func testCM_SOLO_Follower_ElectsSelfOnElectionTimeout(
t *testing.T,
mcm *managedConsensusModule,
mrs *testhelpers.MockRpcSender,
) {
if mcm.pcm.GetServerState() != FOLLOWER {
t.Fatal()
}
if mcm.pcm.RaftPersistentState.GetVotedFor() != "" {
t.Fatal()
}
// Test that a tick before election timeout causes no state change.
err := mcm.Tick()
if err != nil {
t.Fatal(err)
}
if mcm.pcm.RaftPersistentState.GetCurrentTerm() != testdata.CurrentTerm {
t.Fatal()
}
if mcm.pcm.GetServerState() != FOLLOWER {
t.Fatal()
}
var expectedNewTerm TermNo = testdata.CurrentTerm + 1
timeout1 := mcm.pcm.ElectionTimeoutTracker.GetCurrentElectionTimeout()
// Test that election timeout causes a new election
mcm.tickTilElectionTimeout(t)
if mcm.pcm.RaftPersistentState.GetCurrentTerm() != expectedNewTerm {
t.Fatal(expectedNewTerm, mcm.pcm.RaftPersistentState.GetCurrentTerm())
}
// Single node should immediately elect itself as leader
if mcm.pcm.GetServerState() != LEADER {
t.Fatal()
}
// candidate has voted for itself
if mcm.pcm.RaftPersistentState.GetVotedFor() != testdata.ThisServerId {
t.Fatal()
}
// a new election timeout was chosen
if mcm.pcm.ElectionTimeoutTracker.GetCurrentElectionTimeout() == timeout1 {
t.Fatal()
}
// candidate state is fresh
expectedCvs, err := consensus_state.NewCandidateVolatileState(mcm.pcm.ClusterInfo)
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(mcm.pcm.CandidateVolatileState, expectedCvs) {
t.Fatal()
}
// no RPCs issued
mrs.CheckSentRpcs(t, make(map[ServerId]interface{}))
mrs.ClearSentRpcs()
}
func testCM_FollowerOrCandidate_StartsElectionOnElectionTimeout_Part2(
t *testing.T,
mcm *managedConsensusModule,
mrs *testhelpers.MockRpcSender,
expectedNewTerm TermNo,
) {
timeout1 := mcm.pcm.ElectionTimeoutTracker.GetCurrentElectionTimeout()
// Test that election timeout causes a new election
mcm.tickTilElectionTimeout(t)
if mcm.pcm.RaftPersistentState.GetCurrentTerm() != expectedNewTerm {
t.Fatal(expectedNewTerm, mcm.pcm.RaftPersistentState.GetCurrentTerm())
}
if mcm.pcm.GetServerState() != CANDIDATE {
t.Fatal()
}
// candidate has voted for itself
if mcm.pcm.RaftPersistentState.GetVotedFor() != testdata.ThisServerId {
t.Fatal()
}
// a new election timeout was chosen
// Playing the odds here :P
if mcm.pcm.ElectionTimeoutTracker.GetCurrentElectionTimeout() == timeout1 {
t.Fatal()
}
// candidate state is fresh
expectedCvs, err := consensus_state.NewCandidateVolatileState(mcm.pcm.ClusterInfo)
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(mcm.pcm.CandidateVolatileState, expectedCvs) {
t.Fatal()
}
// candidate has issued RequestVote RPCs to all other servers.
lastLogIndex, lastLogTerm, err := GetIndexAndTermOfLastEntry(mcm.pcm.LogRO)
if err != nil {
t.Fatal(err)
}
expectedRpc := &RpcRequestVote{expectedNewTerm, lastLogIndex, lastLogTerm}
expectedRpcs := map[ServerId]interface{}{}
err = mcm.pcm.ClusterInfo.ForEachPeer(func(serverId ServerId) error {
expectedRpcs[serverId] = expectedRpc
return nil
})
if err != nil {
t.Fatal(err)
}
mrs.CheckSentRpcs(t, expectedRpcs)
mrs.ClearSentRpcs()
}
func (cm *PassiveConsensusModule) becomeCandidateAndBeginElection(now time.Time) error {
// #RFS-C1: On conversion to candidate, start election:
// Increment currentTerm; Vote for self; Send RequestVote RPCs
// to all other servers; Reset election timer
// #5.2-p2s1: To begin an election, a follower increments its
// current term and transitions to candidate state.
newTerm := cm.RaftPersistentState.GetCurrentTerm() + 1
err := cm.RaftPersistentState.SetCurrentTerm(newTerm)
if err != nil {
return err
}
cm.CandidateVolatileState, err = consensus_state.NewCandidateVolatileState(cm.ClusterInfo)
if err != nil {
return err
}
cm.setServerState(CANDIDATE)
// #5.2-p2s2: It then votes for itself and issues RequestVote RPCs
// in parallel to each of the other servers in the cluster.
err = cm.RaftPersistentState.SetVotedFor(cm.ClusterInfo.GetThisServerId())
if err != nil {
return err
}
lastLogIndex, lastLogTerm, err := GetIndexAndTermOfLastEntry(cm.LogRO)
if err != nil {
return err
}
err = cm.ClusterInfo.ForEachPeer(
func(serverId ServerId) error {
rpcRequestVote := &RpcRequestVote{newTerm, lastLogIndex, lastLogTerm}
cm.RpcSendOnly.SendOnlyRpcRequestVoteAsync(serverId, rpcRequestVote)
return nil
},
)
if err != nil {
return err
}
// Reset election timeout!
cm.ElectionTimeoutTracker.ChooseNewRandomElectionTimeoutAndTouch(now)
return nil
}