com.ociweb.pronghorn.adapter.netty.impl.HttpStaticFileServerHandler.java Source code

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Here is the source code for com.ociweb.pronghorn.adapter.netty.impl.HttpStaticFileServerHandler.java

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package com.ociweb.pronghorn.adapter.netty.impl;
/*
 * 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.
 */

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.buffer.ByteBufUtil;
import io.netty.buffer.Unpooled;
import io.netty.buffer.UnpooledByteBufAllocator;
import io.netty.buffer.UnpooledHeapByteBuf;
import io.netty.buffer.WrappedByteBuf;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelProgressiveFuture;
import io.netty.channel.ChannelProgressiveFutureListener;
import io.netty.channel.DefaultFileRegion;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.DefaultHttpResponse;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpChunkedInput;
import io.netty.handler.codec.http.HttpHeaderNames;
import io.netty.handler.codec.http.HttpUtil;
import io.netty.handler.codec.http.HttpHeaderValues;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.LastHttpContent;
import io.netty.handler.ssl.SslHandler;
import io.netty.handler.stream.ChunkedFile;
import io.netty.handler.stream.ChunkedInput;
import io.netty.handler.stream.ChunkedNioFile;
import io.netty.handler.stream.ChunkedStream;
import io.netty.util.CharsetUtil;
import io.netty.util.internal.SystemPropertyUtil;

import javax.activation.MimetypesFileTypeMap;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
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.TimeZone;
import java.util.regex.Pattern;

import static io.netty.handler.codec.http.HttpMethod.*;
import static io.netty.handler.codec.http.HttpResponseStatus.*;
import static io.netty.handler.codec.http.HttpVersion.*;

/**
 * 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}.</li>
 * <li>Contents of {@code /file1.txt} is cached by the browser.</li>
 * <li>Request #2 for {@code /file1.txt} 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} 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 SimpleChannelInboundHandler<FullHttpRequest> {

    private static final String INDEX_HTML = "index.html";
    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, SystemPropertyUtil.get("user.dir"));

        if (path == null) {
            sendError(ctx, FORBIDDEN);
            return;
        }

        File file = new File(path);

        if (file.isHidden() || !file.exists()) {
            return;
        }

        if (file.isDirectory()) {
            if (uri.endsWith("/")) {
                sendListing(ctx, file);
            } else {
                sendRedirect(ctx, uri + '/');
            }
            return;
        }

        sendFile(ctx, request, file);
    }

    public static void sendFile(ChannelHandlerContext ctx, FullHttpRequest request, File file)
            throws ParseException, IOException {

        long lastModified = file.lastModified();
        String path = file.getPath();

        // 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 = 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 = 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 = file.length();

        beginHTTPResponse(ctx, request, lastModified, path, fileLength);

        // Write the content.
        ChannelFuture sendFileFuture;
        ChannelFuture lastContentFuture;
        if (ctx.pipeline().get(SslHandler.class) == null) {
            sendFileFuture = ctx.write(new DefaultFileRegion(raf.getChannel(), 0, fileLength),
                    ctx.newProgressivePromise());
            // Write the end marker.
            lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT);
        } else {
            FileInputStream input = new FileInputStream(file);

            byte[] data = new byte[(int) fileLength]; //big hack to convert into byteBuf        
            int pos = 0;
            int remaining = (int) fileLength;
            while (remaining > 0) {
                int len = input.read(data, pos, remaining);
                remaining -= len;
                pos += len;
            }

            sendFileFuture = ctx.write(Unpooled.wrappedBuffer(data), ctx.newProgressivePromise());
            lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT);
        }

        progressAndClose(request, sendFileFuture, lastContentFuture);
    }

    public static void beginHTTPResponse(ChannelHandlerContext ctx, FullHttpRequest request, long lastModified,
            String path, long fileLength) {
        HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);
        HttpUtil.setContentLength(response, fileLength);
        setContentTypeHeader(response, path);

        response.headers().set(HttpHeaderNames.TRANSFER_ENCODING, HttpHeaderValues.CHUNKED);

        setDateAndCacheHeaders(response, lastModified);
        if (HttpUtil.isKeepAlive(request)) {
            response.headers().set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);
        }

        // Write the initial line and the header.
        ctx.write(response);
    }

    public static void progressAndClose(FullHttpRequest request, ChannelFuture sendFileFuture,
            ChannelFuture lastContentFuture) {
        sendFileFuture.addListener(new ChannelProgressiveFutureListener() {
            @Override
            public void operationProgressed(ChannelProgressiveFuture future, long progress, long total) {
                if (total < 0) { // total unknown
                    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);
        }
    }

    private static final long STARTUP_TIME = System.currentTimeMillis();

    public static void sendResource(ChannelHandlerContext ctx, FullHttpRequest request, String name)
            throws ParseException, IOException {

        InputStream resourceAsStream = HttpStaticFileServerHandler.class.getResourceAsStream(name);
        if (null == resourceAsStream) {
            throw new FileNotFoundException("Unable to find resource: " + name);
        } else {
            System.err.println("found resource: " + name);
        }

        int fileLength = resourceAsStream.available();

        // String path = file.getPath();
        long lastModified = STARTUP_TIME - 3000;
        String path = name;

        // 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 = 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 = lastModified / 1000;
            if (ifModifiedSinceDateSeconds == fileLastModifiedSeconds) {
                sendNotModified(ctx);
                return;
            }
        }

        beginHTTPResponse(ctx, request, lastModified, path, fileLength);

        // Write the content.
        ChannelFuture sendFileFuture;
        ChannelFuture lastContentFuture;

        byte[] data = new byte[(int) fileLength]; //big hack to convert into byteBuf        
        int pos = 0;
        int remaining = fileLength;
        while (remaining > 0) {
            int len = resourceAsStream.read(data, pos, remaining);
            remaining -= len;
            pos += len;
        }

        resourceAsStream.close();

        sendFileFuture = ctx.write(Unpooled.wrappedBuffer(data), ctx.newProgressivePromise());
        lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT);

        progressAndClose(request, sendFileFuture, lastContentFuture);

    }

    @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(".*[<>&\"].*");

    public static String sanitizeUri(String uri, String root) {
        // 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);

        // 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.
        String separatorAndURI = uri.startsWith(File.separator) ? uri : (File.separator + uri);
        if (null == root) {
            if ("/".equals(uri)) {
                return separatorAndURI + INDEX_HTML;
            } else {
                return separatorAndURI;
            }
        }

        String originalPath = root + separatorAndURI;

        if ("/".equals(uri)) {
            String indexPath = originalPath + INDEX_HTML;
            if (new File(indexPath).exists()) {
                return indexPath;
            } else {
                System.out.println("did not find " + indexPath);
            }
        }
        return originalPath;
    }

    private static final Pattern ALLOWED_FILE_NAME = Pattern.compile("[A-Za-z0-9][-_A-Za-z0-9\\.]*");

    private static void sendListing(ChannelHandlerContext ctx, File dir) {
        FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK);
        response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=UTF-8");

        String dirPath = dir.getPath();
        StringBuilder buf = new StringBuilder().append("<!DOCTYPE html>\r\n").append("<html><head><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, long lastModified) {
        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(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, String path) {
        MimetypesFileTypeMap mimeTypesMap = new MimetypesFileTypeMap();
        ////////////////////////////////////////
        //NOTE: this does not work and behaves different between Java releases!!!!!
        ///////////////////////////////////////
        String contentType = mimeTypesMap.getContentType(path);
        //patching mistake from the above broken code.
        if (path.endsWith("css")) {
            contentType = "text/css";
        } else if (path.endsWith("html")) {
            contentType = "text/html";
        } else if (path.endsWith("jpg")) {
            contentType = "image/jpeg";
        }
        response.headers().set(HttpHeaderNames.CONTENT_TYPE, contentType);
    }
}