1 package org.apache.turbine.util;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.Date;
23 import java.util.Locale;
24 import java.util.TimeZone;
25 import java.util.regex.Matcher;
26 import java.util.regex.Pattern;
27
28 import org.apache.commons.lang3.time.FastDateFormat;
29 import org.apache.turbine.Turbine;
30 import org.apache.turbine.pipeline.PipelineData;
31
32 import jakarta.servlet.http.HttpServletResponse;
33
34 /**
35 * This class provides utilities for handling some semi-trivial HTTP stuff that
36 * would otherwise be handled elsewhere.
37 *
38 * @author <a href="mailto:magnus@handpoint.com">Magnús Þór Torfason</a>
39 * @version $Id$
40 */
41 public class HttpUtils
42 {
43 /**
44 * Characters not allowed in external keys (name), that is not alphanumeric, underscore, hyphen, slash and dot.
45 * Validates only external key (name), as internal key may also contain colon and space.
46 */
47 private static final String CHARACTERS_NOT_ALLOWED_IN_KEY = "[^\\w_/\\.-]";
48
49 private static final Pattern CNAIK_PATTERN = Pattern.compile(CHARACTERS_NOT_ALLOWED_IN_KEY);
50 /**
51 * The date format to use for HTTP Dates.
52 */
53 private static FastDateFormat httpDateFormat = FastDateFormat.getInstance(
54 "EEE, dd MMM yyyy HH:mm:ss z",
55 TimeZone.getTimeZone("GMT"),
56 Locale.US);
57
58 /**
59 * Formats a java Date according to rfc 1123, the rfc standard for dates in
60 * http.
61 *
62 * @param date The Date to format
63 * @return A String representation of the date
64 */
65 public static String formatHttpDate(Date date)
66 {
67 return httpDateFormat.format(date);
68 }
69
70 /**
71 * This method sets the required expiration headers in the response for a
72 * given {@link PipelineData} object. This method attempts to set all relevant headers,
73 * both for HTTP 1.0 and HTTP 1.1.
74 *
75 * @param pipelineData The {@link PipelineData} object we are setting cache information for.
76 * @param expiry The number of milliseconds until the document should expire,
77 * <code>0</code> indicating immediate expiration (i.e. no caching).
78 */
79 public static void setCacheHeaders(PipelineData pipelineData, int expiry)
80 {
81 HttpServletResponse response = pipelineData.get(Turbine.class, HttpServletResponse.class);
82
83 if (0 == expiry)
84 {
85 response.setHeader("Pragma", "no-cache");
86 response.setHeader("Cache-Control", "no-cache");
87 response.setDateHeader("Expires", System.currentTimeMillis());
88 }
89 else
90 {
91 response.setDateHeader("Expires", System.currentTimeMillis() + expiry);
92 }
93 }
94
95 /**
96 * Check, if there is any not allowed {@value #CHARACTERS_NOT_ALLOWED_IN_KEY}
97 * in parameters, eg. Turbine keys like actions, screens, layouts.
98 *
99 * @param parameter or key to be checked
100 * @return True, if it contains any non allowed characters
101 */
102 public static boolean keyRequiresClean(String parameter) {
103 Matcher testMatcher = CNAIK_PATTERN.matcher(parameter);
104 return testMatcher.find();
105 }
106
107 /**
108 * Cleans parameter/key from disallowed characters defined in {@link #CHARACTERS_NOT_ALLOWED_IN_KEY}.
109 *
110 * @param parameter to be cleaned
111 * @return the cleaned parameter
112 */
113 public static String getCleanedKey(String parameter) {
114 return parameter.replaceAll(CHARACTERS_NOT_ALLOWED_IN_KEY,"");
115 }
116
117 }