package io.undertow.server.handlers.encoding;
import io.undertow.UndertowLogger;
import io.undertow.predicate.Predicate;
import io.undertow.server.HttpServerExchange;
import io.undertow.server.handlers.resource.CachingResourceManager;
import io.undertow.server.handlers.resource.Resource;
import io.undertow.util.ImmediateConduitFactory;
import org.xnio.FileAccess;
import org.xnio.IoUtils;
import org.xnio.XnioIoThread;
import org.xnio.XnioWorker;
import org.xnio.channels.StreamSourceChannel;
import org.xnio.conduits.ConduitStreamSinkChannel;
import org.xnio.conduits.Conduits;
import org.xnio.conduits.StreamSinkConduit;
import org.xnio.conduits.WriteReadyHandler;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;
/**
* Class that provides a way of serving pre-encoded resources.
*
* @author Stuart Douglas
*/
public class ContentEncodedResourceManager {
private final File encodedResourcesRoot;
private final CachingResourceManager encoded;
private final ContentEncodingRepository contentEncodingRepository;
private final int minResourceSize;
private final int maxResourceSize;
private final Predicate encodingAllowed;
private final ConcurrentMap<LockKey, Object> fileLocks = new ConcurrentHashMap<LockKey, Object>();
public ContentEncodedResourceManager(File encodedResourcesRoot, CachingResourceManager encodedResourceManager, ContentEncodingRepository contentEncodingRepository, int minResourceSize, int maxResourceSize, Predicate encodingAllowed) {
this.encodedResourcesRoot = encodedResourcesRoot;
this.encoded = encodedResourceManager;
this.contentEncodingRepository = contentEncodingRepository;
this.minResourceSize = minResourceSize;
this.maxResourceSize = maxResourceSize;
this.encodingAllowed = encodingAllowed;
}
/**
* Gets a pre-encoded resource.
* <p/>
* TODO: blocking / non-blocking semantics
*
* @param resource
* @param exchange
* @return
* @throws IOException
*/
public ContentEncodedResource getResource(final Resource resource, final HttpServerExchange exchange) throws IOException {
final String path = resource.getPath();
File file = resource.getFile();
if (file == null) {
return null;
}
if (minResourceSize > 0 && resource.getContentLength() < minResourceSize ||
maxResourceSize > 0 && resource.getContentLength() > maxResourceSize ||
!(encodingAllowed == null || encodingAllowed.resolve(exchange))) {
return null;
}
AllowedContentEncodings encodings = contentEncodingRepository.getContentEncodings(exchange);
if (encodings == null || encodings.isNoEncodingsAllowed()) {
return null;
}
EncodingMapping encoding = encodings.getEncoding();
if (encoding == null || encoding.getName().equals(ContentEncodingRepository.IDENTITY)) {
return null;
}
String newPath = path + ".undertow.encoding." + encoding.getName();
Resource preCompressed = encoded.getResource(newPath);
if (preCompressed != null) {
return new ContentEncodedResource(preCompressed, encoding.getName());
}
final LockKey key = new LockKey(path, encoding.getName());
if (fileLocks.putIfAbsent(key, this) != null) {
//another thread is already compressing
//we don't do anything fancy here, just return and serve non-compressed content
return null;
}
FileChannel targetFileChannel = null;
FileChannel sourceFileChannel = null;
try {
//double check, the compressing thread could have finished just before we acquired the lock
preCompressed = encoded.getResource(newPath);
if (preCompressed != null) {
return new ContentEncodedResource(preCompressed, encoding.getName());
}
final File finalTarget = new File(encodedResourcesRoot, newPath);
final File tempTarget = new File(encodedResourcesRoot, newPath);
//horrible hack to work around XNIO issue
FileOutputStream tmp = new FileOutputStream(tempTarget);
try {
tmp.close();
} finally {
IoUtils.safeClose(tmp);
}
targetFileChannel = exchange.getConnection().getWorker().getXnio().openFile(tempTarget, FileAccess.READ_WRITE);
sourceFileChannel = exchange.getConnection().getWorker().getXnio().openFile(file, FileAccess.READ_ONLY);
StreamSinkConduit conduit = encoding.getEncoding().getResponseWrapper().wrap(new ImmediateConduitFactory<StreamSinkConduit>(new FileConduitTarget(targetFileChannel, exchange)), exchange);
final ConduitStreamSinkChannel targetChannel = new ConduitStreamSinkChannel(null, conduit);
long transferred = sourceFileChannel.transferTo(0, resource.getContentLength(), targetChannel);
targetChannel.shutdownWrites();
org.xnio.channels.Channels.flushBlocking(targetChannel);
if (transferred != resource.getContentLength()) {
UndertowLogger.REQUEST_LOGGER.error("Failed to write pre-cached file");
}
tempTarget.renameTo(finalTarget);
encoded.invalidate(newPath);
final Resource encodedResource = encoded.getResource(newPath);
return new ContentEncodedResource(encodedResource, encoding.getName());
} finally {
IoUtils.safeClose(targetFileChannel);
IoUtils.safeClose(sourceFileChannel);
fileLocks.remove(key);
}
}
private final class LockKey {
private final String path;
private final String encoding;
private LockKey(String path, String encoding) {
this.path = path;
this.encoding = encoding;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
LockKey lockKey = (LockKey) o;
if (encoding != null ? !encoding.equals(lockKey.encoding) : lockKey.encoding != null) return false;
if (path != null ? !path.equals(lockKey.path) : lockKey.path != null) return false;
return true;
}
@Override
public int hashCode() {
int result = path != null ? path.hashCode() : 0;
result = 31 * result + (encoding != null ? encoding.hashCode() : 0);
return result;
}
}
private static final class FileConduitTarget implements StreamSinkConduit {
private final FileChannel fileChannel;
private final HttpServerExchange exchange;
private WriteReadyHandler writeReadyHandler;
private boolean writesResumed = false;
private FileConduitTarget(FileChannel fileChannel, HttpServerExchange exchange) {
this.fileChannel = fileChannel;
this.exchange = exchange;
}
@Override
public long transferFrom(FileChannel fileChannel, long l, long l2) throws IOException {
return this.fileChannel.transferFrom(fileChannel, l, l2);
}
@Override
public long transferFrom(StreamSourceChannel streamSourceChannel, long l, ByteBuffer byteBuffer) throws IOException {
return IoUtils.transfer(streamSourceChannel, l, byteBuffer, fileChannel);
}
@Override
public int write(ByteBuffer byteBuffer) throws IOException {
return fileChannel.write(byteBuffer);
}
@Override
public long write(ByteBuffer[] byteBuffers, int i, int i2) throws IOException {
return fileChannel.write(byteBuffers, i, i2);
}
@Override
public int writeFinal(ByteBuffer src) throws IOException {
return Conduits.writeFinalBasic(this, src);
}
@Override
public long writeFinal(ByteBuffer[] srcs, int offset, int length) throws IOException {
return Conduits.writeFinalBasic(this, srcs, offset, length);
}
@Override
public void terminateWrites() throws IOException {
fileChannel.close();
}
@Override
public boolean isWriteShutdown() {
return !fileChannel.isOpen();
}
@Override
public void resumeWrites() {
wakeupWrites();
}
@Override
public void suspendWrites() {
writesResumed = false;
}
@Override
public void wakeupWrites() {
if (writeReadyHandler != null) {
writesResumed = true;
while (writesResumed && writeReadyHandler != null) {
writeReadyHandler.writeReady();
}
}
}
@Override
public boolean isWriteResumed() {
return writesResumed;
}
@Override
public void awaitWritable() throws IOException {
}
@Override
public void awaitWritable(long l, TimeUnit timeUnit) throws IOException {
}
@Override
public XnioIoThread getWriteThread() {
return exchange.getIoThread();
}
@Override
public void setWriteReadyHandler(WriteReadyHandler writeReadyHandler) {
this.writeReadyHandler = writeReadyHandler;
}
@Override
public void truncateWrites() throws IOException {
fileChannel.close();
}
@Override
public boolean flush() throws IOException {
return true;
}
@Override
public XnioWorker getWorker() {
return exchange.getConnection().getWorker();
}
}
}