Jin Gan | 79f7537 | 2017-01-05 15:08:11 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016-present Open Networking Laboratory |
| 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 | */ |
| 16 | package org.onosproject.restconf.restconfmanager; |
| 17 | |
| 18 | import com.fasterxml.jackson.databind.node.ObjectNode; |
| 19 | import com.google.common.util.concurrent.ThreadFactoryBuilder; |
| 20 | import org.apache.felix.scr.annotations.Activate; |
| 21 | import org.apache.felix.scr.annotations.Component; |
| 22 | import org.apache.felix.scr.annotations.Deactivate; |
| 23 | import org.apache.felix.scr.annotations.Service; |
| 24 | import org.glassfish.jersey.server.ChunkedOutput; |
| 25 | import org.onosproject.event.ListenerTracker; |
| 26 | import org.onosproject.restconf.api.RestconfException; |
| 27 | import org.onosproject.restconf.api.RestconfService; |
| 28 | import org.slf4j.Logger; |
| 29 | import org.slf4j.LoggerFactory; |
| 30 | |
| 31 | import java.io.IOException; |
| 32 | import java.util.concurrent.BlockingQueue; |
| 33 | import java.util.concurrent.ConcurrentHashMap; |
| 34 | import java.util.concurrent.ConcurrentMap; |
| 35 | import java.util.concurrent.ExecutorService; |
| 36 | import java.util.concurrent.Executors; |
| 37 | import java.util.concurrent.LinkedBlockingQueue; |
| 38 | import java.util.concurrent.ThreadPoolExecutor; |
| 39 | |
| 40 | import static java.util.concurrent.TimeUnit.SECONDS; |
| 41 | import static javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR; |
| 42 | |
| 43 | /* |
| 44 | * Skeletal ONOS RESTCONF Server application. The RESTCONF Manager |
| 45 | * implements the main logic of the RESTCONF Server. |
| 46 | * |
| 47 | * The design of the RESTCONF subsystem contains 2 major bundles: |
| 48 | * |
| 49 | * 1. RESTCONF Protocol Proxy (RPP). This bundle is implemented as a |
| 50 | * JAX-RS application. It acts as the frond-end of the RESTCONF server. |
| 51 | * It intercepts/handles HTTP requests that are sent to the RESTCONF |
| 52 | * Root Path. It then calls the RESTCONF Manager to process the requests. |
| 53 | * |
| 54 | * 2. RESTCONF Manager. This bundle module is the back-end of the server. |
| 55 | * It provides the main logic of the RESTCONF server. It interacts with |
| 56 | * the YMS (YANG Management System) to run operations on the YANG data |
| 57 | * objects (i.e., data resources). |
| 58 | */ |
| 59 | |
| 60 | /** |
| 61 | * Implementation of the RestconfService interface. The class is designed |
| 62 | * as a Apache Flex component. Note that to avoid unnecessary |
| 63 | * activation, the @Component annotation's immediate parameter is set to false. |
| 64 | * So the component is not activated until a RESTCONF request is received by |
| 65 | * the RESTCONF Protocol Proxy (RPP) module, which consumes the service. |
| 66 | */ |
| 67 | @Component(immediate = false) |
| 68 | @Service |
| 69 | public class RestconfManager implements RestconfService { |
| 70 | |
| 71 | private static final String RESTCONF_ROOT = "/onos/restconf"; |
| 72 | private static final int THREAD_TERMINATION_TIMEOUT = 10; |
| 73 | |
| 74 | // Jersey's default chunk parser uses "\r\n" as the chunk separator. |
| 75 | private static final String EOL = "\r\n"; |
| 76 | |
| 77 | private final int maxNumOfWorkerThreads = 5; |
| 78 | |
| 79 | private final Logger log = LoggerFactory.getLogger(getClass()); |
| 80 | |
| 81 | private ListenerTracker listeners; |
| 82 | |
| 83 | private ConcurrentMap<String, BlockingQueue<ObjectNode>> eventQueueList = |
| 84 | new ConcurrentHashMap<>(); |
| 85 | |
| 86 | private ExecutorService workerThreadPool; |
| 87 | |
| 88 | @Activate |
| 89 | protected void activate() { |
| 90 | workerThreadPool = Executors |
| 91 | .newFixedThreadPool(maxNumOfWorkerThreads, |
| 92 | new ThreadFactoryBuilder() |
| 93 | .setNameFormat("restconf-worker") |
| 94 | .build()); |
| 95 | log.info("Started"); |
| 96 | } |
| 97 | |
| 98 | @Deactivate |
| 99 | protected void deactivate() { |
| 100 | shutdownAndAwaitTermination(workerThreadPool); |
| 101 | log.info("Stopped"); |
| 102 | } |
| 103 | |
| 104 | @Override |
| 105 | public ObjectNode runGetOperationOnDataResource(String uri) |
| 106 | throws RestconfException { |
| 107 | |
| 108 | return null; |
| 109 | } |
| 110 | |
| 111 | @Override |
| 112 | public void runPostOperationOnDataResource(String uri, ObjectNode rootNode) |
| 113 | throws RestconfException { |
| 114 | } |
| 115 | |
| 116 | @Override |
| 117 | public void runPutOperationOnDataResource(String uri, ObjectNode rootNode) |
| 118 | throws RestconfException { |
| 119 | } |
| 120 | |
| 121 | @Override |
| 122 | public void runDeleteOperationOnDataResource(String uri) |
| 123 | throws RestconfException { |
| 124 | } |
| 125 | |
| 126 | @Override |
| 127 | public void runPatchOperationOnDataResource(String uri, ObjectNode rootNode) |
| 128 | throws RestconfException { |
| 129 | } |
| 130 | |
| 131 | @Override |
| 132 | public String getRestconfRootPath() { |
| 133 | return RESTCONF_ROOT; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * Creates a worker thread to listen to events and write to chunkedOutput. |
| 138 | * The worker thread blocks if no events arrive. |
| 139 | * |
| 140 | * @param streamId the RESTCONF stream id to which the client subscribes |
| 141 | * @param output the string data stream |
| 142 | * @throws RestconfException if the worker thread fails to create |
| 143 | */ |
| 144 | @Override |
| 145 | public void subscribeEventStream(String streamId, |
| 146 | ChunkedOutput<String> output) |
| 147 | throws RestconfException { |
| 148 | if (workerThreadPool instanceof ThreadPoolExecutor) { |
| 149 | if (((ThreadPoolExecutor) workerThreadPool).getActiveCount() >= |
| 150 | maxNumOfWorkerThreads) { |
| 151 | throw new RestconfException("no more work threads left to " + |
| 152 | "handle event subscription", |
| 153 | INTERNAL_SERVER_ERROR); |
| 154 | } |
| 155 | } else { |
| 156 | throw new RestconfException("Server ERROR: workerThreadPool NOT " + |
| 157 | "instanceof ThreadPoolExecutor", |
| 158 | INTERNAL_SERVER_ERROR); |
| 159 | |
| 160 | } |
| 161 | |
| 162 | BlockingQueue<ObjectNode> eventQueue = new LinkedBlockingQueue<>(); |
| 163 | workerThreadPool.submit(new EventConsumer(output, eventQueue)); |
| 164 | } |
| 165 | |
| 166 | /** |
| 167 | * Shutdown a pool cleanly if possible. |
| 168 | * |
| 169 | * @param pool an executorService |
| 170 | */ |
| 171 | private void shutdownAndAwaitTermination(ExecutorService pool) { |
| 172 | pool.shutdown(); // Disable new tasks from being submitted |
| 173 | try { |
| 174 | // Wait a while for existing tasks to terminate |
| 175 | if (!pool.awaitTermination(THREAD_TERMINATION_TIMEOUT, SECONDS)) { |
| 176 | pool.shutdownNow(); // Cancel currently executing tasks |
| 177 | // Wait a while for tasks to respond to being cancelled |
| 178 | if (!pool.awaitTermination(THREAD_TERMINATION_TIMEOUT, |
| 179 | SECONDS)) { |
| 180 | log.error("Pool did not terminate"); |
| 181 | } |
| 182 | } |
| 183 | } catch (Exception ie) { |
| 184 | // (Re-)Cancel if current thread also interrupted |
| 185 | pool.shutdownNow(); |
| 186 | // Preserve interrupt status |
| 187 | Thread.currentThread().interrupt(); |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Implementation of a worker thread which reads data from a |
| 193 | * blocking queue and writes the data to a given chunk output stream. |
| 194 | * The thread is blocked when no data arrive to the queue and is |
| 195 | * terminated when the chunk output stream is closed (i.e., the |
| 196 | * HTTP-keep-alive session is closed). |
| 197 | */ |
| 198 | private class EventConsumer implements Runnable { |
| 199 | |
| 200 | private String queueId; |
| 201 | private final ChunkedOutput<String> output; |
| 202 | private final BlockingQueue<ObjectNode> bqueue; |
| 203 | |
| 204 | public EventConsumer(ChunkedOutput<String> output, |
| 205 | BlockingQueue<ObjectNode> q) { |
| 206 | this.output = output; |
| 207 | this.bqueue = q; |
| 208 | } |
| 209 | |
| 210 | @Override |
| 211 | public void run() { |
| 212 | try { |
| 213 | queueId = String.valueOf(Thread.currentThread().getId()); |
| 214 | eventQueueList.put(queueId, bqueue); |
| 215 | log.debug("EventConsumer thread created: {}", queueId); |
| 216 | |
| 217 | ObjectNode chunk; |
| 218 | while ((chunk = bqueue.take()) != null) { |
| 219 | output.write(chunk.toString().concat(EOL)); |
| 220 | } |
| 221 | } catch (IOException e) { |
| 222 | log.debug("chunkedOuput is closed: {}", this.bqueue.toString()); |
| 223 | /* |
| 224 | * Remove queue from the queue list, so that the event producer |
| 225 | * (i.e., listener) would stop working. |
| 226 | */ |
| 227 | eventQueueList.remove(this.queueId); |
| 228 | } catch (InterruptedException e) { |
| 229 | log.error("ERROR: EventConsumer: bqueue.take() " + |
| 230 | "has been interrupted."); |
| 231 | log.debug("EventConsumer Exception:", e); |
| 232 | } finally { |
| 233 | try { |
| 234 | output.close(); |
| 235 | log.debug("EventConsumer thread terminated: {}", queueId); |
| 236 | } catch (IOException e) { |
| 237 | log.error("ERROR: EventConsumer: ", e); |
| 238 | } |
| 239 | } |
| 240 | } |
| 241 | } |
| 242 | } |