TCP/IP Classroom Server

Multithreaded server-client application where multiple clients can send text and files via server

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Table of contents

• Introduction
• Features
• Prerequisities
• Usage

Introduction

The project aims to help students to develop the idea of how client-server applications run and communicate. It's a simple implementation of server-client architecture that aims to simulate a classroom using TCP-IP protocol. Where students are able to join a server within the same port that the server uses, send texts to each other, ask/answer questions, and send/receive files.

Features

• The whole implementation runs under TCP/IP protocol and on localhost.
• Server supports multi-clients up to 30. This can be modified via MAX_CLIENT_NUM in util.h.
• Server supports database functionality with SQLite3. Check out the Prerequisities.
• Server takes time for timeout. During the inactivity of 10 minutes, the server shuts itself. This can be modified via TIMEOUT in util.h.
• The packet size is 1 kilobyte. This can be modified via BUFF_SIZE in util.h.
• Each client supports multithreading for receiving and sending packets simultaneously.
• Students can send texts to each other through the server. This can also be mentioned as broadcasting.
• Students can ask, answer, and list all questions with defined commands. Check out the Usage.
• Students can transfer and list files through the server with defined commands. Check out the Usage.
• Students can list all current users on the server. The server keeps a list of active users in the database.

Prerequisities

Important

The project was written/tested on Ubuntu/Linux. Some of the libraries are only compatible with Unix-like operating systems. Therefore, it does not run on Windows.

SQLite3

To install from the command line:

  sudo apt install sqlite3

To verify the installation, check the software’s version:

  sqlite3 --version

Or you can check the official Downloads page to install the source code.

Usage

Warning

The whole project runs on localhost and has not been tested on distinct machines. Trying to run the server and clients on different machines can cause fatal errors and crash the program entirely.

Warning

./bin, ./bin/local and ./bin/remote folders are crucial for the project functionality especially for the database and file transfer functions. Do not modify, edit, or delete bin and its sub-folders.

To install and build the project:

  git clone https://github.com/CheesyFrappe/multithreaded-tcp-ip-chat-server.git
  cd multithreaded-tcp-ip-chat-server/src
  make

Run server on bin directory:

  cd bin
  ./server

Run client(s) on bin directory:

  cd bin
  ./client

There are several defined commands for the utilities. Each of the commands is described below:

• use help to list all command descriptions during the session.
• use quit to exit from the application.
• use ASK to ask a question.

  ASK who is the first king of Portugal?  

• use ANSWER to answer a question.

  ANSWER it is Afonso I  

• use LISTQUESTIONS to list all questions.

  LISTQUESTIONS

  (1) who is the first king of Portugal?
      Afonso I

  ENDQUESTIONS 

• use PUTFILE to upload a file to the server from bin/local folder.

  PUTFILE 1.jpeg
  [+]Uploaded ./local/1.jpeg 111817  

• use GETFILE to download a file from the server to bin/local folder.

  GETFILE 1.jpeg
  [+]FILE ./local/1.jpeg 111817  

• use LISTFILES to list all files held by the server.

  LISTFILES

  (1) 1.jpeg

  (2) operating_systems.pdf

  ENDFILES

• use LISTUSERS to list all active users on the server.

  LISTUSERS

  (1) emir

  (2) miguel

  ENDUSERS