judge0-client 0.3.0

Simple Judge0 client for Python

Judge0 Client

Asynchronous Python client for the Judge0 API. Built on top of httpx with Pydantic models for requests and responses.

This library helps you submit code to a Judge0 instance and retrieve execution results with clear, typed models and convenient error handling.

Highlights

• Async, httpx-based client
• Pydantic models for request/response validation
• Single-file and multi-file submissions
• Fully automated Base64 handling for text fields and additional files
• Token-based auth header support

Requirements

• Python 3.10+
• A running Judge0 instance (public or self-hosted)

Installation

From PyPI:

pip install judge0-client

or

uv add judge0-client

Quick Start (async)

import asyncio
from judge0_client import Judge0Client, SingleFileSubmission


async def main() -> None:
    # On many instances, language_id=71 corresponds to Python 3
    req = SingleFileSubmission(
        language_id=71,
        source_code='print("Hello, Judge0!")',
    )

    async with Judge0Client(base_url="https://YOUR_JUDGE0_URL.com") as client:
        # 1) Create submission — returns token
        created = await client.create_submission(req)

        # 2) Poll result by token
        detail = await client.get_submission(created.token)
        print("STATUS:", detail.status.description)
        print("STDOUT:", detail.stdout)


if __name__ == "__main__":
    asyncio.run(main())

Documentation

• Project website
• API Reference

Usage

Client parameters

Judge0Client(
    base_url: str,                        # Base URL of your Judge0 instance (no trailing slash)
    timeout: float | httpx.Timeout = 10.0,
    auth_header: str = "X-Auth-Token",   # Custom auth header name if needed
    auth_token: str | SecretStr | None = None,  # Token value passed in the auth header
)

Notes:

• The client sets Accept: application/json and Content-Type: application/json headers.
• If auth_token is provided, it will be sent as {auth_header}: <token>.

Single-file submissions

from judge0_client import SingleFileSubmission

req = SingleFileSubmission(
    language_id=71,
    source_code="print('sum =', int(input()) + 2)",
    stdin="40\n",
)
# Then use it with the client as shown in the Quick Start.

You can attach additional files that will be zipped and Base64-encoded automatically:

from judge0_client import SingleFileSubmission

req = SingleFileSubmission(
    language_id=71,
    source_code="import helper; print(helper.answer())",
    additional_files={
        "helper.py": "def answer():\n    return 42\n",
    },
)

Multi-file submissions

Use MultiFileSubmission (language id=89 on Judge0 for multi-file/script-based runs). You must provide a run script in additional_files.

from judge0_client import MultiFileSubmission

req = MultiFileSubmission(
    # language_id is fixed to 89 in this model
    additional_files={
        # Required run script
        "run": "python main.py\n",
        # Your sources
        "main.py": "print('Hello from multi-file!')\n",
    },
)
# Then use it with the client as shown in the Quick Start.

Error handling

Network or HTTP errors raise Judge0Error with helpful context:

import asyncio
from judge0_client import Judge0Client, SingleFileSubmission, Judge0Error


async def main() -> None:
    try:
        async with Judge0Client(base_url="https://judge0.ce.pdn.ac.lk") as client:
            req = SingleFileSubmission(language_id=71, source_code="print('hi')")
            created = await client.create_submission(req)
            detail = await client.get_submission(created.token)
            print(detail.stdout)
    except Judge0Error as e:
        # Inspect message, status code, and response body (if any)
        print("Submission failed:", e)


if __name__ == "__main__":
    asyncio.run(main())

Tips

• Language IDs differ across Judge0 instances. Check your instance’s languages endpoint to confirm IDs.
• The client and models automatically handle Base64 encoding for text fields (source_code, stdin, expected_output) and additional files when required by Judge0.

Contributing

Contributions are welcome! Feel free to open an issue or a pull request.

License

MIT License — see LICENSE.