Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 1 | /* |
Ray Milkey | 34c9590 | 2015-04-15 09:47:53 -0700 | [diff] [blame] | 2 | * Copyright 2014-2015 Open Networking Laboratory |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
Brian O'Connor | abafb50 | 2014-12-02 22:26:20 -0800 | [diff] [blame] | 16 | package org.onosproject.cluster; |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 17 | |
Madan Jampani | fd45d5e | 2015-04-20 13:33:21 -0700 | [diff] [blame] | 18 | import java.util.List; |
Yuta HIGUCHI | c2bf3d8 | 2014-11-28 18:50:41 -0800 | [diff] [blame] | 19 | import java.util.Map; |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 20 | import java.util.Set; |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 21 | import java.util.concurrent.CompletableFuture; |
Yuta HIGUCHI | c2bf3d8 | 2014-11-28 18:50:41 -0800 | [diff] [blame] | 22 | |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 23 | /** |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 24 | * Service for leader election. |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 25 | * Leadership contests are organized around topics. A instance can join the |
| 26 | * leadership race for a topic or withdraw from a race it has previously joined. |
| 27 | * Listeners can be added to receive notifications asynchronously for various |
| 28 | * leadership contests. |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 29 | */ |
| 30 | public interface LeadershipService { |
| 31 | |
| 32 | /** |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 33 | * Returns the current leader for the topic. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 34 | * |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 35 | * @param path topic |
Madan Jampani | 8d21c79 | 2014-12-01 16:31:07 -0800 | [diff] [blame] | 36 | * @return nodeId of the leader, null if so such topic exists. |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 37 | */ |
Madan Jampani | 8d21c79 | 2014-12-01 16:31:07 -0800 | [diff] [blame] | 38 | NodeId getLeader(String path); |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 39 | |
| 40 | /** |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 41 | * Returns the current leadership info for the topic. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 42 | * |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 43 | * @param path topic |
| 44 | * @return leadership info or null if so such topic exists. |
| 45 | */ |
| 46 | Leadership getLeadership(String path); |
| 47 | |
| 48 | /** |
| 49 | * Returns the set of topics owned by the specified node. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 50 | * |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 51 | * @param nodeId node Id. |
| 52 | * @return set of topics for which this node is the current leader. |
| 53 | */ |
| 54 | Set<String> ownedTopics(NodeId nodeId); |
| 55 | |
| 56 | /** |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 57 | * Joins the leadership contest. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 58 | * |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 59 | * @param path topic for which this controller node wishes to be a leader |
| 60 | * @return {@code Leadership} future |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 61 | */ |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 62 | CompletableFuture<Leadership> runForLeadership(String path); |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 63 | |
| 64 | /** |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 65 | * Withdraws from a leadership contest. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 66 | * |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 67 | * @param path topic for which this controller node no longer wishes to be a leader |
| 68 | * @return future that is successfully completed when withdraw is done |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 69 | */ |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 70 | CompletableFuture<Void> withdraw(String path); |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 71 | |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 72 | /** |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 73 | * If the local nodeId is the leader for specified topic, this method causes it to |
| 74 | * step down temporarily from leadership. |
| 75 | * <p> |
| 76 | * The node will continue to be in contention for leadership and can |
| 77 | * potentially become the leader again if and when it becomes the highest |
| 78 | * priority candidate |
| 79 | * <p> |
Madan Jampani | 9bd1f15 | 2015-04-30 23:33:35 -0700 | [diff] [blame] | 80 | * If the local nodeId is not the leader, this method will make no changes and |
| 81 | * simply return false. |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 82 | * |
| 83 | * @param path topic for which this controller node should give up leadership |
| 84 | * @return true if this node stepped down from leadership, false otherwise |
| 85 | */ |
| 86 | boolean stepdown(String path); |
| 87 | |
| 88 | /** |
| 89 | * Moves the specified nodeId to the top of the candidates list for the topic. |
| 90 | * <p> |
| 91 | * If the node is not a candidate for this topic, this method will be a noop. |
| 92 | * |
| 93 | * @param path leadership topic |
| 94 | * @param nodeId nodeId to make the top candidate |
| 95 | * @return true if nodeId is now the top candidate, false otherwise |
| 96 | */ |
| 97 | boolean makeTopCandidate(String path, NodeId nodeId); |
| 98 | |
| 99 | /** |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 100 | * Returns the current leader board. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 101 | * |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 102 | * @return mapping from topic to leadership info. |
| 103 | */ |
Yuta HIGUCHI | c2bf3d8 | 2014-11-28 18:50:41 -0800 | [diff] [blame] | 104 | Map<String, Leadership> getLeaderBoard(); |
| 105 | |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 106 | /** |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 107 | * Returns the candidates for all known topics. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 108 | * |
Madan Jampani | fd45d5e | 2015-04-20 13:33:21 -0700 | [diff] [blame] | 109 | * @return A mapping from topics to corresponding list of candidates. |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 110 | */ |
Madan Jampani | fd45d5e | 2015-04-20 13:33:21 -0700 | [diff] [blame] | 111 | Map<String, List<NodeId>> getCandidates(); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 112 | |
| 113 | /** |
| 114 | * Returns the candidates for a given topic. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 115 | * |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 116 | * @param path topic |
| 117 | * @return A lists of NodeIds, which may be empty. |
| 118 | */ |
| 119 | List<NodeId> getCandidates(String path); |
| 120 | |
| 121 | /** |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 122 | * Registers a event listener to be notified of leadership events. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 123 | * |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 124 | * @param listener listener that will asynchronously notified of leadership events. |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 125 | */ |
| 126 | void addListener(LeadershipEventListener listener); |
| 127 | |
| 128 | /** |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 129 | * Unregisters a event listener for leadership events. |
Sho SHIMIZU | 25d843c | 2015-04-10 16:52:33 -0700 | [diff] [blame] | 130 | * |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 131 | * @param listener listener to be removed. |
Pavlin Radoslavov | a6b754c | 2014-11-18 13:55:37 -0800 | [diff] [blame] | 132 | */ |
| 133 | void removeListener(LeadershipEventListener listener); |
Brian O'Connor | abafb50 | 2014-12-02 22:26:20 -0800 | [diff] [blame] | 134 | } |