void
ReplicatorStateMachine::inLeaderStateHandler( )
{
dprintf( D_ALWAYS, "ReplicatorStateMachine::inLeaderStateHandler started "
"with state = %d\n", int( m_state ) );
// REPLICATION_ASSERT(m_state != BACKUP)
if( m_state == VERSION_REQUESTING || m_state == VERSION_DOWNLOADING) {
return ;
}
// receiving this notification message in BACKUP state means, that the
// pool version downloading took more time than it took for the HAD to
// become active, in this case we act as if we received AFTER_ELECTION
// message
if( m_state == BACKUP ) {
becomeLeader( );
return ;
}
m_lastHadAliveTime = time( NULL );
dprintf( D_FULLDEBUG,
"ReplicatorStateMachine::inLeaderStateHandler last HAD alive time "
"is set to %s", ctime( &m_lastHadAliveTime ) );
//if( downloadTransferersNumber( ) == 0 &&
// replicaSelectionHandler( newVersion ) ) {
// download( newVersion.getSinfulString( ).Value( ) );
//}
}
void RaftConsensus::becomeCandidate() {
std::cout << "RaftState: become candidate" << std::endl;
state_ = StateCandidate;
votes_ = 0;
// 删除心跳定时器
removeHeartbeatTimer();
// 开启选举超时定时器
resetElectionTimer();
++term_; // term + 1
++votes_; // 给自己投票
if (votes_ >= majority_)
becomeLeader();
VoteRequest req;
req.set_term(term_);
req.set_candidateid(id_);
req.set_lastlogterm(0); //TODO: set logger
req.set_lastlogindex(0);
for (auto& kv: peers_) {
auto stub = rpc_stubs_->getStub(kv.first);
if (stub) {
stub->RequesetVoteAsync(
req,
std::bind(&RaftConsensus::handleVoteResponse, this, term_, std::placeholders::_1, std::placeholders::_2),
1000
);
}
}
}
void
ReplicatorStateMachine::afterElectionStateHandler()
{
dprintf( D_ALWAYS, "ReplicatorStateMachine::afterElectionStateHandler "
"started\n" );
REPLICATION_ASSERT(m_state != REPLICATION_LEADER);
// we stay in VERSION_REQUESTING or VERSION_DOWNLOADING state
// of newly joining node, we will go to LEADER_STATE later
// upon receiving of IN_LEADER message from HAD
if( m_state == VERSION_REQUESTING || m_state == VERSION_DOWNLOADING ) {
return ;
}
becomeLeader( );
}
// src_term: 本地发起投票请求时当时本地的term
void RaftConsensus::handleVoteResponse(uint64_t src_term, const VoteResponse& resp, const grpc::Status& status) {
if (!status.ok() && status.error_code() != grpc::StatusCode::CANCELLED) {
std::cerr << "RequestVote RPC failed: " << status.error_message() << std::endl;
return;
}
std::lock_guard<std::mutex> lock(mu_);
if (src_term != term_) {
std::cout << "Mismatched term in VoteResponse:" << src_term <<
", cur:" << term_ << std::endl;
return;
}
else if (StateCandidate == state_) {
if (resp.votegranted()) {
++votes_;
if (votes_ >= majority_)
becomeLeader();
}
}
//TODO
}