1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
|
/*
* ====================================================================
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package ch.boye.httpclientandroidlib.impl.client.cache;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import ch.boye.httpclientandroidlib.Consts;
import ch.boye.httpclientandroidlib.Header;
import ch.boye.httpclientandroidlib.HeaderElement;
import ch.boye.httpclientandroidlib.HttpHost;
import ch.boye.httpclientandroidlib.HttpRequest;
import ch.boye.httpclientandroidlib.annotation.Immutable;
import ch.boye.httpclientandroidlib.client.cache.HeaderConstants;
import ch.boye.httpclientandroidlib.client.cache.HttpCacheEntry;
import ch.boye.httpclientandroidlib.client.utils.URIUtils;
/**
* @since 4.1
*/
@Immutable
class CacheKeyGenerator {
private static final URI BASE_URI = URI.create("http://example.com/");
/**
* For a given {@link HttpHost} and {@link HttpRequest} get a URI from the
* pair that I can use as an identifier KEY into my HttpCache
*
* @param host The host for this request
* @param req the {@link HttpRequest}
* @return String the extracted URI
*/
public String getURI(final HttpHost host, final HttpRequest req) {
if (isRelativeRequest(req)) {
return canonicalizeUri(String.format("%s%s", host.toString(), req.getRequestLine().getUri()));
}
return canonicalizeUri(req.getRequestLine().getUri());
}
public String canonicalizeUri(final String uri) {
try {
final URI normalized = URIUtils.resolve(BASE_URI, uri);
final URL u = new URL(normalized.toASCIIString());
final String protocol = u.getProtocol();
final String hostname = u.getHost();
final int port = canonicalizePort(u.getPort(), protocol);
final String path = u.getPath();
final String query = u.getQuery();
final String file = (query != null) ? (path + "?" + query) : path;
final URL out = new URL(protocol, hostname, port, file);
return out.toString();
} catch (final IllegalArgumentException e) {
return uri;
} catch (final MalformedURLException e) {
return uri;
}
}
private int canonicalizePort(final int port, final String protocol) {
if (port == -1 && "http".equalsIgnoreCase(protocol)) {
return 80;
} else if (port == -1 && "https".equalsIgnoreCase(protocol)) {
return 443;
}
return port;
}
private boolean isRelativeRequest(final HttpRequest req) {
final String requestUri = req.getRequestLine().getUri();
return ("*".equals(requestUri) || requestUri.startsWith("/"));
}
protected String getFullHeaderValue(final Header[] headers) {
if (headers == null) {
return "";
}
final StringBuilder buf = new StringBuilder("");
boolean first = true;
for (final Header hdr : headers) {
if (!first) {
buf.append(", ");
}
buf.append(hdr.getValue().trim());
first = false;
}
return buf.toString();
}
/**
* For a given {@link HttpHost} and {@link HttpRequest} if the request has a
* VARY header - I need to get an additional URI from the pair of host and
* request so that I can also store the variant into my HttpCache.
*
* @param host The host for this request
* @param req the {@link HttpRequest}
* @param entry the parent entry used to track the variants
* @return String the extracted variant URI
*/
public String getVariantURI(final HttpHost host, final HttpRequest req, final HttpCacheEntry entry) {
if (!entry.hasVariants()) {
return getURI(host, req);
}
return getVariantKey(req, entry) + getURI(host, req);
}
/**
* Compute a "variant key" from the headers of a given request that are
* covered by the Vary header of a given cache entry. Any request whose
* varying headers match those of this request should have the same
* variant key.
* @param req originating request
* @param entry cache entry in question that has variants
* @return a <code>String</code> variant key
*/
public String getVariantKey(final HttpRequest req, final HttpCacheEntry entry) {
final List<String> variantHeaderNames = new ArrayList<String>();
for (final Header varyHdr : entry.getHeaders(HeaderConstants.VARY)) {
for (final HeaderElement elt : varyHdr.getElements()) {
variantHeaderNames.add(elt.getName());
}
}
Collections.sort(variantHeaderNames);
StringBuilder buf;
try {
buf = new StringBuilder("{");
boolean first = true;
for (final String headerName : variantHeaderNames) {
if (!first) {
buf.append("&");
}
buf.append(URLEncoder.encode(headerName, Consts.UTF_8.name()));
buf.append("=");
buf.append(URLEncoder.encode(getFullHeaderValue(req.getHeaders(headerName)),
Consts.UTF_8.name()));
first = false;
}
buf.append("}");
} catch (final UnsupportedEncodingException uee) {
throw new RuntimeException("couldn't encode to UTF-8", uee);
}
return buf.toString();
}
}
|
