+ private void applyReplicatedCandidate(final CommitTransactionPayload payload)
+ throws DataValidationFailedException, IOException {
+ final Entry<TransactionIdentifier, DataTreeCandidateWithVersion> entry = payload.acquireCandidate();
+ final TransactionIdentifier identifier = entry.getKey();
+ LOG.debug("{}: Applying foreign transaction {}", logContext, identifier);
+
+ final DataTreeModification mod = dataTree.takeSnapshot().newModification();
+ // TODO: check version here, which will enable us to perform forward-compatibility transformations
+ DataTreeCandidates.applyToModification(mod, entry.getValue().getCandidate());
+ mod.ready();
+
+ LOG.trace("{}: Applying foreign modification {}", logContext, mod);
+ dataTree.validate(mod);
+ final DataTreeCandidate candidate = dataTree.prepare(mod);
+ dataTree.commit(candidate);
+
+ allMetadataCommittedTransaction(identifier);
+ notifyListeners(candidate);
+ }
+
+ /**
+ * Apply a payload coming from the leader, which could actually be us. This method assumes the leader and follower
+ * SchemaContexts match and does not perform any pruning.
+ *
+ * @param identifier Payload identifier as returned from RaftActor
+ * @param payload Payload
+ * @throws IOException when the snapshot fails to deserialize
+ * @throws DataValidationFailedException when the snapshot fails to apply
+ */
+ void applyReplicatedPayload(final Identifier identifier, final Payload payload) throws IOException,
+ DataValidationFailedException {
+ /*
+ * This is a bit more involved than it needs to be due to to the fact we do not want to be touching the payload
+ * if we are the leader and it has originated with us.
+ *
+ * The identifier will only ever be non-null when we were the leader which achieved consensus. Unfortunately,
+ * though, this may not be the case anymore, as we are being called some time afterwards and we may not be
+ * acting in that capacity anymore.
+ *
+ * In any case, we know that this is an entry coming from replication, hence we can be sure we will not observe
+ * pre-Boron state -- which limits the number of options here.
+ */
+ if (payload instanceof CommitTransactionPayload) {
+ if (identifier == null) {
+ applyReplicatedCandidate((CommitTransactionPayload) payload);
+ } else {
+ verify(identifier instanceof TransactionIdentifier);
+ // if we did not track this transaction before, it means that it came from another leader and we are in
+ // the process of commiting it while in PreLeader state. That means that it hasnt yet been committed to
+ // the local DataTree and would be lost if it was only applied via payloadReplicationComplete().
+ if (!payloadReplicationComplete((TransactionIdentifier) identifier)) {
+ applyReplicatedCandidate((CommitTransactionPayload) payload);
+ }
+ }
+ } else if (payload instanceof AbortTransactionPayload) {
+ if (identifier != null) {
+ payloadReplicationComplete((AbortTransactionPayload) payload);
+ }
+ allMetadataAbortedTransaction(((AbortTransactionPayload) payload).getIdentifier());
+ } else if (payload instanceof PurgeTransactionPayload) {
+ if (identifier != null) {
+ payloadReplicationComplete((PurgeTransactionPayload) payload);
+ }
+ allMetadataPurgedTransaction(((PurgeTransactionPayload) payload).getIdentifier());
+ } else if (payload instanceof CloseLocalHistoryPayload) {
+ if (identifier != null) {
+ payloadReplicationComplete((CloseLocalHistoryPayload) payload);
+ }
+ allMetadataClosedLocalHistory(((CloseLocalHistoryPayload) payload).getIdentifier());
+ } else if (payload instanceof CreateLocalHistoryPayload) {
+ if (identifier != null) {
+ payloadReplicationComplete((CreateLocalHistoryPayload)payload);
+ }
+ allMetadataCreatedLocalHistory(((CreateLocalHistoryPayload) payload).getIdentifier());
+ } else if (payload instanceof PurgeLocalHistoryPayload) {
+ if (identifier != null) {
+ payloadReplicationComplete((PurgeLocalHistoryPayload)payload);
+ }
+ allMetadataPurgedLocalHistory(((PurgeLocalHistoryPayload) payload).getIdentifier());
+ } else {
+ LOG.warn("{}: ignoring unhandled identifier {} payload {}", logContext, identifier, payload);
+ }
+ }
+
+ private void replicatePayload(final Identifier id, final Payload payload, final @Nullable Runnable callback) {
+ if (callback != null) {
+ replicationCallbacks.put(payload, callback);
+ }
+ shard.persistPayload(id, payload, true);
+ }
+
+ private void payloadReplicationComplete(final AbstractIdentifiablePayload<?> payload) {
+ final Runnable callback = replicationCallbacks.remove(payload);
+ if (callback != null) {
+ LOG.debug("{}: replication of {} completed, invoking {}", logContext, payload.getIdentifier(), callback);
+ callback.run();
+ } else {
+ LOG.debug("{}: replication of {} has no callback", logContext, payload.getIdentifier());
+ }
+ }
+
+ private boolean payloadReplicationComplete(final TransactionIdentifier txId) {
+ final CommitEntry current = pendingFinishCommits.peek();
+ if (current == null) {
+ LOG.warn("{}: No outstanding transactions, ignoring consensus on transaction {}", logContext, txId);
+ allMetadataCommittedTransaction(txId);
+ return false;
+ }
+
+ if (!current.cohort.getIdentifier().equals(txId)) {
+ LOG.debug("{}: Head of pendingFinishCommits queue is {}, ignoring consensus on transaction {}", logContext,
+ current.cohort.getIdentifier(), txId);
+ allMetadataCommittedTransaction(txId);
+ return false;
+ }
+
+ finishCommit(current.cohort);
+ return true;
+ }
+
+ private void allMetadataAbortedTransaction(final TransactionIdentifier txId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onTransactionAborted(txId);
+ }
+ }
+
+ private void allMetadataCommittedTransaction(final TransactionIdentifier txId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onTransactionCommitted(txId);
+ }
+ }
+
+ private void allMetadataPurgedTransaction(final TransactionIdentifier txId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onTransactionPurged(txId);
+ }
+ }
+
+ private void allMetadataCreatedLocalHistory(final LocalHistoryIdentifier historyId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onHistoryCreated(historyId);
+ }
+ }
+
+ private void allMetadataClosedLocalHistory(final LocalHistoryIdentifier historyId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onHistoryClosed(historyId);
+ }
+ }
+
+ private void allMetadataPurgedLocalHistory(final LocalHistoryIdentifier historyId) {
+ for (ShardDataTreeMetadata<?> m : metadata) {
+ m.onHistoryPurged(historyId);
+ }
+ }
+
+ /**
+ * Create a transaction chain for specified history. Unlike {@link #ensureTransactionChain(LocalHistoryIdentifier)},
+ * this method is used for re-establishing state when we are taking over
+ *
+ * @param historyId Local history identifier
+ * @param closed True if the chain should be created in closed state (i.e. pending purge)
+ * @return Transaction chain handle
+ */
+ ShardDataTreeTransactionChain recreateTransactionChain(final LocalHistoryIdentifier historyId,
+ final boolean closed) {
+ final ShardDataTreeTransactionChain ret = new ShardDataTreeTransactionChain(historyId, this);
+ final ShardDataTreeTransactionChain existing = transactionChains.putIfAbsent(historyId, ret);
+ checkState(existing == null, "Attempted to recreate chain %s, but %s already exists", historyId, existing);
+ return ret;
+ }
+
+ ShardDataTreeTransactionChain ensureTransactionChain(final LocalHistoryIdentifier historyId,
+ final @Nullable Runnable callback) {
+ ShardDataTreeTransactionChain chain = transactionChains.get(historyId);