001
014
015 package com.liferay.portal.servlet.filters.etag;
016
017 import com.liferay.portal.kernel.servlet.RestrictedByteBufferCacheServletResponse;
018 import com.liferay.portal.kernel.util.ParamUtil;
019 import com.liferay.portal.servlet.filters.BasePortalFilter;
020 import com.liferay.portal.util.PropsValues;
021
022 import java.nio.ByteBuffer;
023
024 import javax.servlet.FilterChain;
025 import javax.servlet.http.HttpServletRequest;
026 import javax.servlet.http.HttpServletResponse;
027
028
034 public class ETagFilter extends BasePortalFilter {
035
036 public static final String SKIP_FILTER =
037 ETagFilter.class.getName() + "SKIP_FILTER";
038
039 @Override
040 public boolean isFilterEnabled(
041 HttpServletRequest request, HttpServletResponse response) {
042
043 if (ParamUtil.getBoolean(request, _ETAG, true) &&
044 !isAlreadyFiltered(request)) {
045
046 return true;
047 }
048 else {
049 return false;
050 }
051 }
052
053 protected boolean isAlreadyFiltered(HttpServletRequest request) {
054 if (request.getAttribute(SKIP_FILTER) != null) {
055 return true;
056 }
057 else {
058 return false;
059 }
060 }
061
062 protected boolean isEligibleForETag(int status) {
063 if ((status >= HttpServletResponse.SC_OK) &&
064 (status < HttpServletResponse.SC_MULTIPLE_CHOICES)) {
065
066 return true;
067 }
068 else {
069 return false;
070 }
071 }
072
073 @Override
074 protected void processFilter(
075 HttpServletRequest request, HttpServletResponse response,
076 FilterChain filterChain)
077 throws Exception {
078
079 request.setAttribute(SKIP_FILTER, Boolean.TRUE);
080
081 RestrictedByteBufferCacheServletResponse
082 restrictedByteBufferCacheServletResponse =
083 new RestrictedByteBufferCacheServletResponse(
084 response, PropsValues.ETAG_RESPONSE_SIZE_MAX);
085
086 processFilter(
087 ETagFilter.class, request, restrictedByteBufferCacheServletResponse,
088 filterChain);
089
090 if (!restrictedByteBufferCacheServletResponse.isOverflowed()) {
091 ByteBuffer byteBuffer =
092 restrictedByteBufferCacheServletResponse.getByteBuffer();
093
094 if (!isEligibleForETag(
095 restrictedByteBufferCacheServletResponse.getStatus()) ||
096 !ETagUtil.processETag(request, response, byteBuffer)) {
097
098 restrictedByteBufferCacheServletResponse.finishResponse(false);
099
100 restrictedByteBufferCacheServletResponse.flushCache();
101 }
102 }
103 }
104
105 private static final String _ETAG = "etag";
106
107 }