org.eclipse.jetty.servlets.gzip.GzipHandler Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.servlets.gzip;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.util.HashSet;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.GZIPOutputStream;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.http.HttpMethod;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.handler.HandlerWrapper;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
/* ------------------------------------------------------------ */
/**
* GZIP Handler This handler will gzip the content of a response if:
*
* - The filter is mapped to a matching path
* - The response status code is >=200 and <300
*
- The content length is unknown or more than the
minGzipSize initParameter or the minGzipSize is 0(default)
* - The content-type is in the comma separated list of mimeTypes set in the
mimeTypes initParameter or if no mimeTypes are defined the
* content-type is not "application/gzip"
* - No content-encoding is specified by the resource
*
*
*
* 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,
* then use of efficient direct NIO may be prevented, thus use of the gzip mechanism of the org.eclipse.jetty.servlet.DefaultServlet is advised instead.
*
*/
public class GzipHandler extends HandlerWrapper
{
private static final Logger LOG = Log.getLogger(GzipHandler.class);
final protected Set _mimeTypes=new HashSet<>();
protected boolean _excludeMimeTypes=false;
protected Set _excludedUA;
protected int _bufferSize = 8192;
protected int _minGzipSize = 256;
protected String _vary = "Accept-Encoding, User-Agent";
/* ------------------------------------------------------------ */
/**
* Instantiates a new gzip handler.
*/
public GzipHandler()
{
}
/* ------------------------------------------------------------ */
/**
* Get the mime types.
*
* @return mime types to set
*/
public Set getMimeTypes()
{
return _mimeTypes;
}
/* ------------------------------------------------------------ */
/**
* Set the mime types.
*
* @param mimeTypes
* the mime types to set
*/
public void setMimeTypes(Set mimeTypes)
{
_excludeMimeTypes=false;
_mimeTypes.clear();
_mimeTypes.addAll(mimeTypes);
}
/* ------------------------------------------------------------ */
/**
* Set the mime types.
*
* @param mimeTypes
* the mime types to set
*/
public void setMimeTypes(String mimeTypes)
{
if (mimeTypes != null)
{
_excludeMimeTypes=false;
_mimeTypes.clear();
StringTokenizer tok = new StringTokenizer(mimeTypes,",",false);
while (tok.hasMoreTokens())
{
_mimeTypes.add(tok.nextToken());
}
}
}
/* ------------------------------------------------------------ */
/**
* Set the mime types.
*/
public void setExcludeMimeTypes(boolean exclude)
{
_excludeMimeTypes=exclude;
}
/* ------------------------------------------------------------ */
/**
* Get the excluded user agents.
*
* @return excluded user agents
*/
public Set getExcluded()
{
return _excludedUA;
}
/* ------------------------------------------------------------ */
/**
* Set the excluded user agents.
*
* @param excluded
* excluded user agents to set
*/
public void setExcluded(Set excluded)
{
_excludedUA = excluded;
}
/* ------------------------------------------------------------ */
/**
* Set the excluded user agents.
*
* @param excluded
* excluded user agents to set
*/
public void setExcluded(String excluded)
{
if (excluded != null)
{
_excludedUA = new HashSet();
StringTokenizer tok = new StringTokenizer(excluded,",",false);
while (tok.hasMoreTokens())
_excludedUA.add(tok.nextToken());
}
}
/* ------------------------------------------------------------ */
/**
* @return The value of the Vary header set if a response can be compressed.
*/
public String getVary()
{
return _vary;
}
/* ------------------------------------------------------------ */
/**
* Set the value of the Vary header sent with responses that could be compressed.
*
* By default it is set to 'Accept-Encoding, User-Agent' since IE6 is excluded by
* default from the excludedAgents. If user-agents are not to be excluded, then
* this can be set to 'Accept-Encoding'. Note also that shared caches may cache
* many copies of a resource that is varied by User-Agent - one per variation of the
* User-Agent, unless the cache does some normalization of the UA string.
* @param vary The value of the Vary header set if a response can be compressed.
*/
public void setVary(String vary)
{
_vary = vary;
}
/* ------------------------------------------------------------ */
/**
* Get the buffer size.
*
* @return the buffer size
*/
public int getBufferSize()
{
return _bufferSize;
}
/* ------------------------------------------------------------ */
/**
* Set the buffer size.
*
* @param bufferSize
* buffer size to set
*/
public void setBufferSize(int bufferSize)
{
_bufferSize = bufferSize;
}
/* ------------------------------------------------------------ */
/**
* Get the minimum reponse size.
*
* @return minimum reponse size
*/
public int getMinGzipSize()
{
return _minGzipSize;
}
/* ------------------------------------------------------------ */
/**
* Set the minimum reponse size.
*
* @param minGzipSize
* minimum reponse size
*/
public void setMinGzipSize(int minGzipSize)
{
_minGzipSize = minGzipSize;
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.server.handler.HandlerWrapper#handle(java.lang.String, org.eclipse.jetty.server.Request, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
@Override
public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
{
if (_handler!=null && isStarted())
{
String ae = request.getHeader("accept-encoding");
if (ae != null && ae.indexOf("gzip")>=0 && !response.containsHeader("Content-Encoding")
&& !HttpMethod.HEAD.is(request.getMethod()))
{
if (_excludedUA!=null)
{
String ua = request.getHeader("User-Agent");
if (_excludedUA.contains(ua))
{
_handler.handle(target,baseRequest, request, response);
return;
}
}
final CompressedResponseWrapper wrappedResponse = newGzipResponseWrapper(request,response);
boolean exceptional=true;
try
{
_handler.handle(target, baseRequest, request, wrappedResponse);
exceptional=false;
}
finally
{
if (request.isAsyncStarted())
{
request.getAsyncContext().addListener(new AsyncListener()
{
@Override
public void onTimeout(AsyncEvent event) throws IOException
{
}
@Override
public void onStartAsync(AsyncEvent event) throws IOException
{
}
@Override
public void onError(AsyncEvent event) throws IOException
{
}
@Override
public void onComplete(AsyncEvent event) throws IOException
{
try
{
wrappedResponse.finish();
}
catch(IOException e)
{
LOG.warn(e);
}
}
});
}
else if (exceptional && !response.isCommitted())
{
wrappedResponse.resetBuffer();
wrappedResponse.noCompression();
}
else
wrappedResponse.finish();
}
}
else
{
_handler.handle(target,baseRequest, request, response);
}
}
}
/**
* Allows derived implementations to replace ResponseWrapper implementation.
*
* @param request the request
* @param response the response
* @return the gzip response wrapper
*/
protected CompressedResponseWrapper newGzipResponseWrapper(HttpServletRequest request, HttpServletResponse response)
{
return new CompressedResponseWrapper(request,response)
{
{
super.setMimeTypes(GzipHandler.this._mimeTypes,GzipHandler.this._excludeMimeTypes);
super.setBufferSize(GzipHandler.this._bufferSize);
super.setMinCompressSize(GzipHandler.this._minGzipSize);
}
@Override
protected AbstractCompressedStream newCompressedStream(HttpServletRequest request,HttpServletResponse response) throws IOException
{
return new AbstractCompressedStream("gzip",request,this,_vary)
{
@Override
protected DeflaterOutputStream createStream() throws IOException
{
return new GZIPOutputStream(_response.getOutputStream(),_bufferSize);
}
};
}
@Override
protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
{
return GzipHandler.this.newWriter(out,encoding);
}
};
}
/**
* Allows derived implementations to replace PrintWriter implementation.
*
* @param out the out
* @param encoding the encoding
* @return the prints the writer
* @throws UnsupportedEncodingException
*/
protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
{
return encoding==null?new PrintWriter(out):new PrintWriter(new OutputStreamWriter(out,encoding));
}
}