Implement service for registering, managing, and operating on remote Java proxies over the cluster communication service
Change-Id: I4576e3554cfad08747eed847b73fe695e219f3b8
diff --git a/core/api/src/main/java/org/onosproject/cluster/ProxyFactory.java b/core/api/src/main/java/org/onosproject/cluster/ProxyFactory.java
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+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.cluster;
+
+/**
+ * Constructs proxy instances for nodes in the cluster.
+ * <p>
+ * The proxy factory constructs proxy instances for the master node of a given {@link NodeId}.
+ * When a proxy method is invoked, the method will be called on the provided node.
+ */
+public interface ProxyFactory<T> {
+
+ /**
+ * Returns the proxy for the given peer.
+ * <p>
+ * The proxy instance is a multiton that is cached internally in the factory, so calling this method
+ *
+ * @param nodeId the peer node identifier
+ * @return the proxy for the given peer
+ */
+ T getProxyFor(NodeId nodeId);
+
+}
diff --git a/core/api/src/main/java/org/onosproject/cluster/ProxyService.java b/core/api/src/main/java/org/onosproject/cluster/ProxyService.java
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+++ b/core/api/src/main/java/org/onosproject/cluster/ProxyService.java
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+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.cluster;
+
+import org.onosproject.store.service.Serializer;
+
+/**
+ * Manages remote proxy services and instances.
+ * <p>
+ * This service can be used to make arbitrary method calls on remote objects in ONOS. The objects on which the methods
+ * are called are referred to as <em>services</em> and are made available to the proxy service by
+ * {@link #registerProxyService(Class, Object, Serializer) registering} a service instance. Services must implement
+ * an <em>interface</em> which can be used to construct a Java proxy. Proxy interfaces may define either synchronous
+ * or asynchronous methods. Synchronous proxy methods will be blocked, and asynchronous proxy methods (which must
+ * return {@link java.util.concurrent.CompletableFuture}) will be proxied using asynchronous intra-cluster
+ * communication. To make a remote call on a proxy service, get an instance of the {@link ProxyFactory} for the service
+ * type using {@link #getProxyFactory(Class, Serializer)}. The proxy factory is responsible for constructing proxy
+ * instances for each node in the cluster. Once a proxy instance is constructed, calls on the proxy instance will be
+ * transparently serialized and sent to the associated peer and be executed on the proxy service registered by that
+ * peer.
+ */
+public interface ProxyService {
+
+ /**
+ * Returns a new proxy factory for the given type.
+ * <p>
+ * The proxy {@code type} passed to this method must be an interface. The proxy factory can be used to construct
+ * proxy instances for different nodes in the cluster.
+ *
+ * @param type the proxy type
+ * @param serializer the proxy serializer
+ * @param <T> the proxy type
+ * @return the proxy factory
+ * @throws IllegalArgumentException if the {@code type} is not an interface
+ */
+ <T> ProxyFactory<T> getProxyFactory(Class<T> type, Serializer serializer);
+
+ /**
+ * Registers a proxy service.
+ * <p>
+ * The proxy {@code type} passed to this method must be an interface. The {@code proxy} should be an implementation
+ * of that interface on which methods will be called when proxy calls from other nodes are received.
+ *
+ * @param type the proxy type
+ * @param proxy the proxy service
+ * @param serializer the proxy serializer
+ * @param <T> the proxy type
+ * @throws IllegalArgumentException if the {@code type} is not an interface
+ */
+ <T> void registerProxyService(Class<? super T> type, T proxy, Serializer serializer);
+
+ /**
+ * Unregisters the proxy service of the given type.
+ * <p>
+ * Once the proxy service has been unregistered, calls to the proxy instance on this node will fail.
+ *
+ * @param type the proxy service type to unregister
+ */
+ void unregisterProxyService(Class<?> type);
+
+}