110 116 101 110 116 32 48 50]}, ret=&{0 [] []}, err=16:51:10.399217896 KVStoreRPCServer.ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 50] [99 111 110 116 101 110 116 32 48 50]}, ret=&{0 [] []}, e=16:51:10.399373787 tRaftLSMImplement(node-02,1).ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 50] [99 111 110 116 101 110 116 32 48 50]}, ret=&{0 [] []}, err=16:51:10.399397275 KVStoreRPCServer.ExecuteKVCmd, cmd=&{1 [107 101 121 45 48 50] [99 111 110 116 101 110 116 32 48 50]}, ret=&{0 [] []}, e=    tRaftKVServer_test.go:55: passing put into node-0216:51:10.400256236 tRaftLSMImplement(node-01,3).ExecuteKVCmd, cmd=&{0 [107 101 121 45 48 50] []}, ret=&{0 [] [99 111 110 116 101 110 116 32 48 50]}, err=16:51:10.400298117 KVStoreRPCServer.ExecuteKVCmd, cmd=&{0 [107 101 121 45 48 50] []}, ret=&{0 [] [99 111 110 116 101 110 116 32 48 50]}, e=16:51:10.400639059 tRaftLSMImplement(node-03,1).ExecuteKVCmd, cmd=&{0 [107 101 121 45 48 50] []}, ret=&{0 [] [99 111 110 116 101 110 116 32 48 50]}, err=16:51:10.400663438 KVStoreRPCServer.ExecuteKVCmd, cmd=&{0 [107 101 121 45 48 50] []}, ret=&{0 [] [99 111 110 116 101 110 116 32 48 50]}, e=    tRaftKVServer_test.go:68: passing get from node-0416:51:10.431051964 tRaftKVServer.whenStartThenWatchDebugKill, killing node-012021/04/07 16:51:10 rpc.Serve: accept:accept tcp [::]:3331: use of closed network connection16:51:11.19072568 tFollowerState(node-02).whenLeaderHeartbeatTimeoutThenSwitchToCandidateState, term=116:51:11.190755031 tFollowerState(node-02).feDisposing, disposed=true16:51:11.190856259 tRaftLSMImplement(node-02,1).HandleStateChanged, state=216:51:11.190885201 tRaftLSMImplement(node-02,1).meStateChanged, 216:51:11.190898966 tCandidateState(node-02).whenStartThenAskForVote16:51:11.190908485 tCandidateState(node-02).ceAskingForVote, term=216:51:11.1909172 tCandidateState(node-02).ceAskingForVote, vote to myself16:51:11.19093098 tCandidateState(node-02).ceAskingForVote, ticketCount=116:51:11.190944035 tCandidateState(node-02).whenAskingForVoteThenWatchElectionTimeout16:51:11.191694746 tFollowerState(node-03).feVoteToCandidate, candidate=node-02, term=216:51:11.191724769 tRaftLSMImplement(node-01,3).RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 0}, err=16:51:11.192305012 RaftRPCServer.RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 0}, e=16:51:11.192223342 tFollowerState(node-04).feCandidateRequestVote, reset last vote16:51:11.192464666 tFollowerState(node-04).feVoteToCandidate, candidate=node-02, term=216:51:11.19253627 tRaftLSMImplement(node-04,1).RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 2}, err=16:51:11.192208542 tRaftLSMImplement(node-03,1).RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 2}, err=16:51:11.192613581 tCandidateState(node-02).handleRequestVoteOK, peer=node-01, term=216:51:11.192627483 tCandidateState(node-02).ceReceiveTicket, mTicketCount=216:51:11.192634994 tCandidateState(node-02).whenReceiveTicketThenCheckTicketCount16:51:11.19260158 RaftRPCServer.RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 2}, e=16:51:11.192764937 tCandidateState(node-02).handleRequestVoteOK, peer=node-03, term=216:51:11.192778197 tCandidateState(node-02).ceReceiveTicket, mTicketCount=316:51:11.192784986 tCandidateState(node-02).whenReceiveTicketThenCheckTicketCount16:51:11.192806525 tCandidateState(node-02).whenWinningTheVoteThenSwitchToLeader16:51:11.192815315 tCandidateState(node-02).ceDisposing, mTicketCount=016:51:11.192836837 tCandidateState(node-02).ceDisposing, mDisposedFlag=true16:51:11.192853274 tRaftLSMImplement(node-02,2).HandleStateChanged, state=316:51:11.192863098 tRaftLSMImplement(node-02,2).meStateChanged, 316:51:11.193007386 tFollowerState(node-01).init16:51:11.193017792 tFollowerState(node-01).initEventHandlers16:51:11.193037127 tRaftLSMImplement(node-01,3).HandleStateChanged, state=116:51:11.193046674 tRaftLSMImplement(node-01,3).meStateChanged, 116:51:11.193053504 tFollowerState(node-01).Start16:51:11.19313721 tFollowerState(node-01).whenStartThenBeginWatchLeaderTimeout, begin16:51:11.192549822 RaftRPCServer.RequestVote, cmd=&{node-02 2 0 0}, ret=&{0 2}, e=    tRaftKVServer_test.go:74: passing reelecting, leader=node-02--- PASS: Test_RaftKVServer (5.09s)PASSDebugger finished with exit code 0

debug.go

支持单元测试的上下文变量

package debug// KilledNodeID was used to detect whether a node should stop wroking, written by unit test codevar KilledNodeID = ""// LeaderNodeID presents current leader node's ID, written by lsm/tLeaderStatevar LeaderNodeID = ""

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