exec/java-exec/src/main/java/org/apache/drill/exec/rpc/UserClientConnection.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.drill.exec.rpc;

import io.netty.util.concurrent.Future;

import org.apache.drill.exec.physical.impl.materialize.QueryDataPackage;
import org.apache.drill.exec.proto.GeneralRPCProtos.Ack;
import org.apache.drill.exec.proto.UserBitShared.QueryResult;
import org.apache.drill.exec.rpc.user.UserSession;

import java.net.SocketAddress;

/**
 * Interface for getting user session properties and interacting with user
 * connection. Separating this interface from {@link AbstractRemoteConnection}
 * implementation for user connection:
 * <p><ul>
 * <li>Connection is passed to Foreman and Screen operators. Instead passing
 * this interface exposes few details.
 * <li>Makes it easy to have wrappers around user connection which can be
 * helpful to tap the messages and data going to the actual client.
 * </ul>
 */
public interface UserClientConnection {
  /**
   * @return User session object.
   */
  UserSession getSession();

  /**
   * Send query result outcome to client. Outcome is returned through {@code listener}.
   *
   * @param listener
   * @param result
   */
  void sendResult(RpcOutcomeListener<Ack> listener, QueryResult result);

  /**
   * Send query data to client. Outcome is returned through {@code listener}.
   *
   * @param listener
   * @param result
   */
  void sendData(RpcOutcomeListener<Ack> listener, QueryDataPackage data);

  /**
   * Returns the {@link Future} which will be notified when this
   * channel is closed.  This method always returns the same future instance.
   */
  Future<Void> getClosureFuture();

  /**
   * @return Return the client node address.
   */
  SocketAddress getRemoteAddress();
}