2 * Copyright (c) 2016 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.restconf.nb.rfc8040.streams.listeners;
10 import com.google.common.annotations.VisibleForTesting;
11 import com.google.common.base.Preconditions;
12 import java.io.StringReader;
13 import java.time.Instant;
14 import java.util.Optional;
15 import javax.xml.XMLConstants;
16 import javax.xml.parsers.DocumentBuilderFactory;
17 import javax.xml.parsers.ParserConfigurationException;
18 import javax.xml.xpath.XPath;
19 import javax.xml.xpath.XPathConstants;
20 import javax.xml.xpath.XPathFactory;
21 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
22 import org.w3c.dom.Document;
23 import org.xml.sax.InputSource;
26 * Features of query parameters part of both notifications.
29 abstract class AbstractQueryParams extends AbstractNotificationsData {
30 // FIXME: BUG-7956: switch to using UntrustedXML
31 private static final DocumentBuilderFactory DBF;
34 final DocumentBuilderFactory f = DocumentBuilderFactory.newInstance();
35 f.setCoalescing(true);
36 f.setExpandEntityReferences(false);
37 f.setIgnoringElementContentWhitespace(true);
38 f.setIgnoringComments(true);
39 f.setXIncludeAware(false);
41 f.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
42 f.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
43 f.setFeature("http://xml.org/sax/features/external-general-entities", false);
44 f.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
45 } catch (final ParserConfigurationException e) {
46 throw new ExceptionInInitializerError(e);
51 // FIXME: these should be final
52 private Instant start = null;
53 private Instant stop = null;
54 private String filter = null;
55 private boolean leafNodesOnly = false;
58 public final Instant getStart() {
63 * Set query parameters for listener.
66 * start-time of getting notification
68 * stop-time of getting notification
70 * indicate which subset of all possible events are of interest
71 * @param leafNodesOnly
72 * if true, notifications will contain changes to leaf nodes only
74 @SuppressWarnings("checkstyle:hiddenField")
75 public void setQueryParams(final Instant start, final Optional<Instant> stop, final Optional<String> filter,
76 final boolean leafNodesOnly) {
77 this.start = Preconditions.checkNotNull(start);
78 this.stop = stop.orElse(null);
79 this.filter = filter.orElse(null);
80 this.leafNodesOnly = leafNodesOnly;
84 * Check whether this query should only notify about leaf node changes.
86 * @return true if this query should only notify about leaf node changes
88 public boolean getLeafNodesOnly() {
93 * Checking query parameters on specific notification.
95 * @param xml data of notification
96 * @param listener listener of notification
97 * @return true if notification meets the requirements of query parameters,
100 @SuppressWarnings("checkstyle:IllegalCatch")
101 protected <T extends BaseListenerInterface> boolean checkQueryParams(final String xml, final T listener) {
102 final Instant now = Instant.now();
103 if (this.stop != null) {
104 if ((this.start.compareTo(now) < 0) && (this.stop.compareTo(now) > 0)) {
105 return checkFilter(xml);
107 if (this.stop.compareTo(now) < 0) {
110 } catch (final Exception e) {
111 throw new RestconfDocumentedException("Problem with unregister listener." + e);
114 } else if (this.start != null) {
115 if (this.start.compareTo(now) < 0) {
117 return checkFilter(xml);
120 return checkFilter(xml);
126 * Check if is filter used and then prepare and post data do client.
128 * @param xml data of notification
130 @SuppressWarnings("checkstyle:IllegalCatch")
131 private boolean checkFilter(final String xml) {
132 if (this.filter == null) {
137 return parseFilterParam(xml);
138 } catch (final Exception e) {
139 throw new RestconfDocumentedException("Problem while parsing filter.", e);
144 * Parse and evaluate filter value by xml.
146 * @return true or false - depends on filter expression and data of
148 * @throws Exception if operation fails
150 private boolean parseFilterParam(final String xml) throws Exception {
151 final Document docOfXml = DBF.newDocumentBuilder().parse(new InputSource(new StringReader(xml)));
152 final XPath xPath = XPathFactory.newInstance().newXPath();
153 // FIXME: BUG-7956: xPath.setNamespaceContext(nsContext);
154 return (boolean) xPath.compile(this.filter).evaluate(docOfXml, XPathConstants.BOOLEAN);