/*
* JBoss, Home of Professional Open Source
* Copyright 2013, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This 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 software 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.richfaces.resource;
import static org.richfaces.resource.ResourceUtils.secondToMillis;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.text.MessageFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.faces.application.Resource;
import javax.faces.context.FacesContext;
import org.ajax4jsf.io.ByteBuffer;
import org.ajax4jsf.io.FastBufferInputStream;
import org.ajax4jsf.io.FastBufferOutputStream;
import org.richfaces.log.Logger;
import org.richfaces.log.RichfacesLogger;
/**
* @author Nick Belaevski
* @since 4.0
*/
public class CachedResourceImpl extends AbstractCacheableResource {
// [0..1]
private static final float CACHE_EXPIRATION_COEFFICIENT = 0.9f;
private static final Logger LOGGER = RichfacesLogger.RESOURCE.getLogger();
private static final int MAX_AGE_VALUE_GROUP = 2;
private static final int SMAX_AGE_GROUP = 1;
private static final Pattern MAX_AGE = Pattern.compile("^(?:(s-maxage)|max-age)=(\\d+)$", Pattern.CASE_INSENSITIVE);
private ByteBuffer content;
private String entityTag;
/**
* serves only to define server cache entry expiration time only browser cache expiration is controlled by stored HTTP
* headers value
*/
private Date expired;
private Map<String, String> headers;
private Date lastModified;
private void initializeFromHeaders() {
this.entityTag = null;
this.lastModified = null;
this.expired = null;
Date expiredFromHeader = null;
// TODO what if maxAge = 0 in header?
int maxAge = 0;
for (Entry<String, String> headerEntry : headers.entrySet()) {
String headerKey = headerEntry.getKey().toLowerCase(Locale.US);
if ("etag".equals(headerKey)) {
this.entityTag = headerEntry.getValue();
}
if ("last-modified".equals(headerKey)) {
this.lastModified = ResourceUtils.parseHttpDate(headerEntry.getValue());
}
if ("expires".equals(headerKey)) {
expiredFromHeader = ResourceUtils.parseHttpDate(headerEntry.getValue());
}
if ("cache-control".equals(headerKey)) {
String[] values = headerEntry.getValue().split(",");
for (String value : values) {
Matcher matcher = MAX_AGE.matcher(value.trim());
if (matcher.find()) {
boolean isSMaxAge = matcher.group(SMAX_AGE_GROUP) != null;
if (maxAge <= 0 || isSMaxAge) { // s-maxage overrides max-age
try {
maxAge = (int) secondToMillis(Integer.parseInt(matcher.group(MAX_AGE_VALUE_GROUP)));
} catch (NumberFormatException e) {
// TODO: handle exception
e.printStackTrace();
}
}
}
}
}
}
long currentTime = getCurrentTime();
if (maxAge > 0) {
this.expired = new Date((long) (currentTime + CACHE_EXPIRATION_COEFFICIENT * maxAge));
} else if (expiredFromHeader != null) {
// ttl = expireTime - currentTime
// CACHE_EXPIRATION_COEFFICIENT * ttl + currentTime
this.expired = new Date(
(long) (CACHE_EXPIRATION_COEFFICIENT * expiredFromHeader.getTime() + (1 - CACHE_EXPIRATION_COEFFICIENT)
* currentTime));
} else {
// TODO throw exception or modify headers?
}
}
long getCurrentTime() {
return System.currentTimeMillis();
}
private static ByteBuffer readContent(InputStream is) throws IOException {
if (is == null) {
throw new NullPointerException("Resource input stream is null");
}
FastBufferOutputStream os = new FastBufferOutputStream();
try {
ResourceUtils.copyStreamContent(is, os);
} finally {
try {
is.close();
} catch (IOException e) {
if (LOGGER.isDebugEnabled()) {
LOGGER.debug(e.getMessage(), e);
}
}
try {
os.close();
} catch (IOException e) {
if (LOGGER.isDebugEnabled()) {
LOGGER.debug(e.getMessage(), e);
}
}
}
ByteBuffer buffer = os.getFirstBuffer();
buffer.compact();
return buffer;
}
public void initialize(Resource resource) throws IOException {
setResourceName(resource.getResourceName());
setContentType(resource.getContentType());
this.headers = resource.getResponseHeaders();
initializeFromHeaders();
this.content = readContent(resource.getInputStream());
}
@Override
public InputStream getInputStream() throws IOException {
return new FastBufferInputStream(content);
}
@Override
public String getRequestPath() {
throw new UnsupportedOperationException();
}
@Override
public Map<String, String> getResponseHeaders() {
return new HashMap<String, String>(headers);
}
@Override
public URL getURL() {
throw new UnsupportedOperationException();
}
@Override
public boolean isCacheable(FacesContext context) {
return true;
}
@Override
public String getEntityTag(FacesContext context) {
return entityTag;
}
@Override
protected Date getLastModified(FacesContext context) {
return lastModified;
}
public Date getExpired(FacesContext context) {
return expired;
}
@Override
public String toString() {
return MessageFormat.format("Cached resource: {0}", getResourceName());
}
}