State machine implementations for various distributed primitives based on latest Copycat APIs
Change-Id: I622cc196aa1cdf072a5a0b100a5ffaaf71b07900
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixLeaderElector.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixLeaderElector.java
new file mode 100644
index 0000000..b18d3da
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixLeaderElector.java
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.store.primitives.resources.impl;
+
+import io.atomix.catalyst.util.Listener;
+import io.atomix.copycat.client.CopycatClient;
+import io.atomix.resource.Consistency;
+import io.atomix.resource.Resource;
+import io.atomix.resource.ResourceTypeInfo;
+
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.function.Consumer;
+
+import org.onosproject.cluster.Leadership;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.event.Change;
+import org.onosproject.store.service.AsyncLeaderElector;
+
+import com.google.common.collect.Sets;
+
+/**
+ * Distributed resource providing the {@link AsyncLeaderElector} primitive.
+ */
+@ResourceTypeInfo(id = -152, stateMachine = AtomixLeaderElectorState.class)
+public class AtomixLeaderElector
+ extends Resource<AtomixLeaderElector, Resource.Options> implements AsyncLeaderElector {
+ private final Set<Consumer<Change<Leadership>>> leadershipChangeListeners =
+ Sets.newConcurrentHashSet();
+
+ private Listener<Change<Leadership>> listener;
+
+ public AtomixLeaderElector(CopycatClient client, Resource.Options options) {
+ super(client, options);
+ }
+
+ @Override
+ public String name() {
+ return null;
+ }
+
+ @Override
+ public CompletableFuture<AtomixLeaderElector> open() {
+ return super.open().thenApply(result -> {
+ client.session().onEvent("change", this::handleEvent);
+ return result;
+ });
+ }
+
+ private void handleEvent(Change<Leadership> change) {
+ leadershipChangeListeners.forEach(l -> l.accept(change));
+ }
+
+ @Override
+ public AtomixLeaderElector with(Consistency consistency) {
+ super.with(consistency);
+ return this;
+ }
+
+ @Override
+ public CompletableFuture<Leadership> run(String topic, NodeId nodeId) {
+ return submit(new AtomixLeaderElectorCommands.Run(topic, nodeId));
+ }
+
+ @Override
+ public CompletableFuture<Void> withdraw(String topic) {
+ return submit(new AtomixLeaderElectorCommands.Withdraw(topic));
+ }
+
+ @Override
+ public CompletableFuture<Boolean> anoint(String topic, NodeId nodeId) {
+ return submit(new AtomixLeaderElectorCommands.Anoint(topic, nodeId));
+ }
+
+ @Override
+ public CompletableFuture<Leadership> getLeadership(String topic) {
+ return submit(new AtomixLeaderElectorCommands.GetLeadership(topic));
+ }
+
+ @Override
+ public CompletableFuture<Map<String, Leadership>> getLeaderships() {
+ return submit(new AtomixLeaderElectorCommands.GetAllLeaderships());
+ }
+
+ public CompletableFuture<Set<String>> getElectedTopics(NodeId nodeId) {
+ return submit(new AtomixLeaderElectorCommands.GetElectedTopics(nodeId));
+ }
+
+ /**
+ * Leadership change listener context.
+ */
+ private final class LeadershipChangeListener implements Listener<Change<Leadership>> {
+ private final Consumer<Change<Leadership>> listener;
+
+ private LeadershipChangeListener(Consumer<Change<Leadership>> listener) {
+ this.listener = listener;
+ }
+
+ @Override
+ public void accept(Change<Leadership> change) {
+ listener.accept(change);
+ }
+
+ @Override
+ public void close() {
+ synchronized (AtomixLeaderElector.this) {
+ submit(new AtomixLeaderElectorCommands.Unlisten());
+ }
+ }
+ }
+
+ @Override
+ public CompletableFuture<Void> addChangeListener(Consumer<Change<Leadership>> consumer) {
+ leadershipChangeListeners.add(consumer);
+ return setupListener();
+ }
+
+ @Override
+ public CompletableFuture<Void> removeChangeListener(Consumer<Change<Leadership>> consumer) {
+ leadershipChangeListeners.remove(consumer);
+ return teardownListener();
+ }
+
+ private CompletableFuture<Void> setupListener() {
+ if (listener == null && !leadershipChangeListeners.isEmpty()) {
+ Consumer<Change<Leadership>> changeConsumer = change -> {
+ leadershipChangeListeners.forEach(consumer -> consumer.accept(change));
+ };
+ return submit(new AtomixLeaderElectorCommands.Listen())
+ .thenAccept(v -> listener = new LeadershipChangeListener(changeConsumer));
+ }
+ return CompletableFuture.completedFuture(null);
+ }
+
+ private CompletableFuture<Void> teardownListener() {
+ if (listener != null && leadershipChangeListeners.isEmpty()) {
+ listener.close();
+ listener = null;
+ return submit(new AtomixLeaderElectorCommands.Unlisten());
+ }
+ return CompletableFuture.completedFuture(null);
+ }
+}