/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.jmeter.protocol.http.parser;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Iterator;
import org.apache.jmeter.protocol.http.util.ConversionUtils;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;
//NOTE: Also looked at using Java 1.4 regexp instead of ORO. The change was
//trivial. Performance did not improve -- at least not significantly.
//Finally decided for ORO following advise from Stefan Bodewig (message
//to jmeter-dev dated 25 Nov 2003 8:52 CET) [Jordi]
import org.apache.oro.text.MalformedCachePatternException;
import org.apache.oro.text.regex.MatchResult;
import org.apache.oro.text.regex.Pattern;
import org.apache.oro.text.regex.PatternMatcherInput;
import org.apache.oro.text.regex.Perl5Compiler;
import org.apache.oro.text.regex.Perl5Matcher;
/**
* HtmlParser implementation using regular expressions.
* <p>
* This class will find RLs specified in the following ways (where <b>url</b>
* represents the RL being found:
* <ul>
* <li><img src=<b>url</b> ... >
* <li><script src=<b>url</b> ... >
* <li><applet code=<b>url</b> ... >
* <li><input type=image src=<b>url</b> ... >
* <li><body background=<b>url</b> ... >
* <li><table background=<b>url</b> ... >
* <li><td background=<b>url</b> ... >
* <li><tr background=<b>url</b> ... >
* <li><applet ... codebase=<b>url</b> ... >
* <li><embed src=<b>url</b> ... >
* <li><embed codebase=<b>url</b> ... >
* <li><object codebase=<b>url</b> ... >
* <li><link rel=stylesheet href=<b>url</b>... gt;
* <li><bgsound src=<b>url</b> ... >
* <li><frame src=<b>url</b> ... >
* </ul>
*
* <p>
* This class will take into account the following construct:
* <ul>
* <li><base href=<b>url</b>>
* </ul>
*
* <p>
* But not the following:
* <ul>
* <li>< ... codebase=<b>url</b> ... >
* </ul>
*
*/
class RegexpHTMLParser extends HTMLParser {
private static final Logger log = LoggingManager.getLoggerForClass();
/**
* Regexp fragment matching a tag attribute's value (including the equals
* sign and any spaces before it). Note it matches unquoted values, which to
* my understanding, are not conformant to any of the HTML specifications,
* but are still quite common in the web and all browsers seem to understand
* them.
*/
private static final String VALUE = "\\s*=\\s*(?:\"([^\"]*)\"|'([^']*)'|([^\"'\\s>\\\\][^\\s>]*)(?=[\\s>]))";
// Note there's 3 capturing groups per value
/**
* Regexp fragment matching the separation between two tag attributes.
*/
private static final String SEP = "\\s(?:[^>]*\\s)?";
/**
* Regular expression used against the HTML code to find the URIs of images,
* etc.:
*/
private static final String REGEXP =
"<(?:" + "!--.*?-->"
+ "|BASE" + SEP + "HREF" + VALUE
+ "|(?:IMG|SCRIPT|FRAME|IFRAME|BGSOUND)" + SEP + "SRC" + VALUE
+ "|APPLET" + SEP + "CODE(?:BASE)?" + VALUE
+ "|(?:EMBED|OBJECT)" + SEP + "(?:SRC|CODEBASE|DATA)" + VALUE
+ "|(?:BODY|TABLE|TR|TD)" + SEP + "BACKGROUND" + VALUE
+ "|[^<]+?STYLE\\s*=['\"].*?URL\\(\\s*['\"](.+?)['\"]\\s*\\)"
+ "|INPUT(?:" + SEP + "(?:SRC" + VALUE
+ "|TYPE\\s*=\\s*(?:\"image\"|'image'|image(?=[\\s>])))){2,}"
+ "|LINK(?:" + SEP + "(?:HREF" + VALUE
+ "|REL\\s*=\\s*(?:\"stylesheet\"|'stylesheet'|stylesheet(?=[\\s>])))){2,}" + ")";
// Number of capturing groups possibly containing Base HREFs:
private static final int NUM_BASE_GROUPS = 3;
/**
* Thread-local input:
*/
private static final ThreadLocal<PatternMatcherInput> localInput =
new ThreadLocal<PatternMatcherInput>() {
@Override
protected PatternMatcherInput initialValue() {
return new PatternMatcherInput(new char[0]);
}
};
/**
* {@inheritDoc}
*/
@Override
protected boolean isReusable() {
return true;
}
/**
* Make sure to compile the regular expression upon instantiation:
*/
protected RegexpHTMLParser() {
super();
}
/**
* {@inheritDoc}
* @throws HTMLParseException
*/
@Override
public Iterator<URL> getEmbeddedResourceURLs(String userAgent, byte[] html, URL baseUrl, URLCollection urls, String encoding) throws HTMLParseException {
Pattern pattern= null;
Perl5Matcher matcher = null;
try {
matcher = JMeterUtils.getMatcher();
PatternMatcherInput input = localInput.get();
// TODO: find a way to avoid the cost of creating a String here --
// probably a new PatternMatcherInput working on a byte[] would do
// better.
input.setInput(new String(html, encoding));
pattern=JMeterUtils.getPatternCache().getPattern(
REGEXP,
Perl5Compiler.CASE_INSENSITIVE_MASK
| Perl5Compiler.SINGLELINE_MASK
| Perl5Compiler.READ_ONLY_MASK);
while (matcher.contains(input, pattern)) {
MatchResult match = matcher.getMatch();
String s;
if (log.isDebugEnabled()) {
log.debug("match groups " + match.groups() + " " + match.toString());
}
// Check for a BASE HREF:
for (int g = 1; g <= NUM_BASE_GROUPS && g <= match.groups(); g++) {
s = match.group(g);
if (s != null) {
if (log.isDebugEnabled()) {
log.debug("new baseUrl: " + s + " - " + baseUrl.toString());
}
try {
baseUrl = ConversionUtils.makeRelativeURL(baseUrl, s);
} catch (MalformedURLException e) {
// Doesn't even look like a URL?
// Maybe it isn't: Ignore the exception.
if (log.isDebugEnabled()) {
log.debug("Can't build base URL from RL " + s + " in page " + baseUrl, e);
}
}
}
}
for (int g = NUM_BASE_GROUPS + 1; g <= match.groups(); g++) {
s = match.group(g);
if (s != null) {
if (log.isDebugEnabled()) {
log.debug("group " + g + " - " + match.group(g));
}
urls.addURL(s, baseUrl);
}
}
}
return urls.iterator();
} catch (UnsupportedEncodingException e) {
throw new HTMLParseException(e.getMessage(), e);
} catch (MalformedCachePatternException e) {
throw new HTMLParseException(e.getMessage(), e);
} finally {
JMeterUtils.clearMatcherMemory(matcher, pattern);
}
}
}