/*
* 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.catalina.valves.rewrite;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import org.apache.tomcat.util.file.ConfigFileLoader;
import org.apache.tomcat.util.file.ConfigurationSource.Resource;
import org.apache.tomcat.util.res.StringManager;
/**
* Implement a map for the txt: and rnd: mod_rewrite capabilities.
*/
public class RandomizedTextRewriteMap implements RewriteMap {
protected static final StringManager sm = StringManager.getManager(RandomizedTextRewriteMap.class);
private static final Random random = new Random();
private final Map<String,String[]> map = new HashMap<>();
/**
* Create a map from a text file according to the mod_rewrite syntax.
*
* @param txtFilePath the text file path
* @param useRandom if the map should produce random results
*/
public RandomizedTextRewriteMap(String txtFilePath, boolean useRandom) {
String line;
try (Resource txtResource = ConfigFileLoader.getSource().getResource(txtFilePath);
BufferedReader reader = new BufferedReader(new InputStreamReader(txtResource.getInputStream()))) {
while ((line = reader.readLine()) != null) {
if (line.startsWith("#") || line.isEmpty()) {
// Ignore comment line or empty lines
continue;
} else if (line.indexOf('#') > 0) {
// Ignore comment characters after '#'
line = line.substring(0, line.indexOf('#')).trim();
}
String[] keyValuePair = line.split(" ", 2);
if (keyValuePair.length > 1) {
String key = keyValuePair[0];
String value = keyValuePair[1];
String[] possibleValues;
if (useRandom && value.contains("|")) {
possibleValues = value.split("\\|");
} else {
possibleValues = new String[1];
possibleValues[0] = value;
}
map.put(key, possibleValues);
} else {
throw new IllegalArgumentException(sm.getString("rewriteMap.txtInvalidLine", line, txtFilePath));
}
}
} catch (IOException ioe) {
throw new IllegalArgumentException(sm.getString("rewriteMap.txtReadError", txtFilePath), ioe);
}
}
@Override
public String setParameters(String params) {
throw new IllegalArgumentException(
StringManager.getManager(RewriteMap.class).getString("rewriteMap.tooManyParameters"));
}
@Override
public String lookup(String key) {
String[] possibleValues = map.get(key);
if (possibleValues != null) {
if (possibleValues.length > 1) {
return possibleValues[random.nextInt(possibleValues.length)];
} else {
return possibleValues[0];
}
}
return null;
}
}