@Override
public void run() {
try {
while (!finished) {
Request request = queuedRequests.take();
if (LOG.isTraceEnabled()) {
ZooTrace.logRequest(LOG, ZooTrace.CLIENT_REQUEST_TRACE_MASK, 'F', request, "");
}
if (request == Request.requestOfDeath) {
break;
}
// We want to queue the request to be processed before we submit
// the request to the leader so that we are ready to receive
// the response
nextProcessor.processRequest(request);
// We now ship the request to the leader. As with all
// other quorum operations, sync also follows this code
// path, but different from others, we need to keep track
// of the sync operations this Observer has pending, so we
// add it to pendingSyncs.
switch (request.type) {
case OpCode.sync:
zks.pendingSyncs.add(request);
zks.getObserver().request(request);
break;
case OpCode.create:
case OpCode.create2:
case OpCode.delete:
case OpCode.setData:
case OpCode.reconfig:
case OpCode.setACL:
case OpCode.multi:
case OpCode.check:
zks.getObserver().request(request);
break;
case OpCode.createSession:
case OpCode.closeSession:
// Don't forward local sessions to the leader.
if (!request.isLocalSession()) {
zks.getObserver().request(request);
}
break;
}
}
} catch (Exception e) {
LOG.error("Unexpected exception causing exit", e);
}
LOG.info("ObserverRequestProcessor exited loop!");
}
/** Simply queue the request, which will be processed in FIFO order. */
public void processRequest(Request request) {
if (!finished) {
Request upgradeRequest = null;
try {
upgradeRequest = zks.checkUpgradeSession(request);
} catch (KeeperException ke) {
if (request.getHdr() != null) {
request.getHdr().setType(OpCode.error);
request.setTxn(new ErrorTxn(ke.code().intValue()));
}
request.setException(ke);
LOG.info("Error creating upgrade request", ke);
} catch (IOException ie) {
LOG.error("Unexpected error in upgrade", ie);
}
if (upgradeRequest != null) {
queuedRequests.add(upgradeRequest);
}
queuedRequests.add(request);
}
}
/**
* Constructor - takes an ObserverZooKeeperServer to associate with and the next processor to pass
* requests to after we're finished.
*
* @param zks
* @param nextProcessor
*/
public ObserverRequestProcessor(ObserverZooKeeperServer zks, RequestProcessor nextProcessor) {
super("ObserverRequestProcessor:" + zks.getServerId());
this.zks = zks;
this.nextProcessor = nextProcessor;
}