Saturday, January 31, 2015

Simple web server provide image download, using org.apache.http.protocol.HttpService

Last post show a "Simple web server using org.apache.http.protocol.HttpService". In this post, I tried to provide image download, by visiting http://<ip address>:8080/image

But FAIL - As shown in the video, sometimes the download will fail. And once fail, the code will block and have to be re-start. Hope anybody can advise.


Modify MainActivity.java
package com.example.androidhttpservice;

import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.util.Enumeration;

import org.apache.http.HttpEntity;
import org.apache.http.HttpException;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.entity.ContentProducer;
import org.apache.http.entity.EntityTemplate;
import org.apache.http.entity.FileEntity;
import org.apache.http.impl.DefaultConnectionReuseStrategy;
import org.apache.http.impl.DefaultHttpResponseFactory;
import org.apache.http.impl.DefaultHttpServerConnection;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.BasicHttpProcessor;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpRequestHandler;
import org.apache.http.protocol.HttpRequestHandlerRegistry;
import org.apache.http.protocol.HttpService;
import org.apache.http.protocol.ResponseConnControl;
import org.apache.http.protocol.ResponseContent;
import org.apache.http.protocol.ResponseDate;
import org.apache.http.protocol.ResponseServer;

import android.support.v7.app.ActionBarActivity;
import android.widget.TextView;
import android.os.Bundle;
import android.os.Environment;

/*
 * Permission needed:
 * "android.permission.INTERNET"
 * "android.permission.READ_EXTERNAL_STORAGE"
 */

public class MainActivity extends ActionBarActivity {

 HttpServiceThread httpServiceThread;
 
 TextView infoIp;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  infoIp = (TextView) findViewById(R.id.infoip);
  infoIp.setText(getIpAddress() + ":" 
    + HttpServiceThread.HttpServerPORT + "\n");

  httpServiceThread = new HttpServiceThread();
  httpServiceThread.start();
 }

 @Override
 protected void onDestroy() {
  super.onDestroy();
  httpServiceThread.stopServer();
 }

 private String getIpAddress() {
  String ip = "";
  try {
   Enumeration<NetworkInterface> enumNetworkInterfaces = NetworkInterface
     .getNetworkInterfaces();
   while (enumNetworkInterfaces.hasMoreElements()) {
    NetworkInterface networkInterface = enumNetworkInterfaces
      .nextElement();
    Enumeration<InetAddress> enumInetAddress = networkInterface
      .getInetAddresses();
    while (enumInetAddress.hasMoreElements()) {
     InetAddress inetAddress = enumInetAddress.nextElement();

     if (inetAddress.isSiteLocalAddress()) {
      ip += "SiteLocalAddress: "
        + inetAddress.getHostAddress() + "\n";
     }

    }

   }

  } catch (SocketException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
   ip += "Something Wrong! " + e.toString() + "\n";
  }

  return ip;
 }

 private class HttpServiceThread extends Thread {

  ServerSocket serverSocket;
  Socket socket;
  HttpService httpService;
  BasicHttpContext basicHttpContext;
  static final int HttpServerPORT = 8080;
  boolean RUNNING = false;

  HttpServiceThread() {
   RUNNING = true;
   startHttpService();
  }

  @Override
  public void run() {

   try {
    serverSocket = new ServerSocket(HttpServerPORT);
    serverSocket.setReuseAddress(true);

    while (RUNNING) {
     socket = serverSocket.accept();
     
     DefaultHttpServerConnection httpServerConnection = new DefaultHttpServerConnection();
     httpServerConnection.bind(socket, new BasicHttpParams());
     httpService.handleRequest(httpServerConnection,
       basicHttpContext);
     httpServerConnection.shutdown();
    }
    serverSocket.close();
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   } catch (HttpException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }

  private synchronized void startHttpService() {
   BasicHttpProcessor basicHttpProcessor = new BasicHttpProcessor();
   basicHttpContext = new BasicHttpContext();

   basicHttpProcessor.addInterceptor(new ResponseDate());
   basicHttpProcessor.addInterceptor(new ResponseServer());
   basicHttpProcessor.addInterceptor(new ResponseContent());
   basicHttpProcessor.addInterceptor(new ResponseConnControl());

   httpService = new HttpService(basicHttpProcessor,
     new DefaultConnectionReuseStrategy(),
     new DefaultHttpResponseFactory());

   HttpRequestHandlerRegistry registry = new HttpRequestHandlerRegistry();
   registry.register("/", new HomeCommandHandler());
   registry.register("/image", new ImageCommandHandler());
   httpService.setHandlerResolver(registry);
  }

  public synchronized void stopServer() {
   RUNNING = false;
   if (serverSocket != null) {
    try {
     serverSocket.close();
    } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }
   }
  }

  class HomeCommandHandler implements HttpRequestHandler {

   @Override
   public void handle(HttpRequest request, HttpResponse response,
     HttpContext httpContext) throws HttpException, IOException {

    HttpEntity httpEntity = new EntityTemplate(
      new ContentProducer() {

       public void writeTo(final OutputStream outstream)
         throws IOException {

        OutputStreamWriter outputStreamWriter = new OutputStreamWriter(
          outstream, "UTF-8");
        String response = "<html><head></head><body><h1>Hello HttpService, from Android-er<h1></body></html>";

        outputStreamWriter.write(response);
        outputStreamWriter.flush();
       }
      });
    response.setHeader("Content-Type", "text/html");
    response.setEntity(httpEntity);
   }

  }
  
  class ImageCommandHandler implements HttpRequestHandler {

   @Override
   public void handle(HttpRequest request, HttpResponse response,
     HttpContext context) throws HttpException, IOException {

    File file = new File(
      Environment.getExternalStorageDirectory(), 
      "android-er_sketch.jpg");

                FileEntity fileEntity = new FileEntity(file, "image/jpg");
                response.setHeader("Content-Type", "application/force-download");
                response.setHeader("Content-Disposition","attachment; filename=image.jpg");
    response.setHeader("Content-Type", "image/jpg");
    response.setEntity(fileEntity);
   }
   
  }

 }

}

Layout file, activity_main.xml, refer to last post.

Permission of "android.permission.INTERNET" and "android.permission.READ_EXTERNAL_STORAGE" is needed in AndroidManifest.xml.

download filesDownload the files.