Source Code Socket Programming

Berikut contoh source code dari socket programming yang diimplementasikan dalam beberapa bahasa:

1. C
Model server-client dapat diimplementasikan menggunakan 2 source code, souce code untuk server dan client.

Server Source Code:
#include<stdio.h>
#include<netinet/in.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netdb.h>
#include<stdlib.h>
#include<string.h>
#define MAX 80
#define PORT 43454
#define SA struct sockaddr
void func(int sockfd)
{
char buff[MAX];
int n;
for(;;)
{
bzero(buff,MAX);
read(sockfd,buff,sizeof(buff));
printf("From client: %s\t To client : ",buff);
bzero(buff,MAX);
n=0;
while((buff[n++]=getchar())!='\n');
write(sockfd,buff,sizeof(buff));
if(strncmp("exit",buff,4)==0)
{
printf("Server Exit...\n");
break;
}
}
}
int main()
{
int sockfd,connfd,len;
struct sockaddr_in servaddr,cli;
sockfd=socket(AF_INET,SOCK_STREAM,0);
if(sockfd==-1)
{
printf("socket creation failed...\n");
exit(0);
}
else
printf("Socket successfully created..\n");
bzero(&servaddr,sizeof(servaddr));
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
servaddr.sin_port=htons(PORT);
if((bind(sockfd,(SA*)&servaddr, sizeof(servaddr)))!=0)
{
printf("socket bind failed...\n");
exit(0);
}
else
printf("Socket successfully binded..\n");
if((listen(sockfd,5))!=0)
{
printf("Listen failed...\n");
exit(0);
}
else
printf("Server listening..\n");
len=sizeof(cli);
connfd=accept(sockfd,(SA *)&cli,&len);
if(connfd<0)
{
printf("server acccept failed...\n");
exit(0);
}
else
printf("server acccept the client...\n");
func(connfd);
close(sockfd);
}

Client Source Code:
#include<stdio.h>
#include<netinet/in.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netdb.h>
#include<string.h>
#include<stdlib.h>
#define MAX 80
#define PORT 43454
#define SA struct sockaddr
void func(int sockfd)
{
char buff[MAX];
int n;
for(;;)
{
bzero(buff,sizeof(buff));
printf("Enter the string : ");
n=0;
while((buff[n++]=getchar())!='\n');
write(sockfd,buff,sizeof(buff));
bzero(buff,sizeof(buff));
read(sockfd,buff,sizeof(buff));
printf("From Server : %s",buff);
if((strncmp(buff,"exit",4))==0)
{
printf("Client Exit...\n");
break;
}
}
}

int main()
{
int sockfd,connfd;
struct sockaddr_in servaddr,cli;
sockfd=socket(AF_INET,SOCK_STREAM,0);
if(sockfd==-1)
{
printf("socket creation failed...\n");
exit(0);
}
else
printf("Socket successfully created..\n");
bzero(&servaddr,sizeof(servaddr));
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=inet_addr("127.0.0.1");
servaddr.sin_port=htons(PORT);
if(connect(sockfd,(SA *)&servaddr,sizeof(servaddr))!=0)
{
printf("connection with the server failed...\n");
exit(0);
}
else
printf("connected to the server..\n");
func(sockfd);
close(sockfd);
}

Setelah melakukan compile kedua source code pada terminal yang berbeda maka akan dibuat sebuah socket sehingga terminal server dan terminal client menjadi terhubung. Berikut tampilan pada kedua terminal ketika dua program dijalankan:

Program client akan meminta masukkan string, ketika dienter string akan dikirim ke terminal server, server juga dapat mengirimkan pesan untuk terminal client. Hal ini membukitkan bahwa kedua terminal terhubung.
(http://mcalabprogram.blogspot.com/2012/01/tcp-sockets-chat-applicationserver.html)

2. Java

Server Source Code:
 // File Name GreetingServer.java
import java.net.*;
import java.io.*;

public class GreetingServer extends Thread
{
   private ServerSocket serverSocket;
   public GreetingServer(int port) throws IOException
   {
      serverSocket = new ServerSocket(port);
      serverSocket.setSoTimeout(99999);
   }
   public void run()
   {
      while(true)
      {
         try
         {
            System.out.println("Waiting for client on port " + serverSocket.getLocalPort() + "...");
            Socket server = serverSocket.accept();
            System.out.println("Just connected to "+ server.getRemoteSocketAddress());
            DataInputStream in = new DataInputStream(server.getInputStream());
            System.out.println(in.readUTF());
            DataOutputStream out = new DataOutputStream(server.getOutputStream());
            out.writeUTF("Thank you for connecting to " + server.getLocalSocketAddress() + "\nGoodbye!");
            server.close();
         }catch(SocketTimeoutException s)
         {
            System.out.println("Socket timed out!");
            break;
         }catch(IOException e)
         {
            e.printStackTrace();
            break;
         }
      }
   }
   public static void main(String [] args)
   {
      int port = Integer.parseInt(args[0]);
      try
      {
         Thread t = new GreetingServer(port);
         t.start();
      }catch(IOException e)
      {
         e.printStackTrace();
      }
   }
}

Client Source Code:
 // File Name GreetingClient.java

import java.net.*;
import java.io.*;

public class GreetingClient
{
   public static void main(String [] args)
   {
      String serverName = args[0];
      int port = Integer.parseInt(args[1]);
      try
      {
         System.out.println("Connecting to " + serverName + " on port " + port);
         Socket client = new Socket(serverName, port);
         System.out.println("Just connected to " + client.getRemoteSocketAddress());
         OutputStream outToServer = client.getOutputStream();
         DataOutputStream out = new DataOutputStream(outToServer);
         out.writeUTF("Hello from " + client.getLocalSocketAddress());
         InputStream inFromServer = client.getInputStream();
         DataInputStream in = new DataInputStream(inFromServer);
         System.out.println("Server says " + in.readUTF());
         client.close();
      }catch(IOException e)
      {
         e.printStackTrace();
      }
   }
}

Jalankan kedua program kembali pada terminal yang berbeda, maka akan muncul tampilan seperti berikut:

Dengan memasukkan command : java GreetingServer <port yang ingin digunakan> pada terminal pertama, program akan membuat socket pada port yang telah dimasukkan pengguna.
Pada terminal kedua, masukkan command java GreetingClient localhost <port yang dimasukkan pada terminal server>.
Terminal Client akan meminta pada server untuk memberikan sambungan. Setelah disambungkan, baik client maupun server akan diberi pesan bahwa koneksi telah terhubung sebelumnya.
(http://www.tutorialspoint.com/java/java_networking.htm)

3. Python

Source Code Server:

#!/usr/bin/env python

# server.py

import socket

import select

import config as cfg

import Queue

from threading import Thread

from time import sleep

from random import randint

import sys

class ProcessThread(Thread):

    def __init__(self):

        super(ProcessThread, self).__init__()

        self.running = True

        self.q = Queue.Queue()

    def add(self, data):

        self.q.put(data)

    def stop(self):

        self.running = False

    def run(self):

        q = self.q

        while self.running:

            try:

                # block for 1 second only:

                value = q.get(block=True, timeout=1)

                process(value)

            except Queue.Empty:

                sys.stdout.write('.')

                sys.stdout.flush()

        #

        if not q.empty():

            print "Elements left in the queue:"

            while not q.empty():

                print q.get()

t = ProcessThread()

t.start()

def process(value):

    """

    Implement this. Do something useful with the received data.

    """

    print value

    sleep(randint(1,9))    # emulating processing time

def main():

    s = socket.socket()         # Create a socket object

    host = socket.gethostname() # Get local machine name

    port = cfg.PORT                # Reserve a port for your service.

    s.bind((host, port))        # Bind to the port

    print "Listening on port {p}...".format(p=port)

    s.listen(5)                 # Now wait for client connection.

    while True:

        try:

            client, addr = s.accept()

            ready = select.select([client,],[], [],2)

            if ready[0]:

                data = client.recv(4096)

                #print data

                t.add(data)

        except KeyboardInterrupt:

            print

            print "Stop."

            break

        except socket.error, msg:

            print "Socket error! %s" % msg

            break

    #

    cleanup()

def cleanup():

    t.stop()

    t.join()

#########################################################

if __name__ == "__main__":

    main()

Source Code Client:

#!/usr/bin/env python

# client.py

import config as cfg

import sys

import socket

def main(elems):

    try:

        for e in elems:

            client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

            host = socket.gethostname()

            client.connect((host, cfg.PORT))

            clientfff.send(e)

            client.shutdown(socket.SHUT_RDWR)

            client.close()

    except Exception as msg:

        print msg

#########################################################

if __name__ == "__main__":

    main(sys.argv[1:])

Siapkan satu file lagi yang akan digunakan untuk mengkonfigurasi port. File tersebut mengandung source code sbb:

# config.py
PORT=3030




Letakkan file tersebut pada directory yang sama dengan server.py. Lakukan compile pada file server.py pada terminal maka akan muncul tampilan sebagai berikut:

Tampilan diatas menunjukkan bahwa server sedang menunggu pesan yang akan dikirimkan client.

Langkah selanjutnya adalah mengcompile file client.py pada terminal lain menggunakan command : python client.py <pesan yang ingin dikirimkan>. Program client.py akan tersambung dengan server lalu mengirimkan pesannya. Berikut tampilan eksekusinya:

(http://pythonadventures.wordpress.com/2013/07/06/a-basic-socket-client-server-example/)