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.netconf.util.messages;
11 import java.util.Objects;
12 import java.util.Optional;
13 import javax.xml.XMLConstants;
14 import org.opendaylight.netconf.api.DocumentedException;
15 import org.opendaylight.netconf.api.xml.XmlElement;
16 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
17 import org.opendaylight.netconf.api.xml.XmlUtil;
18 import org.opendaylight.netconf.util.mapping.AbstractNetconfOperation.OperationNameAndNamespace;
19 import org.slf4j.Logger;
20 import org.slf4j.LoggerFactory;
21 import org.w3c.dom.Attr;
22 import org.w3c.dom.Document;
23 import org.w3c.dom.Element;
24 import org.w3c.dom.Node;
27 * See <a href="http://tools.ietf.org/html/rfc6241#section-6">rfc6241</a> for details.
29 public final class SubtreeFilter {
30 private static final Logger LOG = LoggerFactory.getLogger(SubtreeFilter.class);
32 private SubtreeFilter() {
36 public static Document applyRpcSubtreeFilter(final Document requestDocument,
37 final Document rpcReply) throws DocumentedException {
38 OperationNameAndNamespace operationNameAndNamespace = new OperationNameAndNamespace(requestDocument);
39 if (XmlNetconfConstants.URN_IETF_PARAMS_XML_NS_NETCONF_BASE_1_0.equals(operationNameAndNamespace.getNamespace())
40 && XmlNetconfConstants.GET.equals(operationNameAndNamespace.getOperationName())
41 || XmlNetconfConstants.GET_CONFIG.equals(operationNameAndNamespace.getOperationName())) {
42 // process subtree filtering here, in case registered netconf operations do
43 // not implement filtering.
44 Optional<XmlElement> maybeFilter = operationNameAndNamespace.getOperationElement()
45 .getOnlyChildElementOptionally(XmlNetconfConstants.FILTER,
46 XmlNetconfConstants.URN_IETF_PARAMS_XML_NS_NETCONF_BASE_1_0);
47 if (maybeFilter.isEmpty()) {
50 XmlElement filter = maybeFilter.orElseThrow();
51 if (isSupported(filter)) {
54 return filtered(filter, rpcReply);
58 return rpcReply; // return identical document
62 * Filters notification content. If filter type isn't of type "subtree", returns unchanged notification content.
63 * If no match is found, absent is returned.
64 * @param filter filter
65 * @param notification notification
66 * @return document containing filtered notification content
67 * @throws DocumentedException if operation fails
69 public static Optional<Document> applySubtreeNotificationFilter(final XmlElement filter,
70 final Document notification) throws DocumentedException {
71 removeEventTimeNode(notification);
72 if (isSupported(filter)) {
73 return Optional.ofNullable(filteredNotification(filter, notification));
75 return Optional.of(extractNotificationContent(notification));
78 private static void removeEventTimeNode(final Document document) {
79 final Node eventTimeNode = document.getDocumentElement().getElementsByTagNameNS(XmlNetconfConstants
80 .URN_IETF_PARAMS_NETCONF_CAPABILITY_NOTIFICATION_1_0, XmlNetconfConstants.EVENT_TIME).item(0);
81 document.getDocumentElement().removeChild(eventTimeNode);
84 private static boolean isSupported(final XmlElement filter) {
85 return "subtree".equals(filter.getAttribute("type"))
86 || "subtree".equals(filter.getAttribute("type",
87 XmlNetconfConstants.URN_IETF_PARAMS_XML_NS_NETCONF_BASE_1_0));
90 private static Document extractNotificationContent(final Document notification) throws DocumentedException {
91 XmlElement root = XmlElement.fromDomElement(notification.getDocumentElement());
92 XmlElement content = root.getOnlyChildElement();
93 notification.removeChild(root.getDomElement());
94 notification.appendChild(content.getDomElement());
98 private static Document filteredNotification(final XmlElement filter,
99 final Document originalNotification) throws DocumentedException {
100 Document result = XmlUtil.newDocument();
101 XmlElement dataSrc = XmlElement.fromDomDocument(originalNotification);
102 Element dataDst = (Element) result.importNode(dataSrc.getDomElement(), false);
103 for (XmlElement filterChild : filter.getChildElements()) {
104 addSubtree2(filterChild, dataSrc.getOnlyChildElement(), XmlElement.fromDomElement(dataDst));
106 if (dataDst.getFirstChild() != null) {
107 result.appendChild(dataDst.getFirstChild());
113 private static Document filtered(final XmlElement filter, final Document originalReplyDocument)
114 throws DocumentedException {
115 Document result = XmlUtil.newDocument();
116 // even if filter is empty, copy /rpc/data
117 Element rpcReply = originalReplyDocument.getDocumentElement();
118 Node rpcReplyDst = result.importNode(rpcReply, false);
119 result.appendChild(rpcReplyDst);
120 XmlElement dataSrc = XmlElement.fromDomElement(rpcReply).getOnlyChildElement("data",
121 XmlNetconfConstants.URN_IETF_PARAMS_XML_NS_NETCONF_BASE_1_0);
122 Element dataDst = (Element) result.importNode(dataSrc.getDomElement(), false);
123 rpcReplyDst.appendChild(dataDst);
124 addSubtree(filter, dataSrc, XmlElement.fromDomElement(dataDst));
129 private static void addSubtree(final XmlElement filter, final XmlElement src, final XmlElement dst)
130 throws DocumentedException {
131 for (XmlElement srcChild : src.getChildElements()) {
132 for (XmlElement filterChild : filter.getChildElements()) {
133 addSubtree2(filterChild, srcChild, dst);
138 private static MatchingResult addSubtree2(final XmlElement filter, final XmlElement src,
139 final XmlElement dstParent) throws DocumentedException {
140 Document document = dstParent.getDomElement().getOwnerDocument();
141 MatchingResult matches = matches(src, filter);
142 if (matches != MatchingResult.NO_MATCH && matches != MatchingResult.CONTENT_MISMATCH) {
143 // copy srcChild to dst
144 boolean filterHasChildren = !filter.getChildElements().isEmpty();
145 // copy to depth if this is leaf of filter tree
146 Element copied = (Element) document.importNode(src.getDomElement(), !filterHasChildren);
147 boolean shouldAppend = !filterHasChildren;
148 if (filterHasChildren) { // this implies TAG_MATCH
149 // do the same recursively
150 int numberOfTextMatchingChildren = 0;
151 for (XmlElement srcChild : src.getChildElements()) {
152 for (XmlElement filterChild : filter.getChildElements()) {
153 MatchingResult childMatch =
154 addSubtree2(filterChild, srcChild, XmlElement.fromDomElement(copied));
155 if (childMatch == MatchingResult.CONTENT_MISMATCH) {
156 return MatchingResult.NO_MATCH;
158 if (childMatch == MatchingResult.CONTENT_MATCH) {
159 numberOfTextMatchingChildren++;
161 shouldAppend |= childMatch != MatchingResult.NO_MATCH;
164 // if only text matching child filters are specified..
165 if (numberOfTextMatchingChildren == filter.getChildElements().size()) {
166 // force all children to be added (to depth). This is done by copying parent node to depth.
167 // implies shouldAppend == true
168 copied = (Element) document.importNode(src.getDomElement(), true);
172 dstParent.getDomElement().appendChild(copied);
179 * Shallow compare src node to filter: tag name and namespace must match.
180 * If filter node has no children and has text content, it also must match.
182 private static MatchingResult matches(final XmlElement src, final XmlElement filter) throws DocumentedException {
183 MatchingResult result = null;
184 if (src.getName().equals(filter.getName()) && Objects.equals(src.namespace(), filter.namespace())) {
185 // match text content
186 Optional<String> maybeText = filter.getOnlyTextContentOptionally();
187 if (maybeText.isPresent()) {
188 if (maybeText.equals(src.getOnlyTextContentOptionally()) || prefixedContentMatches(filter, src)) {
189 result = MatchingResult.CONTENT_MATCH;
191 result = MatchingResult.CONTENT_MISMATCH;
194 // match attributes, combination of content and tag is not supported
195 if (result == null) {
196 for (Attr attr : filter.getAttributes().values()) {
197 // ignore namespace declarations
198 if (!XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(attr.getNamespaceURI())) {
199 // find attr with matching localName(), namespaceURI(), == value() in src
200 String found = src.getAttribute(attr.getLocalName(), attr.getNamespaceURI());
201 if (attr.getValue().equals(found) && result != MatchingResult.NO_MATCH) {
202 result = MatchingResult.TAG_MATCH;
204 result = MatchingResult.NO_MATCH;
209 if (result == null) {
210 result = MatchingResult.TAG_MATCH;
213 if (result == null) {
214 result = MatchingResult.NO_MATCH;
216 LOG.debug("Matching {} to {} resulted in {}", src, filter, result);
220 private static boolean prefixedContentMatches(final XmlElement filter,
221 final XmlElement src) throws DocumentedException {
222 final Map.Entry<String, String> prefixToNamespaceOfFilter;
223 final Map.Entry<String, String> prefixToNamespaceOfSrc;
225 prefixToNamespaceOfFilter = filter.findNamespaceOfTextContent();
226 prefixToNamespaceOfSrc = src.findNamespaceOfTextContent();
227 } catch (IllegalArgumentException e) {
228 //if we can't find namespace of prefix - it's not a prefix, so it doesn't match
232 final String prefix = prefixToNamespaceOfFilter.getKey();
233 // If this is not a prefixed content, we do not need to continue since content do not match
234 if (prefix.equals(XmlElement.DEFAULT_NAMESPACE_PREFIX)) {
237 // Namespace mismatch
238 if (!prefixToNamespaceOfFilter.getValue().equals(prefixToNamespaceOfSrc.getValue())) {
242 final String unprefixedFilterContent =
243 filter.getTextContent().substring(prefixToNamespaceOfFilter.getKey().length() + 1);
244 final String unprefixedSrcContnet =
245 src.getTextContent().substring(prefixToNamespaceOfSrc.getKey().length() + 1);
246 // Finally compare unprefixed content
247 return unprefixedFilterContent.equals(unprefixedSrcContnet);
250 enum MatchingResult {
251 NO_MATCH, TAG_MATCH, CONTENT_MATCH, CONTENT_MISMATCH