/*
* (non-Javadoc)
*
* @see poke.server.election.Election#process(eye.Comm.LeaderElection)
*
* @return The Management instance returned represents the message to send
* on. If null, no action is required. Not a great choice to convey to the
* caller; can be improved upon easily.
*/
@Override
public Management process(Management mgmt) {
if (!mgmt.hasElection()) return null;
LeaderElection req = mgmt.getElection();
if (req.getExpires() <= System.currentTimeMillis()) {
// election has expired without a conclusion?
}
Management rtn = null;
if (req.getAction().getNumber() == ElectAction.DECLAREELECTION_VALUE) {
// an election is declared!
// required to eliminate duplicate messages - on a declaration,
// should not happen if the network does not have cycles
List<VectorClock> rtes = mgmt.getHeader().getPathList();
for (VectorClock rp : rtes) {
if (rp.getNodeId() == this.nodeId) {
// message has already been sent to me, don't use and
// forward
return null;
}
}
// I got here because the election is unknown to me
// this 'if debug is on' should cover the below dozen or so
// println()s. It is here to help with seeing when an election
// occurs.
if (logger.isDebugEnabled()) {}
System.out.println("\n\n*********************************************************");
System.out.println(" RAFT ELECTION: Election declared");
System.out.println(" Election ID: " + req.getElectId());
System.out.println(" Rcv from: Node " + mgmt.getHeader().getOriginator());
System.out.println(" Expires: " + new Date(req.getExpires()));
System.out.println(" Nominates: Node " + req.getCandidateId());
System.out.println(" Desc: " + req.getDesc());
System.out.print(" Routing tbl: [");
for (VectorClock rp : rtes)
System.out.print(
"Node " + rp.getNodeId() + " (" + rp.getVersion() + "," + rp.getTime() + "), ");
System.out.println("]");
System.out.println("*********************************************************\n\n");
// sync master IDs to current election
ElectionIDGenerator.setMasterID(req.getElectId());
/**
* a new election can be declared over an existing election.
*
* <p>TODO need to have an monotonically increasing ID that we can test
*/
boolean isNew = updateCurrent(req);
rtn = castVote(mgmt, isNew);
} else if (req.getAction().getNumber() == ElectAction.DECLAREVOID_VALUE) {
// no one was elected, I am dropping into standby mode
logger.info("TODO: no one was elected, I am dropping into standby mode");
this.clear();
notify(false, null);
} else if (req.getAction().getNumber() == ElectAction.DECLAREWINNER_VALUE) {
// some node declared itself the leader
logger.info(
"Election "
+ req.getElectId()
+ ": Node "
+ req.getCandidateId()
+ " is declared the leader");
updateCurrent(mgmt.getElection());
current.active = false; // it's over
notify(true, req.getCandidateId());
} else if (req.getAction().getNumber() == ElectAction.ABSTAIN_VALUE) {
// for some reason, a node declines to vote - therefore, do nothing
} else if (req.getAction().getNumber() == ElectAction.NOMINATE_VALUE) {
boolean isNew = updateCurrent(mgmt.getElection());
rtn = castVote(mgmt, isNew);
} else {
// this is me!
}
return rtn;
}
@Override
public Integer createElectionID() {
return ElectionIDGenerator.nextID();
}
