/**
* Copyright (c) 2000-present Liferay, Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 2.1 of the License, or (at your option)
* any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*/
package com.liferay.portal.servlet.filters.etag;
import com.liferay.portal.kernel.servlet.RestrictedByteBufferCacheServletResponse;
import com.liferay.portal.kernel.util.ParamUtil;
import com.liferay.portal.servlet.filters.BasePortalFilter;
import com.liferay.portal.util.PropsValues;
import java.nio.ByteBuffer;
import javax.servlet.FilterChain;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* @author Eduardo Lundgren
* @author Brian Wing Shun Chan
* @author Raymond Augé
* @author Shuyang Zhou
*/
public class ETagFilter extends BasePortalFilter {
public static final String SKIP_FILTER =
ETagFilter.class.getName() + "#SKIP_FILTER";
@Override
public boolean isFilterEnabled(
HttpServletRequest request, HttpServletResponse response) {
if (ParamUtil.getBoolean(request, _ETAG, true) &&
!isAlreadyFiltered(request)) {
return true;
}
else {
return false;
}
}
protected boolean isAlreadyFiltered(HttpServletRequest request) {
if (request.getAttribute(SKIP_FILTER) != null) {
return true;
}
else {
return false;
}
}
protected boolean isEligibleForETag(int status) {
if ((status >= HttpServletResponse.SC_OK) &&
(status < HttpServletResponse.SC_MULTIPLE_CHOICES)) {
return true;
}
else {
return false;
}
}
@Override
protected void processFilter(
HttpServletRequest request, HttpServletResponse response,
FilterChain filterChain)
throws Exception {
request.setAttribute(SKIP_FILTER, Boolean.TRUE);
RestrictedByteBufferCacheServletResponse
restrictedByteBufferCacheServletResponse =
new RestrictedByteBufferCacheServletResponse(
response, PropsValues.ETAG_RESPONSE_SIZE_MAX);
processFilter(
ETagFilter.class.getName(), request,
restrictedByteBufferCacheServletResponse, filterChain);
if (!restrictedByteBufferCacheServletResponse.isOverflowed()) {
ByteBuffer byteBuffer =
restrictedByteBufferCacheServletResponse.getByteBuffer();
if (!isEligibleForETag(
restrictedByteBufferCacheServletResponse.getStatus()) ||
!ETagUtil.processETag(request, response, byteBuffer)) {
restrictedByteBufferCacheServletResponse.finishResponse(false);
restrictedByteBufferCacheServletResponse.flushCache();
}
}
}
private static final String _ETAG = "etag";
}