import static java.util.Objects.requireNonNull;
import com.google.common.base.MoreObjects;
+import com.google.common.base.MoreObjects.ToStringHelper;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
*
* @author Robert Varga
*/
-final class LeaderFrontendState implements Identifiable<ClientIdentifier> {
- private static final Logger LOG = LoggerFactory.getLogger(LeaderFrontendState.class);
+abstract class LeaderFrontendState implements Identifiable<ClientIdentifier> {
+ static final class Disabled extends LeaderFrontendState {
+ Disabled(final String persistenceId, final ClientIdentifier clientId, final ShardDataTree tree) {
+ super(persistenceId, clientId, tree);
+ }
+
+ @Override
+ LocalHistorySuccess handleLocalHistoryRequest(final LocalHistoryRequest<?> request,
+ final RequestEnvelope envelope, final long now) throws RequestException {
+ throw new UnsupportedRequestException(request);
+ }
+
+ @Override
+ TransactionSuccess<?> handleTransactionRequest(final TransactionRequest<?> request,
+ final RequestEnvelope envelope, final long now) throws RequestException {
+ throw new UnsupportedRequestException(request);
+ }
+ }
+
+ static final class Enabled extends LeaderFrontendState {
+ // Histories which have not been purged
+ private final Map<LocalHistoryIdentifier, LocalFrontendHistory> localHistories;
+
+ // RangeSet performs automatic merging, hence we keep minimal state tracking information
+ private final UnsignedLongRangeSet purgedHistories;
+
+ // Used for all standalone transactions
+ private final AbstractFrontendHistory standaloneHistory;
+
+ private long expectedTxSequence;
+ private Long lastSeenHistory = null;
+
+ Enabled(final String persistenceId, final ClientIdentifier clientId, final ShardDataTree tree) {
+ this(persistenceId, clientId, tree, UnsignedLongRangeSet.create(),
+ StandaloneFrontendHistory.create(persistenceId, clientId, tree), new HashMap<>());
+ }
+
+ Enabled(final String persistenceId, final ClientIdentifier clientId, final ShardDataTree tree,
+ final UnsignedLongRangeSet purgedHistories, final AbstractFrontendHistory standaloneHistory,
+ final Map<LocalHistoryIdentifier, LocalFrontendHistory> localHistories) {
+ super(persistenceId, clientId, tree);
+ this.purgedHistories = requireNonNull(purgedHistories);
+ this.standaloneHistory = requireNonNull(standaloneHistory);
+ this.localHistories = requireNonNull(localHistories);
+ }
+
+ @Override
+ @Nullable LocalHistorySuccess handleLocalHistoryRequest(final LocalHistoryRequest<?> request,
+ final RequestEnvelope envelope, final long now) throws RequestException {
+ checkRequestSequence(envelope);
+
+ try {
+ if (request instanceof CreateLocalHistoryRequest) {
+ return handleCreateHistory((CreateLocalHistoryRequest) request, envelope, now);
+ } else if (request instanceof DestroyLocalHistoryRequest) {
+ return handleDestroyHistory((DestroyLocalHistoryRequest) request, envelope, now);
+ } else if (request instanceof PurgeLocalHistoryRequest) {
+ return handlePurgeHistory((PurgeLocalHistoryRequest)request, envelope, now);
+ } else {
+ LOG.warn("{}: rejecting unsupported request {}", persistenceId(), request);
+ throw new UnsupportedRequestException(request);
+ }
+ } finally {
+ expectNextRequest();
+ }
+ }
+
+ @Override
+ @Nullable TransactionSuccess<?> handleTransactionRequest(final TransactionRequest<?> request,
+ final RequestEnvelope envelope, final long now) throws RequestException {
+ checkRequestSequence(envelope);
+
+ try {
+ final LocalHistoryIdentifier lhId = request.getTarget().getHistoryId();
+ final AbstractFrontendHistory history;
+
+ if (lhId.getHistoryId() != 0) {
+ history = localHistories.get(lhId);
+ if (history == null) {
+ if (purgedHistories.contains(lhId.getHistoryId())) {
+ LOG.warn("{}: rejecting request {} to purged history", persistenceId(), request);
+ throw new DeadHistoryException(purgedHistories.toImmutable());
+ }
+
+ LOG.warn("{}: rejecting unknown history request {}", persistenceId(), request);
+ throw new UnknownHistoryException(lastSeenHistory);
+ }
+ } else {
+ history = standaloneHistory;
+ }
+
+ return history.handleTransactionRequest(request, envelope, now);
+ } finally {
+ expectNextRequest();
+ }
+ }
+
+ @Override
+ void reconnect() {
+ expectedTxSequence = 0;
+ super.reconnect();
+ }
+
+ @Override
+ void retire() {
+ super.retire();
+
+ // Clear out all transaction chains
+ localHistories.values().forEach(AbstractFrontendHistory::retire);
+ localHistories.clear();
+ standaloneHistory.retire();
+ }
+
+ @Override
+ ToStringHelper addToStringAttributes(final ToStringHelper helper) {
+ return super.addToStringAttributes(helper).add("purgedHistories", purgedHistories);
+ }
+
+ private LocalHistorySuccess handleCreateHistory(final CreateLocalHistoryRequest request,
+ final RequestEnvelope envelope, final long now) throws RequestException {
+ final LocalHistoryIdentifier historyId = request.getTarget();
+ final AbstractFrontendHistory existing = localHistories.get(historyId);
+ if (existing != null) {
+ // History already exists: report success
+ LOG.debug("{}: history {} already exists", persistenceId(), historyId);
+ return new LocalHistorySuccess(historyId, request.getSequence());
+ }
+
+ // We have not found the history. Before we create it we need to check history ID sequencing so that we do
+ // not end up resurrecting a purged history.
+ if (purgedHistories.contains(historyId.getHistoryId())) {
+ LOG.debug("{}: rejecting purged request {}", persistenceId(), request);
+ throw new DeadHistoryException(purgedHistories.toImmutable());
+ }
+
+ // Update last history we have seen
+ if (lastSeenHistory == null || Long.compareUnsigned(lastSeenHistory, historyId.getHistoryId()) < 0) {
+ lastSeenHistory = historyId.getHistoryId();
+ }
+
+ // We have to send the response only after persistence has completed
+ final ShardDataTreeTransactionChain chain = tree().ensureTransactionChain(historyId, () -> {
+ LOG.debug("{}: persisted history {}", persistenceId(), historyId);
+ envelope.sendSuccess(new LocalHistorySuccess(historyId, request.getSequence()),
+ tree().readTime() - now);
+ });
+
+ localHistories.put(historyId, LocalFrontendHistory.create(persistenceId(), tree(), chain));
+ LOG.debug("{}: created history {}", persistenceId(), historyId);
+ return null;
+ }
+
+ private LocalHistorySuccess handleDestroyHistory(final DestroyLocalHistoryRequest request,
+ final RequestEnvelope envelope, final long now) {
+ final LocalHistoryIdentifier id = request.getTarget();
+ final LocalFrontendHistory existing = localHistories.get(id);
+ if (existing == null) {
+ // History does not exist: report success
+ LOG.debug("{}: history {} does not exist, nothing to destroy", persistenceId(), id);
+ return new LocalHistorySuccess(id, request.getSequence());
+ }
+
+ existing.destroy(request.getSequence(), envelope, now);
+ return null;
+ }
+
+ private LocalHistorySuccess handlePurgeHistory(final PurgeLocalHistoryRequest request,
+ final RequestEnvelope envelope, final long now) {
+ final LocalHistoryIdentifier id = request.getTarget();
+ final LocalFrontendHistory existing = localHistories.remove(id);
+ if (existing == null) {
+ LOG.debug("{}: history {} has already been purged", persistenceId(), id);
+ return new LocalHistorySuccess(id, request.getSequence());
+ }
+
+ LOG.debug("{}: purging history {}", persistenceId(), id);
+ purgedHistories.add(id.getHistoryId());
+ existing.purge(request.getSequence(), envelope, now);
+ return null;
+ }
+
+ private void checkRequestSequence(final RequestEnvelope envelope) throws OutOfSequenceEnvelopeException {
+ if (expectedTxSequence != envelope.getTxSequence()) {
+ throw new OutOfSequenceEnvelopeException(expectedTxSequence);
+ }
+ }
- // Histories which have not been purged
- private final Map<LocalHistoryIdentifier, LocalFrontendHistory> localHistories;
+ private void expectNextRequest() {
+ expectedTxSequence++;
+ }
+ }
- // RangeSet performs automatic merging, hence we keep minimal state tracking information
- private final UnsignedLongRangeSet purgedHistories;
+ private static final Logger LOG = LoggerFactory.getLogger(LeaderFrontendState.class);
- // Used for all standalone transactions
- private final AbstractFrontendHistory standaloneHistory;
private final ShardDataTree tree;
private final ClientIdentifier clientId;
private final String persistenceId;
private long lastConnectTicks;
private long lastSeenTicks;
- private long expectedTxSequence;
- private Long lastSeenHistory = null;
// TODO: explicit failover notification
// Record the ActorRef for the originating actor and when we switch to being a leader send a notification
// - per-RequestException throw counters
LeaderFrontendState(final String persistenceId, final ClientIdentifier clientId, final ShardDataTree tree) {
- this(persistenceId, clientId, tree, UnsignedLongRangeSet.create(),
- StandaloneFrontendHistory.create(persistenceId, clientId, tree), new HashMap<>());
- }
-
- LeaderFrontendState(final String persistenceId, final ClientIdentifier clientId, final ShardDataTree tree,
- final UnsignedLongRangeSet purgedHistories, final AbstractFrontendHistory standaloneHistory,
- final Map<LocalHistoryIdentifier, LocalFrontendHistory> localHistories) {
this.persistenceId = requireNonNull(persistenceId);
this.clientId = requireNonNull(clientId);
this.tree = requireNonNull(tree);
- this.purgedHistories = requireNonNull(purgedHistories);
- this.standaloneHistory = requireNonNull(standaloneHistory);
- this.localHistories = requireNonNull(localHistories);
this.lastSeenTicks = tree.readTime();
}
@Override
- public ClientIdentifier getIdentifier() {
+ public final ClientIdentifier getIdentifier() {
return clientId;
}
- private void checkRequestSequence(final RequestEnvelope envelope) throws OutOfSequenceEnvelopeException {
- if (expectedTxSequence != envelope.getTxSequence()) {
- throw new OutOfSequenceEnvelopeException(expectedTxSequence);
- }
- }
-
- private void expectNextRequest() {
- expectedTxSequence++;
+ final String persistenceId() {
+ return persistenceId;
}
- @Nullable LocalHistorySuccess handleLocalHistoryRequest(final LocalHistoryRequest<?> request,
- final RequestEnvelope envelope, final long now) throws RequestException {
- checkRequestSequence(envelope);
-
- try {
- if (request instanceof CreateLocalHistoryRequest) {
- return handleCreateHistory((CreateLocalHistoryRequest) request, envelope, now);
- } else if (request instanceof DestroyLocalHistoryRequest) {
- return handleDestroyHistory((DestroyLocalHistoryRequest) request, envelope, now);
- } else if (request instanceof PurgeLocalHistoryRequest) {
- return handlePurgeHistory((PurgeLocalHistoryRequest)request, envelope, now);
- } else {
- LOG.warn("{}: rejecting unsupported request {}", persistenceId, request);
- throw new UnsupportedRequestException(request);
- }
- } finally {
- expectNextRequest();
- }
+ final long getLastConnectTicks() {
+ return lastConnectTicks;
}
- private LocalHistorySuccess handleCreateHistory(final CreateLocalHistoryRequest request,
- final RequestEnvelope envelope, final long now) throws RequestException {
- final LocalHistoryIdentifier historyId = request.getTarget();
- final AbstractFrontendHistory existing = localHistories.get(historyId);
- if (existing != null) {
- // History already exists: report success
- LOG.debug("{}: history {} already exists", persistenceId, historyId);
- return new LocalHistorySuccess(historyId, request.getSequence());
- }
-
- // We have not found the history. Before we create it we need to check history ID sequencing so that we do not
- // end up resurrecting a purged history.
- if (purgedHistories.contains(historyId.getHistoryId())) {
- LOG.debug("{}: rejecting purged request {}", persistenceId, request);
- throw new DeadHistoryException(purgedHistories.toImmutable());
- }
-
- // Update last history we have seen
- if (lastSeenHistory == null || Long.compareUnsigned(lastSeenHistory, historyId.getHistoryId()) < 0) {
- lastSeenHistory = historyId.getHistoryId();
- }
-
- // We have to send the response only after persistence has completed
- final ShardDataTreeTransactionChain chain = tree.ensureTransactionChain(historyId, () -> {
- LOG.debug("{}: persisted history {}", persistenceId, historyId);
- envelope.sendSuccess(new LocalHistorySuccess(historyId, request.getSequence()), tree.readTime() - now);
- });
-
- localHistories.put(historyId, LocalFrontendHistory.create(persistenceId, tree, chain));
- LOG.debug("{}: created history {}", persistenceId, historyId);
- return null;
+ final long getLastSeenTicks() {
+ return lastSeenTicks;
}
- private LocalHistorySuccess handleDestroyHistory(final DestroyLocalHistoryRequest request,
- final RequestEnvelope envelope, final long now) {
- final LocalHistoryIdentifier id = request.getTarget();
- final LocalFrontendHistory existing = localHistories.get(id);
- if (existing == null) {
- // History does not exist: report success
- LOG.debug("{}: history {} does not exist, nothing to destroy", persistenceId, id);
- return new LocalHistorySuccess(id, request.getSequence());
- }
-
- existing.destroy(request.getSequence(), envelope, now);
- return null;
+ final ShardDataTree tree() {
+ return tree;
}
- private LocalHistorySuccess handlePurgeHistory(final PurgeLocalHistoryRequest request,
- final RequestEnvelope envelope, final long now) {
- final LocalHistoryIdentifier id = request.getTarget();
- final LocalFrontendHistory existing = localHistories.remove(id);
- if (existing == null) {
- LOG.debug("{}: history {} has already been purged", persistenceId, id);
- return new LocalHistorySuccess(id, request.getSequence());
- }
-
- LOG.debug("{}: purging history {}", persistenceId, id);
- purgedHistories.add(id.getHistoryId());
- existing.purge(request.getSequence(), envelope, now);
- return null;
+ final void touch() {
+ this.lastSeenTicks = tree.readTime();
}
- @Nullable TransactionSuccess<?> handleTransactionRequest(final TransactionRequest<?> request,
- final RequestEnvelope envelope, final long now) throws RequestException {
- checkRequestSequence(envelope);
-
- try {
- final LocalHistoryIdentifier lhId = request.getTarget().getHistoryId();
- final AbstractFrontendHistory history;
-
- if (lhId.getHistoryId() != 0) {
- history = localHistories.get(lhId);
- if (history == null) {
- if (purgedHistories.contains(lhId.getHistoryId())) {
- LOG.warn("{}: rejecting request {} to purged history", persistenceId, request);
- throw new DeadHistoryException(purgedHistories.toImmutable());
- }
-
- LOG.warn("{}: rejecting unknown history request {}", persistenceId, request);
- throw new UnknownHistoryException(lastSeenHistory);
- }
- } else {
- history = standaloneHistory;
- }
+ abstract @Nullable LocalHistorySuccess handleLocalHistoryRequest(LocalHistoryRequest<?> request,
+ RequestEnvelope envelope, long now) throws RequestException;
- return history.handleTransactionRequest(request, envelope, now);
- } finally {
- expectNextRequest();
- }
- }
+ abstract @Nullable TransactionSuccess<?> handleTransactionRequest(TransactionRequest<?> request,
+ RequestEnvelope envelope, long now) throws RequestException;
void reconnect() {
- expectedTxSequence = 0;
lastConnectTicks = tree.readTime();
}
}
}
}
-
- // Clear out all transaction chains
- localHistories.values().forEach(AbstractFrontendHistory::retire);
- localHistories.clear();
- standaloneHistory.retire();
- }
-
- long getLastConnectTicks() {
- return lastConnectTicks;
}
- long getLastSeenTicks() {
- return lastSeenTicks;
- }
-
- void touch() {
- this.lastSeenTicks = tree.readTime();
+ @Override
+ public final String toString() {
+ return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
}
- @Override
- public String toString() {
- return MoreObjects.toStringHelper(LeaderFrontendState.class)
- .add("clientId", clientId)
- .add("nanosAgo", tree.readTime() - lastSeenTicks)
- .add("purgedHistories", purgedHistories)
- .toString();
+ ToStringHelper addToStringAttributes(final ToStringHelper helper) {
+ return helper.add("clientId", clientId).add("nanosAgo", tree.readTime() - lastSeenTicks);
}
}
Code Review / controller.git / blobdiff