SimpleOJ

SimpleOJ is an interactive online platform for coding enthusiasts. It allows users to solve programming challenges and run code snippets in C, C++, Java, and Python.

Demo

For a visual demonstration of SimpleOJ in action, check out our video demo.

Features

User Capabilities

• Authentication: Users can log in using Google authentication, powered by PassportJS.
• Problem Management: Authenticated users can add, edit, and delete programming problems, complete with custom test cases.
• Code Execution: All users can run their code on the problem page. Code submissions and verifications are available for signed-in users.
• Submission Feedback: After submitting code, users receive immediate feedback on whether their solution is accepted, incorrect, or has timed out (TLE).
• History: Users can view their past submissions for each problem and view their code.
• Status: Users can see everyones recent submissions.

Running Code

SimpleOJ uses Node.js child processes to execute C, C++, Java and Python code. The execution is managed in the backend, ensuring secure and isolated runtime environments for each code snippet.

Technology Stack

• Frontend: Developed with ReactJS for a dynamic user interface.
• Backend: Built on NodeJS with Express, offering a robust server-side framework.
• Database: MongoDB is used for data storage, providing flexibility and scalability.
• Authentication: PassportJS manages user authentication, ensuring secure logins.
• Concurrency Management: Bull Queue is utilized to handle concurrent code execution requests efficiently.
• Containerization: Docker is used for containerizing the application, ensuring a consistent environment across different machines.

Future Goals

• Complexity Analysis: I aim to incorporate memory complexity analysis for running code. Resources and learning are underway for this implementation.

Local Setup

To get SimpleOJ up and running on your local machine, follow these instructions:

Prerequisites

• Ensure Docker is installed on your machine.
• Node.js and npm should be installed for managing dependencies.

Steps

1. Install Docker: If you haven't already, install Docker following the instructions here.

2. Clone Repository: Clone this repository to your local machine using git clone [repository-url].

3. Install Dependencies:

   • Navigate to the client directory in the terminal and run npm install to install all client-side dependencies.
   • Similarly, go to the server directory and run npm install for server-side dependencies.

4. Set Up Environment Variables:

   • In the server directory, create a .env file.
   • Add the following environment variables:

     GOOGLE_CLIENT_ID=your_google_client_id
     GOOGLE_CLIENT_SECRET=your_google_client_secret
     

     Replace your_google_client_id and your_google_client_secret with your actual Google client ID and secret.

5. Start the Application:

   • From the root directory of the project, run docker compose up in the terminal. This will set up the necessary Docker containers.
   • Optionally, you can run the client and server separately by navigating to their respective directories and executing npm start in each.

6. Accessing SimpleOJ:

   • Once everything is up and running, your local instance of SimpleOJ should be accessible. The client will typically run on http://localhost:3000, and the server will run on http://localhost:5000.

Troubleshooting

• If you encounter any issues during the setup, ensure all the environment variables are correctly set and that Docker is running properly.
• For any dependency-related issues, try removing the node_modules folder in the client and server directories, and run npm install again. gi

Support and Contact

For any assistance or inquiries, feel free to connect with me on LinkedIn.