Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you 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 com.just.server.http.file; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.*; import io.netty.handler.codec.http.*; import io.netty.handler.ssl.SslHandler; import io.netty.handler.stream.ChunkedFile; import io.netty.util.CharsetUtil; import io.netty.util.internal.SystemPropertyUtil; import javax.activation.MimetypesFileTypeMap; import java.io.File; import java.io.FileNotFoundException; import java.io.RandomAccessFile; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.text.SimpleDateFormat; import java.util.*; import java.util.regex.Pattern; import static io.netty.handler.codec.http.HttpMethod.GET; import static io.netty.handler.codec.http.HttpResponseStatus.*; import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; public class HttpStaticFileServerHandler extends SimpleChannelInboundHandler<FullHttpRequest> { 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; @Override public void channelRead0(ChannelHandlerContext ctx, FullHttpRequest request) throws Exception { if (!request.decoderResult().isSuccess()) { sendError(ctx, BAD_REQUEST); return; } if (request.method() != GET) { sendError(ctx, METHOD_NOT_ALLOWED); return; } final String uri = request.uri(); final String path = sanitizeUri(uri); if (path == null) { sendError(ctx, FORBIDDEN); return; } File file = new File(path); if (file.isHidden() || !file.exists()) { sendError(ctx, NOT_FOUND); return; } if (file.isDirectory()) { if (uri.endsWith("/")) { sendListing(ctx, file, uri); } else { sendRedirect(ctx, uri + '/'); } return; } if (!file.isFile()) { sendError(ctx, FORBIDDEN); return; } // Cache Validation String ifModifiedSince = request.headers().get(HttpHeaderNames.IF_MODIFIED_SINCE); if (ifModifiedSince != null && !ifModifiedSince.isEmpty()) { SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US); Date ifModifiedSinceDate; ifModifiedSinceDate = dateFormatter.parse(ifModifiedSince); long ifModifiedSinceDateSeconds = ifModifiedSinceDate.getTime() / 1000; long fileLastModifiedSeconds = file.lastModified() / 1000; if (ifModifiedSinceDateSeconds == fileLastModifiedSeconds) { sendNotModified(ctx); return; } } RandomAccessFile raf; try { raf = new RandomAccessFile(file, "r"); } catch (FileNotFoundException ignore) { sendError(ctx, NOT_FOUND); return; } long fileLength = raf.length(); HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK); HttpUtil.setContentLength(response, fileLength); setContentTypeHeader(response, file); setDateAndCacheHeaders(response, file); if (HttpUtil.isKeepAlive(request)) { response.headers().set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE); } ctx.write(response); ChannelFuture sendFileFuture; ChannelFuture lastContentFuture; if (ctx.pipeline().get(SslHandler.class) == null) { sendFileFuture = ctx.write(new DefaultFileRegion(raf.getChannel(), 0, fileLength), ctx.newProgressivePromise()); lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT); } else { sendFileFuture = ctx.writeAndFlush(new HttpChunkedInput(new ChunkedFile(raf, 0, fileLength, 8192)), ctx.newProgressivePromise()); lastContentFuture = sendFileFuture; } sendFileFuture.addListener(new ChannelProgressiveFutureListener() { @Override public void operationProgressed(ChannelProgressiveFuture future, long progress, long total) { if (total < 0) { System.err.println(future.channel() + " Transfer progress: " + progress); } else { System.err.println(future.channel() + " Transfer progress: " + progress + " / " + total); } } @Override public void operationComplete(ChannelProgressiveFuture future) { System.err.println(future.channel() + " Transfer complete."); } }); // Decide whether to close the connection or not. if (!HttpUtil.isKeepAlive(request)) { // Close the connection when the whole content is written out. lastContentFuture.addListener(ChannelFutureListener.CLOSE); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { cause.printStackTrace(); if (ctx.channel().isActive()) { sendError(ctx, INTERNAL_SERVER_ERROR); } } private static final Pattern INSECURE_URI = Pattern.compile(".*[<>&\"].*"); private static String sanitizeUri(String uri) { // Decode the path. try { uri = URLDecoder.decode(uri, "UTF-8"); } catch (UnsupportedEncodingException e) { throw new Error(e); } if (uri.isEmpty() || uri.charAt(0) != '/') { return null; } // Convert file separators. uri = uri.replace('/', File.separatorChar); System.out.println(uri); // Simplistic dumb security check. // You will have to do something serious in the production environment. if (uri.contains(File.separator + '.') || uri.contains('.' + File.separator) || uri.charAt(0) == '.' || uri.charAt(uri.length() - 1) == '.' || INSECURE_URI.matcher(uri).matches()) { return null; } // Convert to absolute path. return SystemPropertyUtil.get("user.dir") + File.separator + "website" + File.separator + uri; } private static final Pattern ALLOWED_FILE_NAME = Pattern.compile("[^-\\._]?[^<>&\\\"]*"); private static void sendListing(ChannelHandlerContext ctx, File dir, String dirPath) { FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK); response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=UTF-8"); StringBuilder buf = new StringBuilder().append("<!DOCTYPE html>\r\n") .append("<html><head><meta charset='utf-8' /><title>").append("Listing of: ").append(dirPath) .append("</title></head><body>\r\n") .append("<h3>Listing of: ").append(dirPath).append("</h3>\r\n") .append("<ul>").append("<li><a href=\"../\">..</a></li>\r\n"); for (File f : dir.listFiles()) { if (f.isHidden() || !f.canRead()) { continue; } String name = f.getName(); if (!ALLOWED_FILE_NAME.matcher(name).matches()) { continue; } buf.append("<li><a href=\"").append(name).append("\">").append(name).append("</a></li>\r\n"); } buf.append("</ul></body></html>\r\n"); ByteBuf buffer = Unpooled.copiedBuffer(buf, CharsetUtil.UTF_8); response.content().writeBytes(buffer); buffer.release(); // Close the connection as soon as the error message is sent. ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE); } private static void sendRedirect(ChannelHandlerContext ctx, String newUri) { FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, FOUND); response.headers().set(HttpHeaderNames.LOCATION, newUri); // Close the connection as soon as the error message is sent. ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE); } private static void sendError(ChannelHandlerContext ctx, HttpResponseStatus status) { FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, status, Unpooled.copiedBuffer("Failure: " + status + "\r\n", CharsetUtil.UTF_8)); response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain; charset=UTF-8"); // Close the connection as soon as the error message is sent. ctx.writeAndFlush(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 static void sendNotModified(ChannelHandlerContext ctx) { FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, NOT_MODIFIED); setDateHeader(response); // Close the connection as soon as the error message is sent. ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE); } /** * Sets the Date header for the HTTP response * * @param response * HTTP response */ private static void setDateHeader(FullHttpResponse response) { SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US); dateFormatter.setTimeZone(TimeZone.getTimeZone(HTTP_DATE_GMT_TIMEZONE)); Calendar time = new GregorianCalendar(); response.headers().set(HttpHeaderNames.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 static 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.headers().set(HttpHeaderNames.DATE, dateFormatter.format(time.getTime())); // Add cache headers time.add(Calendar.SECOND, HTTP_CACHE_SECONDS); response.headers().set(HttpHeaderNames.EXPIRES, dateFormatter.format(time.getTime())); response.headers().set(HttpHeaderNames.CACHE_CONTROL, "private, max-age=" + HTTP_CACHE_SECONDS); response.headers().set(HttpHeaderNames.LAST_MODIFIED, dateFormatter.format(new Date(fileToCache.lastModified()))); } /** * Sets the content type header for the HTTP Response * * @param response * HTTP response * @param file * file to extract content type */ private static void setContentTypeHeader(HttpResponse response, File file) { int dot_pos = file.getPath().lastIndexOf("."); if ((dot_pos > 0) && file.getPath().substring(dot_pos + 1).toLowerCase().equals("css")) { System.out.println(file.getPath().substring(dot_pos + 1)); response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/css"); return; } MimetypesFileTypeMap mimeTypesMap = new MimetypesFileTypeMap(); response.headers().set(HttpHeaderNames.CONTENT_TYPE, mimeTypesMap.getContentType(file.getPath())); } }