io.undertow.server.handlers.resource.CachedResource Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* JBoss, Home of Professional Open Source.
* Copyright 2014 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.undertow.server.handlers.resource;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.file.Path;
import java.util.Date;
import java.util.List;
import io.undertow.UndertowLogger;
import io.undertow.io.IoCallback;
import io.undertow.io.Sender;
import io.undertow.server.HttpServerExchange;
import io.undertow.server.handlers.cache.DirectBufferCache;
import io.undertow.server.handlers.cache.LimitedBufferSlicePool;
import io.undertow.server.handlers.cache.ResponseCachingSender;
import io.undertow.util.DateUtils;
import io.undertow.util.ETag;
import io.undertow.util.MimeMappings;
/**
* @author Stuart Douglas
*/
public class CachedResource implements Resource, RangeAwareResource {
private final CacheKey cacheKey;
private final CachingResourceManager cachingResourceManager;
private final Resource underlyingResource;
private final boolean directory;
private final Date lastModifiedDate;
private final String lastModifiedDateString;
private final ETag eTag;
private final String name;
private volatile long nextMaxAgeCheck;
public CachedResource(final CachingResourceManager cachingResourceManager, final Resource underlyingResource, final String path) {
this.cachingResourceManager = cachingResourceManager;
this.underlyingResource = underlyingResource;
this.directory = underlyingResource.isDirectory();
this.lastModifiedDate = underlyingResource.getLastModified();
if (lastModifiedDate != null) {
this.lastModifiedDateString = DateUtils.toDateString(lastModifiedDate);
} else {
this.lastModifiedDateString = null;
}
this.eTag = underlyingResource.getETag();
this.name = underlyingResource.getName();
this.cacheKey = new CacheKey(cachingResourceManager, underlyingResource.getCacheKey());
if (cachingResourceManager.getMaxAge() > 0) {
nextMaxAgeCheck = System.currentTimeMillis() + cachingResourceManager.getMaxAge();
} else {
nextMaxAgeCheck = -1;
}
}
@Override
public String getPath() {
return underlyingResource.getPath();
}
@Override
public Date getLastModified() {
return lastModifiedDate;
}
@Override
public String getLastModifiedString() {
return lastModifiedDateString;
}
@Override
public ETag getETag() {
return eTag;
}
@Override
public String getName() {
return name;
}
@Override
public boolean isDirectory() {
return directory;
}
@Override
public List list() {
return underlyingResource.list();
}
@Override
public String getContentType(final MimeMappings mimeMappings) {
return underlyingResource.getContentType(mimeMappings);
}
public void invalidate() {
final DirectBufferCache dataCache = cachingResourceManager.getDataCache();
if(dataCache != null) {
dataCache.remove(cacheKey);
}
}
public boolean checkStillValid() {
if (nextMaxAgeCheck > 0) {
long time = System.currentTimeMillis();
if (time > nextMaxAgeCheck) {
nextMaxAgeCheck = time + cachingResourceManager.getMaxAge();
if (!underlyingResource.getLastModified().equals(lastModifiedDate)) {
return false;
}
}
}
return true;
}
@Override
public void serve(final Sender sender, final HttpServerExchange exchange, final IoCallback completionCallback) {
final DirectBufferCache dataCache = cachingResourceManager.getDataCache();
if(dataCache == null) {
underlyingResource.serve(sender, exchange, completionCallback);
return;
}
final DirectBufferCache.CacheEntry existing = dataCache.get(cacheKey);
final Long length = getContentLength();
//if it is not eligible to be served from the cache
if (length == null || length > cachingResourceManager.getMaxFileSize()) {
underlyingResource.serve(sender, exchange, completionCallback);
return;
}
//it is not cached yet, install a wrapper to grab the data
if (existing == null || !existing.enabled() || !existing.reference()) {
Sender newSender = sender;
final DirectBufferCache.CacheEntry entry;
if (existing == null) {
entry = dataCache.add(cacheKey, length.intValue(), cachingResourceManager.getMaxAge());
} else {
entry = existing;
}
if (entry != null && entry.buffers().length != 0 && entry.claimEnable()) {
if (entry.reference()) {
newSender = new ResponseCachingSender(sender, entry, length);
} else {
entry.disable();
}
}
underlyingResource.serve(newSender, exchange, completionCallback);
} else {
UndertowLogger.REQUEST_LOGGER.tracef("Serving resource %s from the buffer cache to %s", name, exchange);
//serve straight from the cache
ByteBuffer[] buffers;
boolean ok = false;
try {
LimitedBufferSlicePool.PooledByteBuffer[] pooled = existing.buffers();
buffers = new ByteBuffer[pooled.length];
for (int i = 0; i < buffers.length; i++) {
// Keep position from mutating
buffers[i] = pooled[i].getBuffer().duplicate();
}
ok = true;
} finally {
if (!ok) {
existing.dereference();
}
}
sender.send(buffers, new DereferenceCallback(existing, completionCallback));
}
}
@Override
public Long getContentLength() {
//we always use the underlying size unless the data is cached in the buffer cache
//to prevent a mis-match between size on disk and cached size
final DirectBufferCache dataCache = cachingResourceManager.getDataCache();
if(dataCache == null) {
return underlyingResource.getContentLength();
}
final DirectBufferCache.CacheEntry existing = dataCache.get(cacheKey);
if(existing == null || !existing.enabled()) {
return underlyingResource.getContentLength();
}
//we only return the
return (long)existing.size();
}
@Override
public String getCacheKey() {
return cacheKey.cacheKey;
}
@Override
public File getFile() {
return underlyingResource.getFile();
}
@Override
public Path getFilePath() {
return underlyingResource.getFilePath();
}
@Override
public File getResourceManagerRoot() {
return underlyingResource.getResourceManagerRoot();
}
@Override
public Path getResourceManagerRootPath() {
return underlyingResource.getResourceManagerRootPath();
}
@Override
public URL getUrl() {
return underlyingResource.getUrl();
}
@Override
public void serveRange(Sender sender, HttpServerExchange exchange, long start, long end, IoCallback completionCallback) {
final DirectBufferCache dataCache = cachingResourceManager.getDataCache();
if(dataCache == null) {
((RangeAwareResource)underlyingResource).serveRange(sender, exchange, start, end, completionCallback);
return;
}
final DirectBufferCache.CacheEntry existing = dataCache.get(cacheKey);
final Long length = getContentLength();
//if it is not eligible to be served from the cache
if (length == null || length > cachingResourceManager.getMaxFileSize()) {
((RangeAwareResource)underlyingResource).serveRange(sender, exchange, start, end, completionCallback);
return;
}
//it is not cached yet, just serve it directly
if (existing == null || !existing.enabled() || !existing.reference()) {
//it is not cached yet, we can't use a range request to establish the cached item
//so we just serve it
((RangeAwareResource)underlyingResource).serveRange(sender, exchange, start, end, completionCallback);
} else {
//serve straight from the cache
ByteBuffer[] buffers;
boolean ok = false;
try {
LimitedBufferSlicePool.PooledByteBuffer[] pooled = existing.buffers();
buffers = new ByteBuffer[pooled.length];
for (int i = 0; i < buffers.length; i++) {
// Keep position from mutating
buffers[i] = pooled[i].getBuffer().duplicate();
}
ok = true;
} finally {
if (!ok) {
existing.dereference();
}
}
long endTarget = end + 1; //as it is inclusive
long startDec = start;
long endCount = 0;
//handle the start of the range
for (ByteBuffer b : buffers) {
if (endCount == endTarget) {
b.limit(b.position());
continue;
} else if (endCount + b.remaining() < endTarget) {
endCount += b.remaining();
} else {
b.limit((int) (b.position() + (endTarget - endCount)));
endCount = endTarget;
}
if (b.remaining() >= startDec) {
b.position((int) (b.position() + startDec));
startDec = 0;
} else {
startDec -= b.remaining();
b.position(b.limit());
}
}
sender.send(buffers, new DereferenceCallback(existing, completionCallback));
}
}
@Override
public boolean isRangeSupported() {
//we can only handle range requests if the underlying resource supports it
//even if we have the resource in the cache it may disappear before we try and serve it
return underlyingResource instanceof RangeAwareResource && ((RangeAwareResource) underlyingResource).isRangeSupported();
}
private static class DereferenceCallback implements IoCallback {
private final DirectBufferCache.CacheEntry entry;
private final IoCallback callback;
DereferenceCallback(DirectBufferCache.CacheEntry entry, final IoCallback callback) {
this.entry = entry;
this.callback = callback;
}
@Override
public void onComplete(final HttpServerExchange exchange, final Sender sender) {
try {
entry.dereference();
} finally {
callback.onComplete(exchange, sender);
}
}
@Override
public void onException(final HttpServerExchange exchange, final Sender sender, final IOException exception) {
UndertowLogger.REQUEST_IO_LOGGER.ioException(exception);
try {
entry.dereference();
} finally {
callback.onException(exchange, sender, exception);
}
}
}
static final class CacheKey {
final CachingResourceManager manager;
final String cacheKey;
CacheKey(CachingResourceManager manager, String cacheKey) {
this.manager = manager;
this.cacheKey = cacheKey;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
CacheKey cacheKey1 = (CacheKey) o;
if (cacheKey != null ? !cacheKey.equals(cacheKey1.cacheKey) : cacheKey1.cacheKey != null) return false;
if (manager != null ? !manager.equals(cacheKey1.manager) : cacheKey1.manager != null) return false;
return true;
}
@Override
public int hashCode() {
int result = manager != null ? manager.hashCode() : 0;
result = 31 * result + (cacheKey != null ? cacheKey.hashCode() : 0);
return result;
}
}
}