Adding TransportMessage and TransportRequest classes with protobuf in…

…tegration

Signed-off-by: Vacha Shah <[email protected]>

server/src/main/java/org/opensearch/transport/ProtobufTransportMessage.java

@@ -0,0 +1,43 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.transport;
+
+import com.google.protobuf.CodedInputStream;
+import org.opensearch.common.io.stream.ProtobufWriteable;
+import org.opensearch.common.transport.TransportAddress;
+
+/**
+ * Message over the transport interface with Protobuf serialization.
+*
+* @opensearch.internal
+*/
+public abstract class ProtobufTransportMessage implements ProtobufWriteable {
+
+    private TransportAddress remoteAddress;
+
+    public void remoteAddress(TransportAddress remoteAddress) {
+        this.remoteAddress = remoteAddress;
+    }
+
+    public TransportAddress remoteAddress() {
+        return remoteAddress;
+    }
+
+    /**
+     * Constructs a new empty transport message
+    */
+    public ProtobufTransportMessage() {}
+
+    /**
+     * Constructs a new transport message with the data from the {@link CodedInputStream}. This is
+    * currently a no-op
+    */
+    public ProtobufTransportMessage(com.google.protobuf.CodedInputStream in) {}
+}
+

server/src/main/java/org/opensearch/transport/ProtobufTransportRequest.java

@@ -0,0 +1,59 @@
+/*
+* SPDX-License-Identifier: Apache-2.0
+*
+* The OpenSearch Contributors require contributions made to
+* this file be licensed under the Apache-2.0 license or a
+* compatible open source license.
+*/
+
+package org.opensearch.transport;
+
+import com.google.protobuf.CodedInputStream;
+import com.google.protobuf.CodedOutputStream;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.tasks.ProtobufTaskId;
+import org.opensearch.tasks.ProtobufTaskAwareRequest;
+import org.opensearch.tasks.TaskId;
+
+import java.io.IOException;
+
+/**
+ * A transport request with Protobuf serialization.
+*
+* @opensearch.internal
+*/
+public abstract class ProtobufTransportRequest extends ProtobufTransportMessage implements ProtobufTaskAwareRequest {
+
+    /**
+     * Parent of this request. Defaults to {@link TaskId#EMPTY_TASK_ID}, meaning "no parent".
+    */
+    private ProtobufTaskId parentTaskId = ProtobufTaskId.EMPTY_TASK_ID;
+
+    public ProtobufTransportRequest() {}
+
+    public ProtobufTransportRequest(com.google.protobuf.CodedInputStream in) throws IOException {
+        parentTaskId = ProtobufTaskId.readFromStream(in);
+    }
+
+    /**
+     * Set a reference to task that created this request.
+    */
+    @Override
+    public void setParentTask(ProtobufTaskId taskId) {
+        this.parentTaskId = taskId;
+    }
+
+    /**
+     * Get a reference to the task that created this request. Defaults to {@link TaskId#EMPTY_TASK_ID}, meaning "there is no parent".
+    */
+    @Override
+    public ProtobufTaskId getParentTask() {
+        return parentTaskId;
+    }
+
+    @Override
+    public void writeTo(com.google.protobuf.CodedOutputStream out) throws IOException {
+        parentTaskId.writeTo(out);
+    }
+}