package org.helios.netty.ajax.handlergroups.fileserver;
import static org.jboss.netty.handler.codec.http.HttpHeaders.isKeepAlive;
import static org.jboss.netty.handler.codec.http.HttpHeaders.setContentLength;
import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;
import static org.jboss.netty.handler.codec.http.HttpMethod.GET;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.FORBIDDEN;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.INTERNAL_SERVER_ERROR;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.METHOD_NOT_ALLOWED;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.NOT_FOUND;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.OK;
import static org.jboss.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Locale;
import java.util.Map;
import java.util.TimeZone;
import java.util.concurrent.ConcurrentHashMap;
import javax.activation.MimetypesFileTypeMap;
import org.apache.log4j.Logger;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelFutureProgressListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.DefaultFileRegion;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.FileRegion;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
import org.jboss.netty.handler.codec.frame.TooLongFrameException;
import org.jboss.netty.handler.codec.http.DefaultHttpResponse;
import org.jboss.netty.handler.codec.http.HttpHeaders;
import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.handler.codec.http.HttpResponse;
import org.jboss.netty.handler.codec.http.HttpResponseStatus;
import org.jboss.netty.handler.ssl.SslHandler;
import org.jboss.netty.handler.stream.ChunkedFile;
import org.jboss.netty.util.CharsetUtil;
/**
* Modified for Netty Ajax Server example project
* to read content from a specified directory.
*
* A simple handler that serves incoming HTTP requests to send their respective
* HTTP responses. It also implements {@code 'If-Modified-Since'} header to
* take advantage of browser cache, as described in
* <a href="http://tools.ietf.org/html/rfc2616#section-14.25">RFC 2616</a>.
*
* <h3>How Browser Caching Works</h3>
*
* Web browser caching works with HTTP headers as illustrated by the following
* sample:
* <ol>
* <li>Request #1 returns the content of <code>/file1.txt</code>.</li>
* <li>Contents of <code>/file1.txt</code> is cached by the browser.</li>
* <li>Request #2 for <code>/file1.txt</code> does return the contents of the
* file again. Rather, a 304 Not Modified is returned. This tells the
* browser to use the contents stored in its cache.</li>
* <li>The server knows the file has not been modified because the
* <code>If-Modified-Since</code> date is the same as the file's last
* modified date.</li>
* </ol>
*
* <pre>
* Request #1 Headers
* ===================
* GET /file1.txt HTTP/1.1
*
* Response #1 Headers
* ===================
* HTTP/1.1 200 OK
* Date: Tue, 01 Mar 2011 22:44:26 GMT
* Last-Modified: Wed, 30 Jun 2010 21:36:48 GMT
* Expires: Tue, 01 Mar 2012 22:44:26 GMT
* Cache-Control: private, max-age=31536000
*
* Request #2 Headers
* ===================
* GET /file1.txt HTTP/1.1
* If-Modified-Since: Wed, 30 Jun 2010 21:36:48 GMT
*
* Response #2 Headers
* ===================
* HTTP/1.1 304 Not Modified
* Date: Tue, 01 Mar 2011 22:44:28 GMT
*
* </pre>
*/
public class HttpStaticFileServerHandler extends SimpleChannelUpstreamHandler {
public static final String HTTP_DATE_FORMAT = "EEE, dd MMM yyyy HH:mm:ss zzz";
public static final String HTTP_DATE_GMT_TIMEZONE = "GMT";
public static final int HTTP_CACHE_SECONDS = 60;
protected static final Logger LOG = Logger.getLogger(HttpStaticFileServerHandler.class);
/** Indicates if content will be loaded from a jar as resources, or from the file system */
protected final boolean inJar;
/** This class's class loader */
protected final ClassLoader classLoader = getClass().getClassLoader();
/** The content root representation */
public static String contentRoot;
/** A cache of loaded resources shared amongst file server handler instances */
protected static final Map<String, HttpResponse> contentCache = new ConcurrentHashMap<String, HttpResponse>(1024);
/** The Mime type assigner */
protected static final MimetypesFileTypeMap mimeTypesMap = new MimetypesFileTypeMap();
static {
mimeTypesMap.addMimeTypes("application/js");
}
/**
* Creates a new HttpStaticFileServerHandler
*/
public HttpStaticFileServerHandler() {
inJar = getClass().getProtectionDomain().getCodeSource().getLocation().toString().toLowerCase().endsWith(".jar");
LOG.info("HTTP File Server Resource Mode:" + inJar);
}
/**
* {@inheritDoc}
* @see org.jboss.netty.channel.SimpleChannelUpstreamHandler#messageReceived(org.jboss.netty.channel.ChannelHandlerContext, org.jboss.netty.channel.MessageEvent)
*/
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
HttpRequest request = (HttpRequest) e.getMessage();
if (request.getMethod() != GET) {
sendError(ctx, METHOD_NOT_ALLOWED);
return;
}
String path = request.getUri();
if (path == null) {
sendError(ctx, FORBIDDEN);
return;
}
if(path.equals("")) {
path = "index.html";
}
if(path.equals("/")) {
path = "index.html";
}
ChannelFuture writeFuture = null;
if(inJar) {
writeFuture = writeResponseFromResource(ctx, e, request, path);
} else {
writeFuture = writeResponseFromFile(ctx, e, request, path);
}
// Decide whether to close the connection or not.
if (writeFuture!=null && !isKeepAlive(request)) {
// Close the connection when the whole content is written out.
writeFuture.addListener(ChannelFutureListener.CLOSE);
}
}
/**
* Writes the content request response from the jar
* @param ctx
* @param e
* @param request
* @param path
* @return
* @throws ParseException
* @throws IOException
*/
private ChannelFuture writeResponseFromResource(ChannelHandlerContext ctx,
MessageEvent e, HttpRequest request, String path)
throws ParseException, IOException {
InputStream is = null;
ByteArrayOutputStream baos = null;
try {
StringBuilder b = new StringBuilder(path);
if(b.charAt(0)=='/') {
b.deleteCharAt(0);
}
b.insert(0, "www/");
String resourcePath = b.toString();
LOG.info("HTTP File Server Request [" + resourcePath + "]");
HttpResponse response = contentCache.get(resourcePath);
if(response==null) {
synchronized(contentCache) {
response = contentCache.get(resourcePath);
if(response==null) {
is = classLoader.getResourceAsStream(b.toString());
if(is.available()==0) {
sendError(ctx, NOT_FOUND);
return null;
}
baos = new ByteArrayOutputStream(is.available());
int bt = -1;
while((bt=is.read())!=-1) {
baos.write(bt);
}
byte[] content = baos.toByteArray();
response = new DefaultHttpResponse(HTTP_1_1, OK);
setContentLength(response, content.length);
setContentTypeHeader(response, resourcePath);
setDateAndCacheHeaders(response, resourcePath);
response.setContent(ChannelBuffers.wrappedBuffer(content));
contentCache.put(resourcePath, response);
}
}
}
Channel ch = e.getChannel();
// Write the initial line and the header.
return ch.write(response);
} finally {
if(is!=null) try { is.close(); } catch (Exception e2) {}
if(baos!=null) try { baos.close(); } catch (Exception e3) {}
}
}
/**
* Writes the content request response from the file system
* @param ctx
* @param e
* @param request
* @param path
* @return
* @throws ParseException
* @throws IOException
*/
private ChannelFuture writeResponseFromFile(ChannelHandlerContext ctx,
MessageEvent e, HttpRequest request, String path)
throws ParseException, IOException {
File file = new File(contentRoot + File.separator + path);
if (file.isHidden() || !file.exists()) {
sendError(ctx, NOT_FOUND);
return null;
}
if (!file.isFile()) {
sendError(ctx, FORBIDDEN);
return null;
}
// Cache Validation
String ifModifiedSince = request.getHeader(HttpHeaders.Names.IF_MODIFIED_SINCE);
if (ifModifiedSince != null && !ifModifiedSince.equals("")) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
Date ifModifiedSinceDate = dateFormatter.parse(ifModifiedSince);
// Only compare up to the second because the datetime format we send to the client does not have milliseconds
long ifModifiedSinceDateSeconds = ifModifiedSinceDate.getTime() / 1000;
long fileLastModifiedSeconds = file.lastModified() / 1000;
if (ifModifiedSinceDateSeconds == fileLastModifiedSeconds) {
sendNotModified(ctx);
return null;
}
}
RandomAccessFile raf;
try {
raf = new RandomAccessFile(file, "r");
} catch (FileNotFoundException fnfe) {
sendError(ctx, NOT_FOUND);
return null;
}
long fileLength = raf.length();
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);
setContentLength(response, fileLength);
setContentTypeHeader(response, file.getAbsolutePath());
setDateAndCacheHeaders(response, file);
Channel ch = e.getChannel();
// Write the initial line and the header.
ch.write(response);
// Write the content.
ChannelFuture writeFuture;
if (ch.getPipeline().get(SslHandler.class) != null) {
// Cannot use zero-copy with HTTPS.
writeFuture = ch.write(new ChunkedFile(raf, 0, fileLength, 8192));
} else {
// No encryption - use zero-copy.
final FileRegion region =
new DefaultFileRegion(raf.getChannel(), 0, fileLength);
writeFuture = ch.write(region);
final String finalPath = path;
writeFuture.addListener(new ChannelFutureProgressListener() {
public void operationComplete(ChannelFuture future) {
region.releaseExternalResources();
}
public void operationProgressed(
ChannelFuture future, long amount, long current, long total) {
System.out.printf("%s: %d / %d (+%d)%n", finalPath, current, total, amount);
}
});
}
return writeFuture;
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
throws Exception {
Channel ch = e.getChannel();
Throwable cause = e.getCause();
if (cause instanceof TooLongFrameException) {
sendError(ctx, BAD_REQUEST);
return;
}
cause.printStackTrace();
if (ch.isConnected()) {
sendError(ctx, INTERNAL_SERVER_ERROR);
}
}
private void sendError(ChannelHandlerContext ctx, HttpResponseStatus status) {
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, status);
response.setHeader(CONTENT_TYPE, "text/plain; charset=UTF-8");
response.setContent(ChannelBuffers.copiedBuffer(
"Failure: " + status.toString() + "\r\n",
CharsetUtil.UTF_8));
// Close the connection as soon as the error message is sent.
ctx.getChannel().write(response).addListener(ChannelFutureListener.CLOSE);
}
/**
* When file timestamp is the same as what the browser is sending up, send a "304 Not Modified"
*
* @param ctx
* Context
*/
private void sendNotModified(ChannelHandlerContext ctx) {
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, HttpResponseStatus.NOT_MODIFIED);
setDateHeader(response);
// Close the connection as soon as the error message is sent.
ctx.getChannel().write(response).addListener(ChannelFutureListener.CLOSE);
}
/**
* Sets the Date header for the HTTP response
*
* @param response
* HTTP response
*/
private void setDateHeader(HttpResponse response) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
dateFormatter.setTimeZone(TimeZone.getTimeZone(HTTP_DATE_GMT_TIMEZONE));
Calendar time = new GregorianCalendar();
response.setHeader(HttpHeaders.Names.DATE, dateFormatter.format(time.getTime()));
}
/**
* Sets the Date and Cache headers for the HTTP Response
*
* @param response
* HTTP response
* @param fileToCache
* file to extract content type
*/
private void setDateAndCacheHeaders(HttpResponse response, File fileToCache) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
dateFormatter.setTimeZone(TimeZone.getTimeZone(HTTP_DATE_GMT_TIMEZONE));
// Date header
Calendar time = new GregorianCalendar();
response.setHeader(HttpHeaders.Names.DATE, dateFormatter.format(time.getTime()));
// Add cache headers
time.add(Calendar.SECOND, HTTP_CACHE_SECONDS);
response.setHeader(HttpHeaders.Names.EXPIRES, dateFormatter.format(time.getTime()));
response.setHeader(HttpHeaders.Names.CACHE_CONTROL, "private, max-age=" + HTTP_CACHE_SECONDS);
response.setHeader(HttpHeaders.Names.LAST_MODIFIED, dateFormatter.format(new Date(fileToCache.lastModified())));
}
/**
* @param response
* @param resourceName
*/
private void setDateAndCacheHeaders(HttpResponse response, String resourceName) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
dateFormatter.setTimeZone(TimeZone.getTimeZone(HTTP_DATE_GMT_TIMEZONE));
// Date header
Calendar time = new GregorianCalendar();
response.setHeader(HttpHeaders.Names.DATE, dateFormatter.format(time.getTime()));
// Add cache headers
time.add(Calendar.SECOND, HTTP_CACHE_SECONDS);
response.setHeader(HttpHeaders.Names.EXPIRES, dateFormatter.format(time.getTime()));
response.setHeader(HttpHeaders.Names.CACHE_CONTROL, "private, max-age=" + HTTP_CACHE_SECONDS);
response.setHeader(HttpHeaders.Names.LAST_MODIFIED, dateFormatter.format(new Date()));
}
/**
* Sets the content type header for the HTTP Response
*
* @param response
* HTTP response
* @param file
* file to extract content type
*/
private void setContentTypeHeader(HttpResponse response, String resourceName) {
response.setHeader(HttpHeaders.Names.CONTENT_TYPE, mimeTypesMap.getContentType(resourceName));
}
}