1 // ========================================================================
2 // Copyright (c) Webtide LLC
3 // ------------------------------------------------------------------------
4 // All rights reserved. This program and the accompanying materials
5 // are made available under the terms of the Eclipse Public License v1.0
6 // and Apache License v2.0 which accompanies this distribution.
7 // The Eclipse Public License is available at
8 // http://www.eclipse.org/legal/epl-v10.html
9 // The Apache License v2.0 is available at
10 // http://www.opensource.org/licenses/apache2.0.php
11 // You may elect to redistribute this code under either of these licenses.
12 // ========================================================================
13
14 package org.eclipse.jetty.server.handler;
15
16 import java.io.IOException;
17 import java.io.OutputStream;
18 import java.io.OutputStreamWriter;
19 import java.io.PrintWriter;
20 import java.io.UnsupportedEncodingException;
21 import java.util.HashSet;
22 import java.util.Set;
23 import java.util.StringTokenizer;
24
25 import javax.servlet.ServletException;
26 import javax.servlet.http.HttpServletRequest;
27 import javax.servlet.http.HttpServletResponse;
28
29 import org.eclipse.jetty.continuation.Continuation;
30 import org.eclipse.jetty.continuation.ContinuationListener;
31 import org.eclipse.jetty.continuation.ContinuationSupport;
32 import org.eclipse.jetty.http.HttpMethods;
33 import org.eclipse.jetty.http.gzip.GzipResponseWrapper;
34 import org.eclipse.jetty.server.Request;
35 import org.eclipse.jetty.util.log.Log;
36
37 /* ------------------------------------------------------------ */
38 /**
39 * GZIP Handler This handler will gzip the content of a response if:
40 * <ul>
41 * <li>The filter is mapped to a matching path</li>
42 * <li>The response status code is >=200 and <300
43 * <li>The content length is unknown or more than the <code>minGzipSize</code> initParameter or the minGzipSize is 0(default)</li>
44 * <li>The content-type is in the comma separated list of mimeTypes set in the <code>mimeTypes</code> initParameter or if no mimeTypes are defined the
45 * content-type is not "application/gzip"</li>
46 * <li>No content-encoding is specified by the resource</li>
47 * </ul>
48 *
49 * <p>
50 * Compressing the content can greatly improve the network bandwidth usage, but at a cost of memory and CPU cycles. If this handler is used for static content,
51 * then use of efficient direct NIO may be prevented, thus use of the gzip mechanism of the <code>org.eclipse.jetty.servlet.DefaultServlet</code> is advised instead.
52 * </p>
53 */
54 public class GzipHandler extends HandlerWrapper
55 {
56 protected Set<String> _mimeTypes;
57 protected Set<String> _excluded;
58 protected int _bufferSize = 8192;
59 protected int _minGzipSize = 256;
60
61 /* ------------------------------------------------------------ */
62 /**
63 * Instantiates a new gzip handler.
64 */
65 public GzipHandler()
66 {
67 }
68
69 /* ------------------------------------------------------------ */
70 /**
71 * Get the mime types.
72 *
73 * @return mime types to set
74 */
75 public Set<String> getMimeTypes()
76 {
77 return _mimeTypes;
78 }
79
80 /* ------------------------------------------------------------ */
81 /**
82 * Set the mime types.
83 *
84 * @param mimeTypes
85 * the mime types to set
86 */
87 public void setMimeTypes(Set<String> mimeTypes)
88 {
89 _mimeTypes = mimeTypes;
90 }
91
92 /* ------------------------------------------------------------ */
93 /**
94 * Set the mime types.
95 *
96 * @param mimeTypes
97 * the mime types to set
98 */
99 public void setMimeTypes(String mimeTypes)
100 {
101 if (mimeTypes != null)
102 {
103 _mimeTypes = new HashSet<String>();
104 StringTokenizer tok = new StringTokenizer(mimeTypes,",",false);
105 while (tok.hasMoreTokens())
106 {
107 _mimeTypes.add(tok.nextToken());
108 }
109 }
110 }
111
112 /* ------------------------------------------------------------ */
113 /**
114 * Get the excluded user agents.
115 *
116 * @return excluded user agents
117 */
118 public Set<String> getExcluded()
119 {
120 return _excluded;
121 }
122
123 /* ------------------------------------------------------------ */
124 /**
125 * Set the excluded user agents.
126 *
127 * @param excluded
128 * excluded user agents to set
129 */
130 public void setExcluded(Set<String> excluded)
131 {
132 _excluded = excluded;
133 }
134
135 /* ------------------------------------------------------------ */
136 /**
137 * Set the excluded user agents.
138 *
139 * @param excluded
140 * excluded user agents to set
141 */
142 public void setExcluded(String excluded)
143 {
144 if (excluded != null)
145 {
146 _excluded = new HashSet<String>();
147 StringTokenizer tok = new StringTokenizer(excluded,",",false);
148 while (tok.hasMoreTokens())
149 _excluded.add(tok.nextToken());
150 }
151 }
152
153 /* ------------------------------------------------------------ */
154 /**
155 * Get the buffer size.
156 *
157 * @return the buffer size
158 */
159 public int setBufferSize()
160 {
161 return _bufferSize;
162 }
163
164 /* ------------------------------------------------------------ */
165 /**
166 * Set the buffer size.
167 *
168 * @param bufferSize
169 * buffer size to set
170 */
171 public void setBufferSize(int bufferSize)
172 {
173 _bufferSize = bufferSize;
174 }
175
176 /* ------------------------------------------------------------ */
177 /**
178 * Get the minimum reponse size.
179 *
180 * @return minimum reponse size
181 */
182 public int getMinGzipSize()
183 {
184 return _minGzipSize;
185 }
186
187 /* ------------------------------------------------------------ */
188 /**
189 * Set the minimum reponse size.
190 *
191 * @param minGzipSize
192 * minimum reponse size
193 */
194 public void setMinGzipSize(int minGzipSize)
195 {
196 _minGzipSize = minGzipSize;
197 }
198
199 /* ------------------------------------------------------------ */
200 /**
201 * @see org.eclipse.jetty.server.handler.HandlerWrapper#handle(java.lang.String, org.eclipse.jetty.server.Request, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
202 */
203 @Override
204 public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
205 {
206 if (_handler!=null && isStarted())
207 {
208 String ae = request.getHeader("accept-encoding");
209 if (ae != null && ae.indexOf("gzip")>=0 && !response.containsHeader("Content-Encoding")
210 && !HttpMethods.HEAD.equalsIgnoreCase(request.getMethod()))
211 {
212 if (_excluded!=null)
213 {
214 String ua = request.getHeader("User-Agent");
215 if (_excluded.contains(ua))
216 {
217 _handler.handle(target,baseRequest, request, response);
218 return;
219 }
220 }
221
222 final GzipResponseWrapper wrappedResponse = newGzipResponseWrapper(request,response);
223
224 boolean exceptional=true;
225 try
226 {
227 _handler.handle(target, baseRequest, request, wrappedResponse);
228 exceptional=false;
229 }
230 finally
231 {
232 Continuation continuation = ContinuationSupport.getContinuation(request);
233 if (continuation.isSuspended() && continuation.isResponseWrapped())
234 {
235 continuation.addContinuationListener(new ContinuationListener()
236 {
237 public void onComplete(Continuation continuation)
238 {
239 try
240 {
241 wrappedResponse.finish();
242 }
243 catch(IOException e)
244 {
245 Log.warn(e);
246 }
247 }
248
249 public void onTimeout(Continuation continuation)
250 {}
251 });
252 }
253 else if (exceptional && !response.isCommitted())
254 {
255 wrappedResponse.resetBuffer();
256 wrappedResponse.noGzip();
257 }
258 else
259 wrappedResponse.finish();
260 }
261 }
262 else
263 {
264 _handler.handle(target,baseRequest, request, response);
265 }
266 }
267 }
268
269 /**
270 * Allows derived implementations to replace ResponseWrapper implementation.
271 *
272 * @param request the request
273 * @param response the response
274 * @return the gzip response wrapper
275 */
276 protected GzipResponseWrapper newGzipResponseWrapper(HttpServletRequest request, HttpServletResponse response)
277 {
278 return new GzipResponseWrapper(request, response)
279 {
280 {
281 setMimeTypes(GzipHandler.this._mimeTypes);
282 setBufferSize(GzipHandler.this._bufferSize);
283 setMinGzipSize(GzipHandler.this._minGzipSize);
284 }
285
286 @Override
287 protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
288 {
289 return GzipHandler.this.newWriter(out,encoding);
290 }
291 };
292 }
293
294 /**
295 * Allows derived implementations to replace PrintWriter implementation.
296 *
297 * @param out the out
298 * @param encoding the encoding
299 * @return the prints the writer
300 * @throws UnsupportedEncodingException
301 */
302 protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
303 {
304 return encoding==null?new PrintWriter(out):new PrintWriter(new OutputStreamWriter(out,encoding));
305 }
306 }