基于Netty的HTTP文件服务器
一个基于Netty的文件服务器。
【使用jar包为： netty-all-4.0.42.Final.jar】
- 启动类
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpRequestDecoder;
import io.netty.handler.codec.http.HttpResponseEncoder;
import io.netty.handler.stream.ChunkedWriteHandler;
public class HttpFileServer {
public static final String DEFAULT_URL = "/src/";
public void run (final int port, final String url) throws Exception {
EventLoopGroup bossGroup = new NioEventLoopGroup();
EventLoopGroup workerGroup = new NioEventLoopGroup();
try {
ServerBootstrap b = new ServerBootstrap();
b.group(bossGroup,workerGroup).channel(NioServerSocketChannel.class)
.childHandler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast("http-decoder", new HttpRequestDecoder());
ch.pipeline().addLast("http-aggregator", new HttpObjectAggregator(65536));
ch.pipeline().addLast("http-encoder", new HttpResponseEncoder());
ch.pipeline().addLast("http-chunked", new ChunkedWriteHandler());
ch.pipeline().addLast("fileServerHandler", new HttpFileServerHandler(url));
}
});
ChannelFuture future = b.bind("127.0.0.1", port);
System.out.println("HTTP 文件服务器已经启动， 网址为 http://127.0.0.1:" + port + url);
future.channel().closeFuture().sync();
} finally {
bossGroup.shutdownGracefully();
workerGroup.shutdownGracefully();
}
}
public static void main(String[] args) throws Exception{
int port = 8080;
if(args != null && args.length > 0) {
try {
port = Integer.valueOf(args[0]);
} catch (NumberFormatException e) {
e.printStackTrace();
}
}
String url = DEFAULT_URL;
if (args.length > 1)
url = args[1];
new HttpFileServer().run(port, url);
}
}
- 处理类
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.handler.codec.http.*;
import io.netty.handler.stream.ChunkedFile;
import io.netty.util.CharsetUtil;
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.util.Date;
import java.util.regex.Pattern;
public class HttpFileServerHandler extends SimpleChannelInboundHandler<FullHttpRequest> {
private final String url;
public HttpFileServerHandler(String url){
this.url=url;
}
@Override
public void channelRead0(ChannelHandlerContext ctx, FullHttpRequest request) throws Exception {
Date date1 = new Date();
System.out.println(date1);
// 解码失败 400
if (!request.getDecoderResult().isSuccess()) {
sendError(ctx, HttpResponseStatus.BAD_REQUEST);
return;
}
// 只支持get方法
if (request.getMethod() != HttpMethod.GET) {
sendError(ctx, HttpResponseStatus.METHOD_NOT_ALLOWED);
return;
}
//
final String uri = request.getUri();
// 处理Uri地址
final String path = sanitizeUri(uri);
if (path == null) {
sendError(ctx, HttpResponseStatus.FORBIDDEN);
return;
}
File file = new File(path);
// 如果文件不存在，或不可访问
if (file.isHidden() || !file.exists()) {
sendError(ctx, HttpResponseStatus.NOT_FOUND);
return;
}
// 如果请求是文件夹
if (file.isDirectory()) {
// 请求以 '/'结尾，列出该文件夹下的所有内容
if (uri.endsWith("/")) {
sendListing(ctx, file);
} else {
// 否则自动补全'/' 然后再重定向访问
sendRedirect(ctx, uri + '/');
}
return;
}
if (!file.isFile()) {
sendError(ctx, HttpResponseStatus.FORBIDDEN);
return;
}
RandomAccessFile randomAccessFile = null;
try {
randomAccessFile = new RandomAccessFile(file, "r");// 以只读的方式打开文件
} catch (FileNotFoundException fnfe) {
sendError(ctx, HttpResponseStatus.NOT_FOUND);
return;
}
long fileLength = randomAccessFile.length();
// 创建一个默认的Http响应
HttpResponse response = new DefaultHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);
// 设置响应文件大小
HttpHeaders.setContentLength(response, fileLength);
// 设置 content Type
setContentTypeHeader(response, file);
// 设置 keep alive
if (HttpHeaders.isKeepAlive(request)) {
response.headers().set(HttpHeaders.Names.CONNECTION, HttpHeaders.Values.KEEP_ALIVE);
}
ctx.write(response);
//通过Netty的ChunkedFile对象直接将文件写入发送到缓冲区中
ChannelFuture sendFileFuture = ctx.write(new ChunkedFile(randomAccessFile, 0, fileLength, 8192), ctx.newProgressivePromise());
sendFileFuture.addListener(new ChannelProgressiveFutureListener() {
@Override
public void operationProgressed(ChannelProgressiveFuture future, long progress, long total) {
if (total < 0) {
// total unknown
System.err.println("Transfer progress: " + progress);
} else {
System.err.println("Transfer progress: " + progress + " / " + total);
}
}
@Override
public void operationComplete(ChannelProgressiveFuture future) throws Exception {
System.out.println("Transfer complete. 共计用时： " + (new Date().getTime() - date1.getTime()));
}
});
ChannelFuture lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT);
//如果不支持keep-Alive，服务器端主动关闭请求
if (!HttpHeaders.isKeepAlive(request)) {
lastContentFuture.addListener(ChannelFutureListener.CLOSE);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
cause.printStackTrace();
if (ctx.channel().isActive()) {
sendError(ctx, HttpResponseStatus.INTERNAL_SERVER_ERROR);
}
}
private static final Pattern INSECURE_URI = Pattern.compile(".*[<>&\"].*");
/**
* 格式化uri并且获取路径
*
* @param uri
* @return
*/
private String sanitizeUri(String uri) {
try {
uri = URLDecoder.decode(uri, "UTF-8");
} catch (UnsupportedEncodingException e) {
try {
uri = URLDecoder.decode(uri, "ISO-8859-1");
} catch (UnsupportedEncodingException e1) {
throw new Error();
}
}
if (!uri.startsWith("/")) {
return null;
}
uri = uri.replace('/', File.separatorChar);
if (uri.contains(File.separator + '.') || uri.contains('.' + File.separator) || uri.startsWith(".")
|| uri.endsWith(".") || INSECURE_URI.matcher(uri).matches()) {
return null;
}
return System.getProperty("user.dir") + File.separator + uri;
}
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(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);
response.headers().set(HttpHeaders.Names.CONTENT_TYPE, "text/html; charset=UTF-8");
StringBuilder buf = new StringBuilder();
String dirPath = dir.getPath();
buf.append("\r\n");
buf.append(""</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
buf<span class="token punctuation">.</span><span class="token function">append</span><span class="token punctuation">(</span>dirPath<span class="token punctuation">)</span><span class="token punctuation">;</span>
buf<span class="token punctuation">.</span><span class="token function">append</span><span class="token punctuation">(</span><span class="token string">" 目录："</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
buf<span class="token punctuation">.</span><span class="token function">append</span><span class="token punctuation">(</span><span class="token string">" \r\n");
buf.append(""
);
buf.append(dirPath).append(" 目录：");
buf.append("\r\n");
buf.append(""
);
buf.append("链接：.. \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("链接：);
buf.append(name);
buf.append("\">");
buf.append(name);
buf.append(" \r\n");
}
buf.append("\r\n");
ByteBuf buffer = Unpooled.copiedBuffer(buf, CharsetUtil.UTF_8);
response.content().writeBytes(buffer);
buffer.release();
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
}
private static void sendRedirect(ChannelHandlerContext ctx, String newUri) {
FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.FOUND);
response.headers().set(HttpHeaders.Names.LOCATION, newUri);
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
}
private static void sendError(ChannelHandlerContext ctx, HttpResponseStatus status) {
FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, status,
Unpooled.copiedBuffer("Failure: " + status.toString() + "\r\n", CharsetUtil.UTF_8));
response.headers().set(HttpHeaders.Names.CONTENT_TYPE, "text/plain; charset=UTF-8");
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
}
private static void setContentTypeHeader(HttpResponse response, File file) {
MimetypesFileTypeMap mimeTypesMap = new MimetypesFileTypeMap();
response.headers().set(HttpHeaders.Names.CONTENT_TYPE, mimeTypesMap.getContentType(file.getPath()));
}
}
然后 浏览器输入：http://127.0.0.1:8080/src/ 可以测试
- — 注： 参考书籍： Netty权威指南（第2版）