| /* |
| * 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.nutch.net.urlnormalizer.slash; |
| |
| import java.lang.invoke.MethodHandles; |
| import java.io.BufferedReader; |
| import java.io.FileReader; |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.StringReader; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.commons.lang.StringUtils; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.nutch.crawl.CrawlDatum; |
| import org.apache.nutch.net.URLNormalizer; |
| import org.apache.nutch.plugin.Extension; |
| import org.apache.nutch.plugin.PluginRepository; |
| |
| /** |
| * @author markus@openindex.io |
| */ |
| public class SlashURLNormalizer implements URLNormalizer { |
| |
| private Configuration conf; |
| |
| private static final Logger LOG = LoggerFactory |
| .getLogger(MethodHandles.lookup().lookupClass()); |
| |
| private static final char QUESTION_MARK = '?'; |
| private static final char SLASH = '/'; |
| private static final char DOT = '.'; |
| private static final String PROTOCOL_DELIMITER = "://"; |
| |
| private static String attributeFile = null; |
| private String slashesFile = null; |
| |
| // We record a map of hosts and boolean, the boolean denotes whether the host should |
| // have slashes after URL paths. True means slash, false means remove the slash |
| private static final Map<String,Boolean> slashesMap = new HashMap<>(); |
| |
| public SlashURLNormalizer() { |
| //default constructor |
| } |
| |
| public SlashURLNormalizer(String slashesFile) { |
| this.slashesFile = slashesFile; |
| } |
| |
| private synchronized void readConfiguration(Reader configReader) throws IOException { |
| if (slashesMap.size() > 0) { |
| return; |
| } |
| |
| BufferedReader reader = new BufferedReader(configReader); |
| String line, host; |
| String rule; |
| int delimiterIndex; |
| |
| while ((line = reader.readLine()) != null) { |
| if (StringUtils.isNotBlank(line) && !line.startsWith("#")) { |
| line = line.trim(); |
| delimiterIndex = line.indexOf(" "); |
| // try tabulator |
| if (delimiterIndex == -1) { |
| delimiterIndex = line.indexOf("\t"); |
| } |
| |
| host = line.substring(0, delimiterIndex); |
| rule = line.substring(delimiterIndex + 1).trim(); |
| |
| if (rule.equals("+")) { |
| slashesMap.put(host, true); |
| } else { |
| slashesMap.put(host, false); |
| } |
| } |
| } |
| } |
| |
| public Configuration getConf() { |
| return conf; |
| } |
| |
| public void setConf(Configuration conf) { |
| this.conf = conf; |
| |
| // get the extensions for domain urlfilter |
| String pluginName = "urlnormalizer-slash"; |
| Extension[] extensions = PluginRepository.get(conf).getExtensionPoint( |
| URLNormalizer.class.getName()).getExtensions(); |
| for (int i = 0; i < extensions.length; i++) { |
| Extension extension = extensions[i]; |
| if (extension.getDescriptor().getPluginId().equals(pluginName)) { |
| attributeFile = extension.getAttribute("file"); |
| break; |
| } |
| } |
| |
| // handle blank non empty input |
| if (attributeFile != null && attributeFile.trim().equals("")) { |
| attributeFile = null; |
| } |
| |
| if (attributeFile != null) { |
| if (LOG.isInfoEnabled()) { |
| LOG.info("Attribute \"file\" is defined for plugin " + pluginName |
| + " as " + attributeFile); |
| } |
| } |
| else { |
| if (LOG.isWarnEnabled()) { |
| LOG.warn("Attribute \"file\" is not defined in plugin.xml for plugin " |
| + pluginName); |
| } |
| } |
| |
| // domain file and attribute "file" take precedence if defined |
| String file = conf.get("urlnormalizer.slashes.file"); |
| String stringRules = conf.get("urlnormalizer.slashes.rules"); |
| if (slashesFile != null) { |
| file = slashesFile; |
| } |
| else if (attributeFile != null) { |
| file = attributeFile; |
| } |
| Reader reader = null; |
| if (stringRules != null) { // takes precedence over files |
| reader = new StringReader(stringRules); |
| } else { |
| reader = conf.getConfResourceAsReader(file); |
| } |
| try { |
| if (reader == null) { |
| reader = new FileReader(file); |
| } |
| readConfiguration(reader); |
| } |
| catch (IOException e) { |
| LOG.error(org.apache.hadoop.util.StringUtils.stringifyException(e)); |
| } |
| } |
| |
| public String normalize(String url, String scope) throws MalformedURLException { |
| return normalize(url, null, scope); |
| } |
| |
| public String normalize(String url, CrawlDatum crawlDatum, String scope) throws MalformedURLException { |
| // Get URL repr. |
| URL u = new URL(url); |
| |
| // Get the host |
| String host = u.getHost(); |
| |
| // Do we have a rule for this host? |
| if (slashesMap.containsKey(host)) { |
| // Yes, separate the path and optional querystring |
| String protocol = u.getProtocol(); |
| String path = u.getPath(); |
| |
| // Don't do anything to root URL's |
| // / is always set by basic normalizer |
| if (path.length() > 1) { |
| String queryString = u.getQuery(); |
| |
| // Get the rule |
| boolean rule = slashesMap.get(host); |
| |
| // Does it have a trailing slash |
| int lastIndexOfSlash = path.lastIndexOf(SLASH); |
| boolean trailingSlash = (lastIndexOfSlash == path.length() - 1); |
| |
| // Do we need to add a trailing slash? |
| if (!trailingSlash && rule) { |
| // Only add a trailing slash if this path doesn't appear to have an extension/suffix such as .html |
| int lastIndexOfDot = path.lastIndexOf(DOT); |
| if (path.length() < 6 || lastIndexOfDot == -1 || lastIndexOfDot < path.length() - 6) { |
| StringBuilder buffer = new StringBuilder(protocol); |
| buffer.append(PROTOCOL_DELIMITER); |
| buffer.append(host); |
| buffer.append(path); |
| buffer.append(SLASH); |
| if (queryString != null) { |
| buffer.append(QUESTION_MARK); |
| buffer.append(queryString); |
| } |
| url = buffer.toString(); |
| } |
| } |
| |
| // Do we need to remove a trailing slash? |
| else if (trailingSlash && !rule) { |
| StringBuilder buffer = new StringBuilder(protocol); |
| buffer.append(PROTOCOL_DELIMITER); |
| buffer.append(host); |
| buffer.append(path.substring(0, lastIndexOfSlash)); |
| if (queryString != null) { |
| buffer.append(QUESTION_MARK); |
| buffer.append(queryString); |
| } |
| url = buffer.toString(); |
| } |
| } |
| } |
| |
| return url; |
| } |
| } |