PA1-JIDUNG-LO Overview

1. Name: JIDUNG, LO

2. Assignment name: PA1-JIDUNG-LO

3. Description of my assignment:

   Aspect	Description
   MyWebServer	- Initializes the server by parsing command-line arguments (document root and port). - Listens for incoming connections using ServerSocket. - Spawns a new thread (ClientHandler) for each client connection to handle requests concurrently. - Tracks active connections using AtomicInteger
   ClientHandler	- Implements Runnable to handle client requests in a separate thread. - Parse and validates HTTP requests (e.g., method, file path) - Sends requested file if they exist and accessible - Sends error pages for invalid or unauthorized requests (e.g., 404, 403, 400, 500) - Handles persistent connections (HTTP keep-alive) based on request headers and protocol
   MgrResponseDTO	- Generates HTTP responses with correct status code, heaeders, and body. - Handles different connection types (close/persistent) - Follow HTTP standards for responses
   MgrResponseCode	- Enum class that defines HTTP response codes and their corresponding messages.(e.g., 200 OK, 404 Not Found) - Ensure consistency in response code
   Log	- Logs events such as server start, client connections, request processing, and errors. - Writes logs to a file (tenet.log) with timestamps for tracking and debugging - Provides methods for logging different levels of messages (info, error) - Supports multithread-safe logging using synchronized methods
   Error Handling	- Provides error pages (e.g., 400.html,403.html,404.html,500.html) for invalid requests, file not found, or unauthorized access - Sends appropriate HTTP error responses to clients. - Logs errors for debugging and monitoring purposes
   Multithreading	- Handles concurrent client requests by running each in a separate thread (). ClientHandler - Ensures efficient connections even when multiple clients access the server simultaneously.

4. A list of submitted files

   File Path	File Name	Description
   src/main/java/org.example/tenet/	MyWebServer.java	Main class that initializes and starts the web server.
   src/main/java/org.example/tenet/	ClientHandler.java	Handles client requests and responses.
   src/main/java/org.example/tenet/	MgrResponseDTO.java	Generates HTTP responses with status codes and headers.
   src/main/java/org.example/tenet/	MgrResponseCode.java	Defines HTTP response codes and messages.
   src/main/java/org.example/tenet/	Log.java	Handles logging of server events.
   ./	tenet.log	Log file for server events.
   webSource/	400.html	Error page for bad requests.
   webSource/	403.html	Error page for forbidden access.
   webSource/	404.html	Error page for not found resources.
   webSource/	500.html	Error page for internal server errors.
   webSource/	index.html	Home Page** for https://www.scu.edu/
   webSource/	secret.html	Web page for testing access control. Be sure to change permission using chmod 000 PA1-JIDUNG-LO/webSource/secret.html before testing.
   webSource/	assets	Directory containing static files.
   webSource/	js	Directory containing JavaScript files.
   webSource/	livewhale	Directory containing JavaScript files.
   webSource/	media	Directory containing various images
   webSource/	public	Directory containing images and css

   Project Directory Structure:

   PA1-JIDUNG-LO/
   │
   ├── src/
   │   ├── main/
   │       ├── java/
   │       │   └── org/example/tenet/
   │       │       ├── MyWebServer.java       # Main class to initialize and start the web server
   │       │       ├── ClientHandler.java     # Handles client connections in separate threads
   │       │       ├── MgrResponseDTO.java    # Generates HTTP responses with headers and statuses
   │       │       ├── MgrResponseCode.java   # Enum for HTTP response codes and their messages
   │       │       └── Log.java               # Handles logging for server activities
   │       └── resources/
   │           └── static/snapshot/           # Snapshots of the web pages
   │               ├── page1.jpg
   │               ├── page2.jpg
   │               └── ...
   ├── webSource/
   │   ├── 400.html                           # Error page for "Bad Request"
   │   ├── 403.html                           # Error page for "Forbidden"
   │   ├── 404.html                           # Error page for "Not Found"
   │   ├── 500.html                           # Error page for "Internal Server Error"
   │   ├── index.html                         # Home page
   │   ├── secret.html                        # Page for testing access control
   │   ├── assets/                            # Directory for static assets (e.g., images, logos)
   │   ├── js/                                # Directory for JavaScript files
   │   ├── livewhale/                         # Directory for livewhale-related files
   │   ├── media/                             # Directory for images
   │   └── public/                            # Public directory for additional images and CSS
   │
   ├── tenet.log                              # Log file for server activities
   ├── run.sh                                 # Shortcut shell script to compile and run the server
   ├── README.md                              # Documentation for the project

5. Instructions for running tenet

   Dependencies

   Dependency	Version	Description
   OpenJDK	17.0.8	Java Development Kit for compiling and running the program.
   Operating System	Any	Works on Linux, macOS.
   CLI/Terminal	Any	Command-line interface to execute commands.

   Steps to run

   1. Ensure OpenJDK 17 is installed:

      Run the following command to install OpenJDK 17 if it is not already installed:

      sudo apt install openjdk-17-jdk

   2. Open terminal and navigate to the root directory of the PA1-JIDUNG-LO project:

       cd /path/to/PA1-JIDUNG-LO

   3. Compile the Java files using the following command:

      javac src/main/java/org/example/tenet/*.java

   4. If the compilation is successful, start the web server by running the following command:

      java -cp src/main/java org.example.tenet.MyWebServer -document_root "./webSource" -port 8888

      • _document_root "./webSource" specifies the directory containing the web files.

      • _port 8888 specifies the port number on which the server will listen for incoming connections.

      Note: run.sh combines Step 3 and Step 4 into a single script for convenience. If you want to save time, you can simply run:

      ./run.sh

      Make sure you are in the document root when running this script.

   5. Access the Web Server:

      • Open a web browser and navigate to http://localhost:8888/ to access the home page. This URL corresponds to the index.html file in the webSource/ directory.

   6. Additional information—Log and Testing:

      • Logs for server activities will be stored in the tenet.log file located in the project root. Open another terminal and run the following command to view the logs:

        tail -f tenet.log

      • To test 400.html, try http://localhost:8888 POST.
      • To test 403.html, first run:

        chmod 000 PA1-JIDUNG-LO/webSource/secret.html

        Then try http://localhost:8888/secret.html.
      • To test 404.html, try http://localhost:8888/pokemon.html.
      • To test 500.html, try http://localhost:8888/../secret.txt.

6. Snapshots of my web browser

   Snapshots of "http://localhost:8888/" Images

   Image 1	Image 2

7. Request Log Snapshot

8. Know Issues:

   1. Does not support HTTP methods other than GET.
   2. Limited to serving static content only; no dynamic page generation.
   3. Lacks HTTPS support.
   4. Port conflicts may occur; please ensure the specified port is available.

9. Logs Information

   • Client requests:
     • Timestamp.
     • Method (GET).
     • File/resource content type.
   • Responses:
     • Status codes.
     • Requested files.
     • Errors encountered (if any).
   • Connection of each Thread's start/shutdown times.