Judge Server

The Judge Server is a REST API built using FastAPI for executing user code asynchronously. This server takes user-submitted code along with required parameters and assigns the execution tasks to workers via RabbitMQ. Upon completion, the workers make a POST request to callback URL provided in the request to return the status of the executed task.

This Judge Server is a wrapper REST api for the Judger System.

Features

• Asynchronous processing of user-submitted code.

• Uses RabbitMQ to assign tasks to workers.

• Horizontal scalability of workers.

• Callback mechanism to notify the status of task execution.

Horizontal Scalability

The system is designed to scale horizontally by adding more workers. Since tasks are assigned via RabbitMQ, you can easily add more worker instances to handle increased loads. Each worker listens to the same queue and processes tasks concurrently.

To add more workers, simply start additional instances of the worker process. Ensure that each worker is configured to connect to the same RabbitMQ server and listen to the same queue.

Technologies Used

Installation

Clone the project

git clone https://github.com/AbhishekBhosale46/OnlineJudge-JudgeServer

Install dependencies

pip install requirements.txt

Start the Judge Server

uvicorn server:app --host 127.0.0.1 --port 9000 --reload

Start the submit and run task worker

python worker/submit_worker.py
python worker/run_worker.py

Usage

Submitting a Task

To submit a task, make a POST request to the /submit or /run endpoint.

curl -X 'POST' \
  'http://127.0.0.1:8000/submit' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{
  "language": "string",
  "time_limit": 0,
  "memory_limit": 0,
  "src_code": "string",
  "std_in": " ",
  "expected_out": "string",
  "callback_url": "string"
}'

Receiving the Callback

The worker will execute the submitted code and send a POST request to the provided callback_url with the following JSON body:

{
  "status": "AC | WA | TLE | MLE | RE | CE",
}

API Reference

Make submit code request

  POST /submit

Parameter	Type	Description
language	string	Language of the source code
time_limit	int	Time limit in seconds
memory_limit	int	Memory limit in mb
src_code	string	Code to run on the server
std_in	string	Standard input to the program
expected_out	string	Expected output of the program
callback_url	string	Url where POST request will be made by worker

Make run code request

  POST /run

Parameter	Type	Description
language	string	Language of the source code
time_limit	int	Time limit in seconds
memory_limit	int	Memory limit in mb
src_code	string	Code to run on the server
std_in	string	Standard input to the program
callback_url	string	Url where POST request will be made by worker

Contributing

Contributions are welcome! Please fork the repository and submit a pull request for any improvements or bug fixes.

• Fork the repository.
• Create a new branch (git checkout -b feature-branch).
• Make your changes.
• Commit your changes (git commit -m 'Add some feature').
• Push to the branch (git push origin feature-branch).
• Open a pull request.