package org.opendaylight.controller.cluster.datastore.actors.client;
import com.google.common.annotations.Beta;
+import java.util.Optional;
+import java.util.concurrent.CompletionStage;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
+import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
import org.opendaylight.controller.cluster.access.concepts.ClientIdentifier;
import org.opendaylight.controller.cluster.access.concepts.RequestException;
import org.opendaylight.controller.cluster.access.concepts.RequestFailure;
+import org.opendaylight.controller.cluster.access.concepts.RequestSuccess;
import org.opendaylight.controller.cluster.access.concepts.RetiredGenerationException;
import org.opendaylight.yangtools.concepts.Identifiable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
+import scala.concurrent.duration.FiniteDuration;
/**
* A behavior, which handles messages sent to a {@link AbstractClientActor}.
super(context);
}
+ @Override
+ public final @Nonnull ClientIdentifier getIdentifier() {
+ return context().getIdentifier();
+ }
+
@Override
final ClientActorBehavior onReceiveCommand(final Object command) {
if (command instanceof InternalCommand) {
- return ((InternalCommand) command).execute();
- } else if (command instanceof RequestFailure) {
- final RequestFailure<?, ?> failure = (RequestFailure<?, ?>) command;
- final RequestException cause = failure.getCause();
- if (cause instanceof RetiredGenerationException) {
- LOG.error("{}: current generation {} has been superseded", persistenceId(), getIdentifier(), cause);
- haltClient(cause);
- return null;
- }
+ return ((InternalCommand) command).execute(this);
+ }
+ if (command instanceof RequestSuccess) {
+ return onRequestSuccess((RequestSuccess<?, ?>) command);
+ }
+ if (command instanceof RequestFailure) {
+ return onRequestFailure((RequestFailure<?, ?>) command);
}
- // TODO: any client-common logic (such as validation and common dispatch) needs to go here
return onCommand(command);
}
- @Override
- public final @Nonnull ClientIdentifier getIdentifier() {
- return context().getIdentifier();
+ private ClientActorBehavior onRequestSuccess(final RequestSuccess<?, ?> success) {
+ return context().completeRequest(this, success);
+ }
+
+ private ClientActorBehavior onRequestFailure(final RequestFailure<?, ?> failure) {
+ final RequestException cause = failure.getCause();
+ if (cause instanceof RetiredGenerationException) {
+ LOG.error("{}: current generation {} has been superseded", persistenceId(), getIdentifier(), cause);
+ haltClient(cause);
+ context().poison(cause);
+ return null;
+ }
+
+ if (failure.isHardFailure()) {
+ return context().completeRequest(this, failure);
+ }
+
+ // TODO: add instanceof checks on cause to detect more problems
+
+ LOG.warn("{}: Unhandled retriable failure {}, promoting to hard failure", persistenceId(), failure);
+ return context().completeRequest(this, failure);
+ }
+
+ // This method is executing in the actor context, hence we can safely interact with the queue
+ private ClientActorBehavior doSendRequest(final TransactionRequest<?> request, final RequestCallback callback) {
+ // Get or allocate queue for the request
+ final SequencedQueue queue = context().queueFor(request.getTarget().getHistoryId().getCookie());
+
+ // Note this is a tri-state return and can be null
+ final Optional<FiniteDuration> result = queue.enqueueRequest(request, callback);
+ if (result == null) {
+ // Happy path: we are done here
+ return this;
+ }
+
+ if (result.isPresent()) {
+ // Less happy path: we need to schedule a timer
+ scheduleQueueTimeout(queue, result.get());
+ return this;
+ }
+
+ startResolve(queue, request.getTarget().getHistoryId().getCookie());
+ return this;
+ }
+
+ // This method is executing in the actor context, hence we can safely interact with the queue
+ private void startResolve(final SequencedQueue queue, final long cookie) {
+ // Queue does not have backend information. Initiate resolution, which may actually be piggy-backing on to a
+ // previous request to resolve.
+ final CompletionStage<? extends BackendInfo> f = resolver().getBackendInfo(cookie);
+
+ // This is the tricky part: depending on timing, the queue may have a stale request for resolution, which has
+ // been invalidated or it may already have a reference to this resolution request. Let us give it a chance to
+ // update and it will indicate if this resolution request is an update. If it is, we'll piggy-back on it and
+ // run backend information update in the actor thread. If it is not, we do not need to do anything, as we will
+ // bulk-process all requests.
+ if (queue.expectProof(f)) {
+ f.thenAccept(backend -> context().executeInActor(cb -> cb.finishResolve(queue, f, backend)));
+ }
+ }
+
+ // This method is executing in the actor context, hence we can safely interact with the queue
+ private ClientActorBehavior finishResolve(final SequencedQueue queue,
+ final CompletionStage<? extends BackendInfo> futureBackend, final BackendInfo backend) {
+
+ final Optional<FiniteDuration> maybeTimeout = queue.setBackendInfo(futureBackend, backend);
+ if (maybeTimeout.isPresent()) {
+ scheduleQueueTimeout(queue, maybeTimeout.get());
+ }
+ return this;
+ }
+
+ // This method is executing in the actor context, hence we can safely interact with the queue
+ private void scheduleQueueTimeout(final SequencedQueue queue, final FiniteDuration timeout) {
+ LOG.debug("{}: scheduling timeout in {}", persistenceId(), timeout);
+ context().executeInActor(cb -> cb.queueTimeout(queue), timeout);
+ }
+
+ // This method is executing in the actor context, hence we can safely interact with the queue
+ private ClientActorBehavior queueTimeout(final SequencedQueue queue) {
+ final boolean needBackend;
+
+ try {
+ needBackend = queue.runTimeout();
+ } catch (NoProgressException e) {
+ // Uh-oh, no progress. The queue has already killed itself, now we need to remove it
+ context().removeQueue(queue);
+ return this;
+ }
+
+ if (needBackend) {
+ startResolve(queue, queue.getCookie());
+ }
+
+ return this;
}
/**
* @return
*/
protected abstract @Nonnull BackendInfoResolver<?> resolver();
+
+ /**
+ * Send a request to the backend and invoke a specified callback when it finishes. This method is safe to invoke
+ * from any thread.
+ *
+ * @param request Request to send
+ * @param callback Callback to invoke
+ */
+ public final void sendRequest(final TransactionRequest<?> request, final RequestCallback callback) {
+ context().executeInActor(cb -> cb.doSendRequest(request, callback));
+ }
}
Code Review / controller.git / blobdiff