2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.sal.streams.listeners;
10 import com.google.common.base.Charsets;
11 import com.google.common.base.Preconditions;
12 import com.google.common.eventbus.AsyncEventBus;
13 import com.google.common.eventbus.EventBus;
14 import com.google.common.eventbus.Subscribe;
15 import io.netty.channel.Channel;
16 import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
17 import io.netty.util.internal.ConcurrentSet;
18 import java.io.ByteArrayOutputStream;
19 import java.io.OutputStreamWriter;
20 import java.io.UnsupportedEncodingException;
21 import java.text.SimpleDateFormat;
22 import java.util.Collection;
23 import java.util.Date;
24 import java.util.HashMap;
26 import java.util.Map.Entry;
27 import java.util.Random;
29 import java.util.concurrent.Executors;
30 import java.util.regex.Pattern;
31 import javax.activation.UnsupportedDataTypeException;
32 import javax.xml.parsers.DocumentBuilder;
33 import javax.xml.parsers.DocumentBuilderFactory;
34 import javax.xml.parsers.ParserConfigurationException;
35 import javax.xml.transform.OutputKeys;
36 import javax.xml.transform.Transformer;
37 import javax.xml.transform.TransformerException;
38 import javax.xml.transform.TransformerFactory;
39 import javax.xml.transform.dom.DOMSource;
40 import javax.xml.transform.stream.StreamResult;
41 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeEvent;
42 import org.opendaylight.controller.md.sal.dom.api.DOMDataChangeListener;
43 import org.opendaylight.controller.sal.rest.impl.XmlMapper;
44 import org.opendaylight.controller.sal.restconf.impl.ControllerContext;
45 import org.opendaylight.yangtools.concepts.ListenerRegistration;
46 import org.opendaylight.yangtools.yang.common.QName;
47 import org.opendaylight.yangtools.yang.data.api.CompositeNode;
48 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
49 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
50 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
51 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
52 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
53 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
54 import org.slf4j.Logger;
55 import org.slf4j.LoggerFactory;
56 import org.w3c.dom.Document;
57 import org.w3c.dom.Element;
58 import org.w3c.dom.Node;
61 * {@link ListenerAdapter} is responsible to track events, which occurred by changing data in data source.
63 public class ListenerAdapter implements DOMDataChangeListener {
65 private static final Logger LOG = LoggerFactory.getLogger(ListenerAdapter.class);
66 private static final DocumentBuilderFactory DBF = DocumentBuilderFactory.newInstance();
67 private static final TransformerFactory FACTORY = TransformerFactory.newInstance();
68 private static final Pattern RFC3339_PATTERN = Pattern.compile("(\\d\\d)(\\d\\d)$");
70 private final XmlMapper xmlMapper = new XmlMapper();
71 private final SimpleDateFormat rfc3339 = new SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ssZ");
73 private final YangInstanceIdentifier path;
74 private ListenerRegistration<DOMDataChangeListener> registration;
75 private final String streamName;
76 private Set<Channel> subscribers = new ConcurrentSet<>();
77 private final EventBus eventBus;
78 private final EventBusChangeRecorder eventBusChangeRecorder;
81 * Creates new {@link ListenerAdapter} listener specified by path and stream name.
84 * Path to data in data store.
86 * The name of the stream.
88 ListenerAdapter(final YangInstanceIdentifier path, final String streamName) {
89 Preconditions.checkNotNull(path);
90 Preconditions.checkArgument(streamName != null && !streamName.isEmpty());
92 this.streamName = streamName;
93 eventBus = new AsyncEventBus(Executors.newSingleThreadExecutor());
94 eventBusChangeRecorder = new EventBusChangeRecorder();
95 eventBus.register(eventBusChangeRecorder);
99 public void onDataChanged(final AsyncDataChangeEvent<YangInstanceIdentifier, NormalizedNode<?, ?>> change) {
100 // TODO Auto-generated method stub
102 if (!change.getCreatedData().isEmpty() || !change.getUpdatedData().isEmpty()
103 || !change.getRemovedPaths().isEmpty()) {
104 final String xml = prepareXmlFrom(change);
105 final Event event = new Event(EventType.NOTIFY);
107 eventBus.post(event);
112 * Tracks events of data change by customer.
114 private final class EventBusChangeRecorder {
116 public void recordCustomerChange(final Event event) {
117 if (event.getType() == EventType.REGISTER) {
118 final Channel subscriber = event.getSubscriber();
119 if (!subscribers.contains(subscriber)) {
120 subscribers.add(subscriber);
122 } else if (event.getType() == EventType.DEREGISTER) {
123 subscribers.remove(event.getSubscriber());
124 Notificator.removeListenerIfNoSubscriberExists(ListenerAdapter.this);
125 } else if (event.getType() == EventType.NOTIFY) {
126 for (final Channel subscriber : subscribers) {
127 if (subscriber.isActive()) {
128 LOG.debug("Data are sent to subscriber {}:", subscriber.remoteAddress());
129 subscriber.writeAndFlush(new TextWebSocketFrame(event.getData()));
131 LOG.debug("Subscriber {} is removed - channel is not active yet.", subscriber.remoteAddress());
132 subscribers.remove(subscriber);
140 * Represents event of specific {@link EventType} type, holds data and {@link Channel} subscriber.
142 private final class Event {
143 private final EventType type;
144 private Channel subscriber;
148 * Creates new event specified by {@link EventType} type.
153 public Event(final EventType type) {
158 * Gets the {@link Channel} subscriber.
162 public Channel getSubscriber() {
167 * Sets subscriber for event.
172 public void setSubscriber(final Channel subscriber) {
173 this.subscriber = subscriber;
179 * @return String representation of event data.
181 public String getData() {
191 public void setData(final String data) {
198 * @return The type of the event.
200 public EventType getType() {
208 private enum EventType {
215 * Prepare data in printable form and transform it to String.
219 * @return Data in printable form.
221 private String prepareXmlFrom(final AsyncDataChangeEvent<YangInstanceIdentifier, NormalizedNode<?, ?>> change) {
222 final Document doc = createDocument();
223 final Element notificationElement = doc.createElementNS("urn:ietf:params:xml:ns:netconf:notification:1.0",
225 doc.appendChild(notificationElement);
227 final Element eventTimeElement = doc.createElement("eventTime");
228 eventTimeElement.setTextContent(toRFC3339(new Date()));
229 notificationElement.appendChild(eventTimeElement);
231 final Element dataChangedNotificationEventElement = doc.createElementNS(
232 "urn:opendaylight:params:xml:ns:yang:controller:md:sal:remote", "data-changed-notification");
233 addValuesToDataChangedNotificationEventElement(doc, dataChangedNotificationEventElement, change);
234 notificationElement.appendChild(dataChangedNotificationEventElement);
237 final ByteArrayOutputStream out = new ByteArrayOutputStream();
238 final Transformer transformer = FACTORY.newTransformer();
239 transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
240 transformer.setOutputProperty(OutputKeys.METHOD, "xml");
241 transformer.setOutputProperty(OutputKeys.INDENT, "yes");
242 transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
243 transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
244 transformer.transform(new DOMSource(doc), new StreamResult(new OutputStreamWriter(out, Charsets.UTF_8)));
245 final byte[] charData = out.toByteArray();
246 return new String(charData, "UTF-8");
247 } catch (TransformerException | UnsupportedEncodingException e) {
248 final String msg = "Error during transformation of Document into String";
255 * Formats data specified by RFC3339.
259 * @return Data specified by RFC3339.
261 private String toRFC3339(final Date d) {
262 return RFC3339_PATTERN.matcher(rfc3339.format(d)).replaceAll("$1:$2");
266 * Creates {@link Document} document.
267 * @return {@link Document} document.
269 private Document createDocument() {
270 final DocumentBuilder bob;
272 bob = DBF.newDocumentBuilder();
273 } catch (final ParserConfigurationException e) {
276 return bob.newDocument();
280 * Adds values to data changed notification event element.
284 * @param dataChangedNotificationEventElement
287 * {@link DataChangeEvent}
289 private void addValuesToDataChangedNotificationEventElement(final Document doc,
290 final Element dataChangedNotificationEventElement,
291 final AsyncDataChangeEvent<YangInstanceIdentifier, NormalizedNode<?, ?>> change) {
292 addValuesFromDataToElement(doc, change.getCreatedData().keySet(), dataChangedNotificationEventElement,
294 if (change.getCreatedData().isEmpty()) {
295 addValuesFromDataToElement(doc, change.getUpdatedData().keySet(), dataChangedNotificationEventElement,
298 addValuesFromDataToElement(doc, change.getRemovedPaths(), dataChangedNotificationEventElement,
303 * Adds values from data to element.
308 * Set of {@link YangInstanceIdentifier}.
316 private void addValuesFromDataToElement(final Document doc, final Set<YangInstanceIdentifier> data, final Element element,
317 final Operation operation) {
318 if (data == null || data.isEmpty()) {
321 for (final YangInstanceIdentifier path : data) {
322 final Node node = createDataChangeEventElement(doc, path, null, operation);
323 element.appendChild(node);
328 * Adds values from data to element.
333 * Map of {@link YangInstanceIdentifier} and {@link CompositeNode}.
341 private void addValuesFromDataToElement(final Document doc, final Map<YangInstanceIdentifier, CompositeNode> data, final Element element,
342 final Operation operation) {
343 if (data == null || data.isEmpty()) {
346 for (final Entry<YangInstanceIdentifier, CompositeNode> entry : data.entrySet()) {
347 final Node node = createDataChangeEventElement(doc, entry.getKey(), entry.getValue(), operation);
348 element.appendChild(node);
353 * Creates changed event element from data.
358 * Path to data in data store.
360 * {@link CompositeNode}
365 * @return {@link Node} node represented by changed event element.
367 private Node createDataChangeEventElement(final Document doc, final YangInstanceIdentifier path, final CompositeNode data,
368 final Operation operation) {
369 final Element dataChangeEventElement = doc.createElement("data-change-event");
370 final Element pathElement = doc.createElement("path");
371 addPathAsValueToElement(path, pathElement);
372 dataChangeEventElement.appendChild(pathElement);
374 // Element storeElement = doc.createElement("store");
375 // storeElement.setTextContent(store.value);
376 // dataChangeEventElement.appendChild(storeElement);
378 final Element operationElement = doc.createElement("operation");
379 operationElement.setTextContent(operation.value);
380 dataChangeEventElement.appendChild(operationElement);
383 final Element dataElement = doc.createElement("data");
384 final Node dataAnyXml = translateToXml(path, data);
385 final Node adoptedNode = doc.adoptNode(dataAnyXml);
386 dataElement.appendChild(adoptedNode);
387 dataChangeEventElement.appendChild(dataElement);
390 return dataChangeEventElement;
394 * Translates {@link CompositeNode} data to XML format.
397 * Path to data in data store.
399 * {@link CompositeNode}
400 * @return Data in XML format.
402 private Node translateToXml(final YangInstanceIdentifier path, final CompositeNode data) {
403 final DataNodeContainer schemaNode = ControllerContext.getInstance().getDataNodeContainerFor(path);
404 if (schemaNode == null) {
406 "Path '{}' contains node with unsupported type (supported type is Container or List) or some node was not found.",
411 final Document xml = xmlMapper.write(data, schemaNode);
412 return xml.getFirstChild();
413 } catch (final UnsupportedDataTypeException e) {
414 LOG.error("Error occured during translation of notification to XML.", e);
420 * Adds path as value to element.
423 * Path to data in data store.
427 private void addPathAsValueToElement(final YangInstanceIdentifier path, final Element element) {
428 // Map< key = namespace, value = prefix>
429 final Map<String, String> prefixes = new HashMap<>();
430 final YangInstanceIdentifier instanceIdentifier = path;
431 final StringBuilder textContent = new StringBuilder();
433 // FIXME: BUG-1281: this is duplicated code from yangtools (BUG-1275)
434 for (final PathArgument pathArgument : instanceIdentifier.getPathArguments()) {
435 textContent.append("/");
436 writeIdentifierWithNamespacePrefix(element, textContent, pathArgument.getNodeType(), prefixes);
437 if (pathArgument instanceof NodeIdentifierWithPredicates) {
438 final Map<QName, Object> predicates = ((NodeIdentifierWithPredicates) pathArgument).getKeyValues();
439 for (final QName keyValue : predicates.keySet()) {
440 final String predicateValue = String.valueOf(predicates.get(keyValue));
441 textContent.append("[");
442 writeIdentifierWithNamespacePrefix(element, textContent, keyValue, prefixes);
443 textContent.append("='");
444 textContent.append(predicateValue);
445 textContent.append("'");
446 textContent.append("]");
448 } else if (pathArgument instanceof NodeWithValue) {
449 textContent.append("[.='");
450 textContent.append(((NodeWithValue) pathArgument).getValue());
451 textContent.append("'");
452 textContent.append("]");
455 element.setTextContent(textContent.toString());
459 * Writes identifier that consists of prefix and QName.
468 * Map of namespaces and prefixes.
470 private static void writeIdentifierWithNamespacePrefix(final Element element, final StringBuilder textContent,
471 final QName qName, final Map<String, String> prefixes) {
472 final String namespace = qName.getNamespace().toString();
473 String prefix = prefixes.get(namespace);
474 if (prefix == null) {
475 prefix = generateNewPrefix(prefixes.values());
478 element.setAttribute("xmlns:" + prefix, namespace);
479 textContent.append(prefix);
480 prefixes.put(namespace, prefix);
482 textContent.append(":");
483 textContent.append(qName.getLocalName());
487 * Generates new prefix which consists of four random characters <a-z>.
490 * Collection of prefixes.
491 * @return New prefix which consists of four random characters <a-z>.
493 private static String generateNewPrefix(final Collection<String> prefixes) {
494 StringBuilder result = null;
495 final Random random = new Random();
497 result = new StringBuilder();
498 for (int i = 0; i < 4; i++) {
499 final int randomNumber = 0x61 + (Math.abs(random.nextInt()) % 26);
500 result.append(Character.toChars(randomNumber));
502 } while (prefixes.contains(result.toString()));
504 return result.toString();
508 * Gets path pointed to data in data store.
510 * @return Path pointed to data in data store.
512 public YangInstanceIdentifier getPath() {
517 * Sets {@link ListenerRegistration} registration.
519 * @param registration
520 * ListenerRegistration<DataChangeListener>
522 public void setRegistration(final ListenerRegistration<DOMDataChangeListener> registration) {
523 this.registration = registration;
527 * Gets the name of the stream.
529 * @return The name of the stream.
531 public String getStreamName() {
536 * Removes all subscribers and unregisters event bus change recorder form event bus.
538 public void close() throws Exception {
539 subscribers = new ConcurrentSet<>();
540 registration.close();
542 eventBus.unregister(eventBusChangeRecorder);
546 * Checks if {@link ListenerRegistration} registration exist.
548 * @return True if exist, false otherwise.
550 public boolean isListening() {
551 return registration == null ? false : true;
555 * Creates event of type {@link EventType#REGISTER}, set {@link Channel} subscriber to the event and post event into
561 public void addSubscriber(final Channel subscriber) {
562 if (!subscriber.isActive()) {
563 LOG.debug("Channel is not active between websocket server and subscriber {}" + subscriber.remoteAddress());
565 final Event event = new Event(EventType.REGISTER);
566 event.setSubscriber(subscriber);
567 eventBus.post(event);
571 * Creates event of type {@link EventType#DEREGISTER}, sets {@link Channel} subscriber to the event and posts event
576 public void removeSubscriber(final Channel subscriber) {
577 LOG.debug("Subscriber {} is removed.", subscriber.remoteAddress());
578 final Event event = new Event(EventType.DEREGISTER);
579 event.setSubscriber(subscriber);
580 eventBus.post(event);
584 * Checks if exists at least one {@link Channel} subscriber.
586 * @return True if exist at least one {@link Channel} subscriber, false otherwise.
588 public boolean hasSubscribers() {
589 return !subscribers.isEmpty();
593 * Consists of two types {@link Store#CONFIG} and {@link Store#OPERATION}.
595 private static enum Store {
597 OPERATION("operation");
599 private final String value;
601 private Store(final String value) {
607 * Consists of three types {@link Operation#CREATED}, {@link Operation#UPDATED} and {@link Operation#DELETED}.
609 private static enum Operation {
614 private final String value;
616 private Operation(final String value) {