1 package org.opendaylight.controller.sal.streams.listeners;
3 import io.netty.channel.Channel;
4 import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
5 import io.netty.util.internal.ConcurrentSet;
7 import java.io.ByteArrayOutputStream;
8 import java.io.OutputStreamWriter;
9 import java.io.UnsupportedEncodingException;
10 import java.text.SimpleDateFormat;
11 import java.util.Collection;
12 import java.util.Date;
13 import java.util.HashMap;
15 import java.util.Map.Entry;
16 import java.util.Random;
18 import java.util.concurrent.Executors;
20 import javax.activation.UnsupportedDataTypeException;
21 import javax.xml.parsers.DocumentBuilder;
22 import javax.xml.parsers.DocumentBuilderFactory;
23 import javax.xml.parsers.ParserConfigurationException;
24 import javax.xml.transform.OutputKeys;
25 import javax.xml.transform.Transformer;
26 import javax.xml.transform.TransformerException;
27 import javax.xml.transform.TransformerFactory;
28 import javax.xml.transform.dom.DOMSource;
29 import javax.xml.transform.stream.StreamResult;
31 import org.opendaylight.controller.md.sal.common.api.data.DataChangeEvent;
32 import org.opendaylight.controller.sal.core.api.data.DataChangeListener;
33 import org.opendaylight.controller.sal.rest.impl.XmlMapper;
34 import org.opendaylight.controller.sal.restconf.impl.ControllerContext;
35 import org.opendaylight.yangtools.concepts.ListenerRegistration;
36 import org.opendaylight.yangtools.yang.common.QName;
37 import org.opendaylight.yangtools.yang.data.api.CompositeNode;
38 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
39 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.NodeIdentifierWithPredicates;
40 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.NodeWithValue;
41 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
42 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
43 import org.slf4j.Logger;
44 import org.slf4j.LoggerFactory;
45 import org.w3c.dom.Document;
46 import org.w3c.dom.Element;
47 import org.w3c.dom.Node;
49 import com.google.common.base.Preconditions;
50 import com.google.common.eventbus.AsyncEventBus;
51 import com.google.common.eventbus.EventBus;
52 import com.google.common.eventbus.Subscribe;
55 * {@link ListenerAdapter} is responsible to track events, which occurred by
56 * changing data in data source.
58 public class ListenerAdapter implements DataChangeListener {
60 private static final Logger logger = LoggerFactory
61 .getLogger(ListenerAdapter.class);
62 private final XmlMapper xmlMapper = new XmlMapper();
63 private final SimpleDateFormat rfc3339 = new SimpleDateFormat(
64 "yyyy-MM-dd'T'hh:mm:ssZ");
66 private final InstanceIdentifier path;
67 private ListenerRegistration<DataChangeListener> registration;
68 private final String streamName;
69 private Set<Channel> subscribers = new ConcurrentSet<>();
70 private final EventBus eventBus;
71 private final EventBusChangeRecorder eventBusChangeRecorder;
74 * Creates new {@link ListenerAdapter} listener specified by path and stream
78 * Path to data in data store.
80 * The name of the stream.
82 ListenerAdapter(InstanceIdentifier path, String streamName) {
83 Preconditions.checkNotNull(path);
85 .checkArgument(streamName != null && !streamName.isEmpty());
87 this.streamName = streamName;
88 eventBus = new AsyncEventBus(Executors.newSingleThreadExecutor());
89 eventBusChangeRecorder = new EventBusChangeRecorder();
90 eventBus.register(eventBusChangeRecorder);
94 public void onDataChanged(
95 DataChangeEvent<InstanceIdentifier, CompositeNode> change) {
96 if (!change.getCreatedConfigurationData().isEmpty()
97 || !change.getCreatedOperationalData().isEmpty()
98 || !change.getUpdatedConfigurationData().isEmpty()
99 || !change.getUpdatedOperationalData().isEmpty()
100 || !change.getRemovedConfigurationData().isEmpty()
101 || !change.getRemovedOperationalData().isEmpty()) {
102 String xml = prepareXmlFrom(change);
103 Event event = new Event(EventType.NOTIFY);
105 eventBus.post(event);
110 * Tracks events of data change by customer.
112 private final class EventBusChangeRecorder {
114 public void recordCustomerChange(Event event) {
115 if (event.getType() == EventType.REGISTER) {
116 Channel subscriber = event.getSubscriber();
117 if (!subscribers.contains(subscriber)) {
118 subscribers.add(subscriber);
120 } else if (event.getType() == EventType.DEREGISTER) {
121 subscribers.remove(event.getSubscriber());
123 .removeListenerIfNoSubscriberExists(ListenerAdapter.this);
124 } else if (event.getType() == EventType.NOTIFY) {
125 for (Channel subscriber : subscribers) {
126 if (subscriber.isActive()) {
127 logger.debug("Data are sent to subscriber {}:",
128 subscriber.remoteAddress());
129 subscriber.writeAndFlush(new TextWebSocketFrame(event
133 "Subscriber {} is removed - channel is not active yet.",
134 subscriber.remoteAddress());
135 subscribers.remove(subscriber);
143 * Represents event of specific {@link EventType} type, holds data and
144 * {@link Channel} subscriber.
146 private final class Event {
147 private final EventType type;
148 private Channel subscriber;
152 * Creates new event specified by {@link EventType} type.
157 public Event(EventType type) {
162 * Gets the {@link Channel} subscriber.
166 public Channel getSubscriber() {
171 * Sets subscriber for event.
176 public void setSubscriber(Channel subscriber) {
177 this.subscriber = subscriber;
183 * @return String representation of event data.
185 public String getData() {
195 public void setData(String data) {
202 * @return The type of the event.
204 public EventType getType() {
212 private enum EventType {
213 REGISTER, DEREGISTER, NOTIFY;
217 * Prepare data in printable form and transform it to String.
221 * @return Data in printable form.
223 private String prepareXmlFrom(
224 DataChangeEvent<InstanceIdentifier, CompositeNode> change) {
225 Document doc = createDocument();
226 Element notificationElement = doc.createElementNS(
227 "urn:ietf:params:xml:ns:netconf:notification:1.0",
229 doc.appendChild(notificationElement);
231 Element eventTimeElement = doc.createElement("eventTime");
232 eventTimeElement.setTextContent(toRFC3339(new Date()));
233 notificationElement.appendChild(eventTimeElement);
235 Element dataChangedNotificationEventElement = doc.createElementNS(
236 "urn:opendaylight:params:xml:ns:yang:controller:md:sal:remote",
237 "data-changed-notification");
238 addValuesToDataChangedNotificationEventElement(doc,
239 dataChangedNotificationEventElement, change);
240 notificationElement.appendChild(dataChangedNotificationEventElement);
243 ByteArrayOutputStream out = new ByteArrayOutputStream();
244 TransformerFactory tf = TransformerFactory.newInstance();
245 Transformer transformer = tf.newTransformer();
247 .setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
248 transformer.setOutputProperty(OutputKeys.METHOD, "xml");
249 transformer.setOutputProperty(OutputKeys.INDENT, "yes");
250 transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
251 transformer.setOutputProperty(
252 "{http://xml.apache.org/xslt}indent-amount", "4");
253 transformer.transform(new DOMSource(doc), new StreamResult(
254 new OutputStreamWriter(out, "UTF-8")));
255 byte[] charData = out.toByteArray();
256 return new String(charData, "UTF-8");
257 } catch (TransformerException | UnsupportedEncodingException e) {
258 String msg = "Error during transformation of Document into String";
259 logger.error(msg, e);
265 * Formats data specified by RFC3339.
269 * @return Data specified by RFC3339.
271 private String toRFC3339(Date d) {
272 return rfc3339.format(d).replaceAll("(\\d\\d)(\\d\\d)$", "$1:$2");
276 * Creates {@link Document} document.
278 * @return {@link Document} document.
280 private Document createDocument() {
281 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
284 DocumentBuilder bob = dbf.newDocumentBuilder();
285 doc = bob.newDocument();
286 } catch (ParserConfigurationException e) {
293 * Adds values to data changed notification event element.
297 * @param dataChangedNotificationEventElement
300 * {@link DataChangeEvent}
302 private void addValuesToDataChangedNotificationEventElement(Document doc,
303 Element dataChangedNotificationEventElement,
304 DataChangeEvent<InstanceIdentifier, CompositeNode> change) {
305 addValuesFromDataToElement(doc, change.getCreatedConfigurationData(),
306 dataChangedNotificationEventElement, Store.CONFIG,
308 addValuesFromDataToElement(doc, change.getCreatedOperationalData(),
309 dataChangedNotificationEventElement, Store.OPERATION,
311 if (change.getCreatedConfigurationData().isEmpty()) {
312 addValuesFromDataToElement(doc,
313 change.getUpdatedConfigurationData(),
314 dataChangedNotificationEventElement, Store.CONFIG,
317 if (change.getCreatedOperationalData().isEmpty()) {
318 addValuesFromDataToElement(doc, change.getUpdatedOperationalData(),
319 dataChangedNotificationEventElement, Store.OPERATION,
322 addValuesFromDataToElement(doc, change.getRemovedConfigurationData(),
323 dataChangedNotificationEventElement, Store.CONFIG,
325 addValuesFromDataToElement(doc, change.getRemovedOperationalData(),
326 dataChangedNotificationEventElement, Store.OPERATION,
331 * Adds values from data to element.
336 * Set of {@link InstanceIdentifier}.
344 private void addValuesFromDataToElement(Document doc,
345 Set<InstanceIdentifier> data, Element element, Store store,
346 Operation operation) {
347 if (data == null || data.isEmpty()) {
350 for (InstanceIdentifier path : data) {
351 Node node = createDataChangeEventElement(doc, path, null, store,
353 element.appendChild(node);
358 * Adds values from data to element.
363 * Map of {@link InstanceIdentifier} and {@link CompositeNode}.
371 private void addValuesFromDataToElement(Document doc,
372 Map<InstanceIdentifier, CompositeNode> data, Element element,
373 Store store, Operation operation) {
374 if (data == null || data.isEmpty()) {
377 for (Entry<InstanceIdentifier, CompositeNode> entry : data.entrySet()) {
378 Node node = createDataChangeEventElement(doc, entry.getKey(),
379 entry.getValue(), store, operation);
380 element.appendChild(node);
385 * Creates changed event element from data.
390 * Path to data in data store.
392 * {@link CompositeNode}
397 * @return {@link Node} node represented by changed event element.
399 private Node createDataChangeEventElement(Document doc,
400 InstanceIdentifier path, CompositeNode data, Store store,
401 Operation operation) {
402 Element dataChangeEventElement = doc.createElement("data-change-event");
404 Element pathElement = doc.createElement("path");
405 addPathAsValueToElement(path, pathElement);
406 dataChangeEventElement.appendChild(pathElement);
408 Element storeElement = doc.createElement("store");
409 storeElement.setTextContent(store.value);
410 dataChangeEventElement.appendChild(storeElement);
412 Element operationElement = doc.createElement("operation");
413 operationElement.setTextContent(operation.value);
414 dataChangeEventElement.appendChild(operationElement);
417 Element dataElement = doc.createElement("data");
418 Node dataAnyXml = translateToXml(path, data);
419 Node adoptedNode = doc.adoptNode(dataAnyXml);
420 dataElement.appendChild(adoptedNode);
421 dataChangeEventElement.appendChild(dataElement);
424 return dataChangeEventElement;
428 * Translates {@link CompositeNode} data to XML format.
431 * Path to data in data store.
433 * {@link CompositeNode}
434 * @return Data in XML format.
436 private Node translateToXml(InstanceIdentifier path, CompositeNode data) {
437 DataNodeContainer schemaNode = ControllerContext.getInstance()
438 .getDataNodeContainerFor(path);
439 if (schemaNode == null) {
441 "Path '{}' contains node with unsupported type (supported type is Container or List) or some node was not found.",
446 Document xml = xmlMapper.write(data, schemaNode);
447 return xml.getFirstChild();
448 } catch (UnsupportedDataTypeException e) {
450 "Error occured during translation of notification to XML.",
457 * Adds path as value to element.
460 * Path to data in data store.
464 private void addPathAsValueToElement(InstanceIdentifier path,
466 // Map< key = namespace, value = prefix>
467 Map<String, String> prefixes = new HashMap<>();
468 InstanceIdentifier instanceIdentifier = path;
469 StringBuilder textContent = new StringBuilder();
470 for (PathArgument pathArgument : instanceIdentifier.getPath()) {
471 textContent.append("/");
472 writeIdentifierWithNamespacePrefix(element, textContent,
473 pathArgument.getNodeType(), prefixes);
474 if (pathArgument instanceof NodeIdentifierWithPredicates) {
475 Map<QName, Object> predicates = ((NodeIdentifierWithPredicates) pathArgument)
477 for (QName keyValue : predicates.keySet()) {
478 String predicateValue = String.valueOf(predicates
480 textContent.append("[");
481 writeIdentifierWithNamespacePrefix(element, textContent,
483 textContent.append("='");
484 textContent.append(predicateValue);
485 textContent.append("'");
486 textContent.append("]");
488 } else if (pathArgument instanceof NodeWithValue) {
489 textContent.append("[.='");
490 textContent.append(((NodeWithValue) pathArgument).getValue());
491 textContent.append("'");
492 textContent.append("]");
495 element.setTextContent(textContent.toString());
499 * Writes identifier that consists of prefix and QName.
508 * Map of namespaces and prefixes.
510 private static void writeIdentifierWithNamespacePrefix(Element element,
511 StringBuilder textContent, QName qName, Map<String, String> prefixes) {
512 String namespace = qName.getNamespace().toString();
513 String prefix = prefixes.get(namespace);
514 if (prefix == null) {
515 prefix = qName.getPrefix();
516 if (prefix == null || prefix.isEmpty()
517 || prefixes.containsValue(prefix)) {
518 prefix = generateNewPrefix(prefixes.values());
522 element.setAttribute("xmlns:" + prefix, namespace.toString());
523 textContent.append(prefix);
524 prefixes.put(namespace, prefix);
526 textContent.append(":");
527 textContent.append(qName.getLocalName());
531 * Generates new prefix which consists of four random characters <a-z>.
534 * Collection of prefixes.
535 * @return New prefix which consists of four random characters <a-z>.
537 private static String generateNewPrefix(Collection<String> prefixes) {
538 StringBuilder result = null;
539 Random random = new Random();
541 result = new StringBuilder();
542 for (int i = 0; i < 4; i++) {
543 int randomNumber = 0x61 + (Math.abs(random.nextInt()) % 26);
544 result.append(Character.toChars(randomNumber));
546 } while (prefixes.contains(result.toString()));
548 return result.toString();
552 * Gets path pointed to data in data store.
554 * @return Path pointed to data in data store.
556 public InstanceIdentifier getPath() {
561 * Sets {@link ListenerRegistration} registration.
563 * @param registration
564 * ListenerRegistration<DataChangeListener>
566 public void setRegistration(
567 ListenerRegistration<DataChangeListener> registration) {
568 this.registration = registration;
572 * Gets the name of the stream.
574 * @return The name of the stream.
576 public String getStreamName() {
581 * Removes all subscribers and unregisters event bus change recorder form
584 public void close() throws Exception {
585 subscribers = new ConcurrentSet<>();
586 registration.close();
588 eventBus.unregister(eventBusChangeRecorder);
592 * Checks if {@link ListenerRegistration} registration exist.
594 * @return True if exist, false otherwise.
596 public boolean isListening() {
597 return registration == null ? false : true;
601 * Creates event of type {@link EventType#REGISTER}, set {@link Channel}
602 * subscriber to the event and post event into event bus.
607 public void addSubscriber(Channel subscriber) {
608 if (!subscriber.isActive()) {
609 logger.debug("Channel is not active between websocket server and subscriber {}"
610 + subscriber.remoteAddress());
612 Event event = new Event(EventType.REGISTER);
613 event.setSubscriber(subscriber);
614 eventBus.post(event);
618 * Creates event of type {@link EventType#DEREGISTER}, sets {@link Channel}
619 * subscriber to the event and posts event into event bus.
623 public void removeSubscriber(Channel subscriber) {
624 logger.debug("Subscriber {} is removed.", subscriber.remoteAddress());
625 Event event = new Event(EventType.DEREGISTER);
626 event.setSubscriber(subscriber);
627 eventBus.post(event);
631 * Checks if exists at least one {@link Channel} subscriber.
633 * @return True if exist at least one {@link Channel} subscriber, false
636 public boolean hasSubscribers() {
637 return !subscribers.isEmpty();
641 * Consists of two types {@link Store#CONFIG} and {@link Store#OPERATION}.
643 private static enum Store {
644 CONFIG("config"), OPERATION("operation");
646 private final String value;
648 private Store(String value) {
654 * Consists of three types {@link Operation#CREATED},
655 * {@link Operation#UPDATED} and {@link Operation#DELETED}.
657 private static enum Operation {
658 CREATED("created"), UPDATED("updated"), DELETED("deleted");
660 private final String value;
662 private Operation(String value) {