1 /**
2 * This file Copyright (c) 2003-2010 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.cms.taglibs.util;
35
36 import info.magnolia.cms.core.Content;
37 import info.magnolia.cms.core.ItemType;
38 import info.magnolia.cms.core.NodeData;
39
40 import java.io.IOException;
41 import java.util.ArrayList;
42 import java.util.Collection;
43 import java.util.Iterator;
44 import java.util.regex.Pattern;
45
46 import javax.jcr.PropertyType;
47 import javax.servlet.jsp.JspException;
48 import javax.servlet.jsp.JspWriter;
49 import javax.servlet.jsp.tagext.TagSupport;
50
51 import org.apache.commons.lang.ArrayUtils;
52 import org.apache.commons.lang.StringUtils;
53 import org.apache.commons.lang.exception.NestableRuntimeException;
54 import org.slf4j.Logger;
55 import org.slf4j.LoggerFactory;
56
57
58 /**
59 * Output a set of snippets taken from any paragraph in the given page mathing any of the search term.
60 * @jsp.tag name="searchResultSnippet" body-content="empty"
61 * @jsp.tag-example
62 * <cmsu:simplesearch query="${param.search}" var="results" />
63 * <c:forEach items="${results}" var="page">
64 * <cmsu:searchResultSnippet query="${param.search}" page="${page}" />
65 * </c:forEach>
66 *
67 * @author Fabrizio Giustina
68 * @version $Revision: 32667 $ ($Author: gjoseph $)
69 */
70 public class SearchResultSnippetTag extends TagSupport {
71 private static final Pattern HTML_STRIP = Pattern.compile("<.*?>", Pattern.DOTALL);
72
73 private static final Logger log = LoggerFactory.getLogger(SearchResultSnippetTag.class);
74
75 /**
76 * Start level.
77 */
78 private Content page;
79
80 /**
81 * Query, natural language.
82 */
83 private String query;
84
85 /**
86 * Number of chars to include in result.
87 */
88 private int chars = 100;
89
90 /**
91 * Maximum number of snippets to include in result.
92 */
93 private int maxSnippets = 3;
94
95 /**
96 * Search query.
97 * @jsp.attribute required="true" rtexprvalue="true"
98 */
99 public void setQuery(String query) {
100 this.query = query;
101 }
102
103 /**
104 * Number of characters to include in search snippets. Default is 100.
105 * @jsp.attribute required="false" rtexprvalue="true" type="int"
106 */
107 public void setChars(int chars) {
108 this.chars = chars;
109 }
110
111 /**
112 * Maximum number of snippets to print out.
113 * @jsp.attribute required="false" rtexprvalue="true" type="int"
114 */
115 public void setMaxSnippets(int maxSnippets) {
116 this.maxSnippets = maxSnippets;
117 }
118
119 /**
120 * A Content node of type mgnl:content (a magnolia page), typically returned by the simpleSearch tag.
121 * @jsp.attribute required="true" rtexprvalue="true" type="info.magnolia.cms.core.Content"
122 */
123 public void setPage(Content page) {
124 this.page = page;
125 }
126
127 /**
128 * @see javax.servlet.jsp.tagext.TagSupport#doStartTag()
129 */
130 public int doStartTag() throws JspException {
131
132 JspWriter out = this.pageContext.getOut();
133 try {
134 Iterator iterator = getSnippets().iterator();
135 while (iterator.hasNext()) {
136 out.println(iterator.next());
137 }
138 }
139 catch (IOException e) {
140 // should never happen
141 throw new NestableRuntimeException(e);
142 }
143 return EVAL_PAGE;
144 }
145
146 /**
147 * Extract a collection of snippets from any paragraph in the given page.
148 * @return a collection of Strings.
149 * @todo avoid overlapping snippets (use regexp insted of simple indexOfs)
150 * @todo only extract snippets from user-configured properties
151 * @todo abbreviate on whitespace and puntuation, detect start of sentences
152 * @todo replace ampersand in regexp
153 * @todo break methods and write junits
154 */
155 public Collection getSnippets() {
156
157 log.debug("collecting snippets"); //$NON-NLS-1$
158
159 Collection snippets = new ArrayList();
160 String[] searchTerms = StringUtils.split(this.query);
161
162 Collection paragraphCollections = this.page.getChildren(ItemType.CONTENTNODE);
163
164 Iterator iterator = paragraphCollections.iterator();
165 outer : while (iterator.hasNext()) {
166 Content paragraphCollection = (Content) iterator.next();
167
168 Collection paragraphs = paragraphCollection.getChildren();
169
170 Iterator parIterator = paragraphs.iterator();
171 while (parIterator.hasNext()) {
172 Content paragraph = (Content) parIterator.next();
173
174 log.debug("Iterating on paragraph {}", paragraph); //$NON-NLS-1$
175
176 Collection properties = paragraph.getNodeDataCollection();
177
178 Iterator dataIterator = properties.iterator();
179 while (dataIterator.hasNext()) {
180 NodeData property = (NodeData) dataIterator.next();
181 if (property.getType() != PropertyType.BINARY) {
182
183 String resultString = property.getString();
184
185 log.debug("Iterating on property {}", property.getName()); //$NON-NLS-1$
186 log.debug("Property value is {}", resultString); //$NON-NLS-1$
187
188 // a quick and buggy way to avoid configuration properties, we should allow the user to
189 // configure a list of nodeData to search for...
190 if (resultString.length() < 20) {
191 continue;
192 }
193
194 for (int j = 0; j < searchTerms.length; j++) {
195 String searchTerm = StringUtils.lowerCase(searchTerms[j]);
196
197 // exclude keywords and words with less than 2 chars
198 if (!ArrayUtils.contains(SimpleSearchTag.KEYWORDS, searchTerm) && searchTerm.length() > 2) {
199
200 log.debug("Looking for search term [{}] in [{}]", searchTerm, resultString); //$NON-NLS-1$
201
202 // first check, avoid using heavy string replaceAll operations if the search term is not
203 // there
204 if (!StringUtils.contains(resultString.toLowerCase(), searchTerm)) {
205 continue;
206 }
207
208 // strips out html tags using a regexp
209 resultString = stripHtmlTags(resultString);
210
211 // only get first matching keyword
212 int pos = resultString.toLowerCase().indexOf(searchTerm);
213 if (pos > -1) {
214
215 int posEnd = pos + searchTerm.length();
216 int from = (pos - chars / 2);
217 if (from < 0) {
218 from = 0;
219 }
220
221 int to = from + chars;
222 if (to > resultString.length()) {
223 to = resultString.length();
224 }
225
226 StringBuffer snippet = new StringBuffer();
227
228 snippet.append(StringUtils.substring(resultString, from, pos));
229 snippet.append("<strong>"); //$NON-NLS-1$
230 snippet.append(StringUtils.substring(resultString, pos, posEnd));
231 snippet.append("</strong>"); //$NON-NLS-1$
232 snippet.append(StringUtils.substring(resultString, posEnd, to));
233
234 if (from > 0) {
235 snippet.insert(0, "... "); //$NON-NLS-1$
236 }
237 if (to < resultString.length()) {
238 snippet.append("... "); //$NON-NLS-1$
239 }
240
241 log.debug("Search term found, adding snippet {}", snippet); //$NON-NLS-1$
242
243 snippets.add(snippet);
244 if (snippets.size() >= this.maxSnippets) {
245
246 log.debug("Maximum number of snippets ({}) reached, exiting", //$NON-NLS-1$
247 Integer.toString(this.maxSnippets));
248
249 break outer;
250 }
251 }
252 }
253 }
254 }
255 }
256 }
257 }
258
259 return snippets;
260 }
261
262 /**
263 * @param resultString
264 * @return
265 */
266 protected String stripHtmlTags(String input) {
267 return HTML_STRIP.matcher(input).replaceAll("");
268 }
269
270 /**
271 * @see javax.servlet.jsp.tagext.TagSupport#release()
272 */
273 public void release() {
274 this.query = null;
275 this.page = null;
276 this.chars = 100;
277 this.maxSnippets = 3;
278 super.release();
279 }
280
281 }