NanoHttpd -返回压缩后的响应

Question

如何在NanoHttpd中启用GZIP压缩

Java代码(启动web服务器并为任何请求返回相同的默认响应)：

package com.example;

import java.io.*;
import java.nio.charset.Charset;

import fi.iki.elonen.NanoHTTPD;

import static fi.iki.elonen.NanoHTTPD.Response.Status.OK;
public class App extends NanoHTTPD {

    public App() throws IOException {
        super(8080);
        start(NanoHTTPD.SOCKET_READ_TIMEOUT, false);
    }

  public static void main(String[] args) {
    try {
        new App();
    } catch (IOException ioe) {
        System.err.println("Couldn't start server:\n" + ioe);
    }
  }

  @Override
  public Response serve(IHTTPSession session) {
    ByteArrayInputStream resBody = new ByteArrayInputStream(new byte[0]);
    try {
        resBody = new ByteArrayInputStream("{\"response\":1}".getBytes("UTF-8"));
    } catch (UnsupportedEncodingException ex) {
    }
    Response res = newChunkedResponse(OK, "application/json", resBody);

    res.setGzipEncoding(true);
    return res;
  }
}

这是一个请求：

GET / HTTP/1.1
Host: localhost:8080
Pragma: no-cache
Cache-Control: no-cache
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9,ru;q=0.8

生成此响应：

HTTP/1.1 200 OK 
Content-Type: application/json
Date: Tue, 28 Aug 2018 11:39:12 GMT
Connection: keep-alive
Transfer-Encoding: chunked

{"response":1}

有没有办法为NanoHttpd响应启用GZIP？

Answer 1

将类似以下内容添加到您的服务器：

protected boolean useGzipWhenAccepted(Response r) {
    return true;
}

也不需要使用res.setGzipEncoding(true);，因为它是自动调用的。

Answer 2

如果报头不包含{ 'Accept-Encoding‘:' gzip '}或者甚至不包含’Accept-Encoding‘报头，那么NanoHTTPD会默认设置useGzipEncode，因为false.To克服了这一点，你可以在外部对数据进行压缩，并将byte[]传递给响应。

public class Server extends NanoHTTPD {

  byte[] bArr;

  public Server(int port) {
    super(port);
  }

  @Override
  public Response serve(IHTTPSession session) {
    return newFixedLengthResponse(Response.Status.OK,"application/octect-stream",new ByteArrayInputStream(this.bArr),bArr.length);
  }

  public void compressWithGzip(byte[] bArr) {
    ByteArrayOutputStream bout = new ByteArrayOutputStream();
    try {
      GZIPOutputStream gzip = new GZIPOutputStream(bout);
      gzip.write(bArr,0,bArr.length);
      gzip.close();
      setByteArray(bout.toByteArray());
      bout.close();
    } catch (IOException e) {
      //TODO
    }
  }

  public void setByteArray(byte[] byteArray) {
    this.bArr = byteArray;
  }
}