001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.tracing;
019
020import java.io.IOException;
021import java.util.LinkedList;
022import java.util.List;
023
024import org.apache.hadoop.classification.InterfaceAudience;
025import org.apache.hadoop.classification.InterfaceStability;
026import org.apache.hadoop.fs.CommonConfigurationKeys;
027import org.apache.hadoop.io.retry.AtMostOnce;
028import org.apache.hadoop.io.retry.Idempotent;
029import org.apache.hadoop.ipc.ProtocolInfo;
030import org.apache.hadoop.security.KerberosInfo;
031
032/**
033 * Protocol interface that provides tracing.
034 */
035@KerberosInfo(
036    serverPrincipal=CommonConfigurationKeys.HADOOP_SECURITY_SERVICE_USER_NAME_KEY)
037@InterfaceAudience.Public
038@InterfaceStability.Evolving
039public interface TraceAdminProtocol {
040  public static final long versionID = 1L;
041
042  /**
043   * List the currently active trace span receivers.
044   * 
045   * @throws IOException        On error.
046   */
047  @Idempotent
048  public SpanReceiverInfo[] listSpanReceivers() throws IOException;
049
050  /**
051   * Add a new trace span receiver.
052   * 
053   * @param desc                The span receiver description.
054   * @return                    The ID of the new trace span receiver.
055   *
056   * @throws IOException        On error.
057   */
058  @AtMostOnce
059  public long addSpanReceiver(SpanReceiverInfo desc) throws IOException;
060
061  /**
062   * Remove a trace span receiver.
063   *
064   * @param spanReceiverId      The id of the span receiver to remove.
065   * @throws IOException        On error.
066   */
067  @AtMostOnce
068  public void removeSpanReceiver(long spanReceiverId) throws IOException;
069}