Func To Web 0.9.13

Type hints → Web UI. Minimal-boilerplate web apps from Python functions.

func-to-web Demo

FuncToWeb is actively maintained and used in production by myself and the community (featured in Awesome Python). The current version (0.9.x) is stable and production-ready. Version 1.0.0 is in active development with major improvements including function chaining with shared context and cleaner architecture for long-term maintainability. Until then, only critical bug fixes will be released.

Quick Start (30 seconds)

pip install func-to-web

from func_to_web import run

def divide(a: float, b: float):
    return a / b

run(divide)

Open http://127.0.0.1:8000 → You have a working web app!

</td> <td width="50%">

Demo

</td> </tr> </table>

Complete Feature Overview

Complete documentation with examples and screenshots for each feature:

Input Types

Basic Types: int, float, str, bool, date, time
Special Types: Color, Email
File Uploads: File, ImageFile, DataFile, TextFile, DocumentFile
Dynamic Lists: list[Type] with add/remove buttons
Optional Fields: Type | None with toggle switches
Dropdowns: Static (Literal, Enum) or Dynamic (Dropdown(func))
Validation: Pydantic constraints (min/max, regex, list validation)

</td> <td width="50%">

Output Types

Images & Plots: Return PIL Images and Matplotlib figures
File Downloads: Return FileResponse for any file type
Tables: Return list[dict], list[tuple], Pandas, NumPy, or Polars DataFrames
Multiple Outputs: Return tuples/lists combining text, images, tables, and files

Features

Authentication: Username/password protection
Multiple Functions & Groups: Serve multiple functions with index page or organize them into collapsible groups
Dark Mode: Automatic theme switching
Server Options: Custom host, port, path and more
Large Files: Optimized streaming (GB+ files)
Progress Bars: Real-time upload/download tracking
Concurrency: Handles multiple heavy requests and users simultaneously.
Error Handling: Beautiful error messages

</td> </tr> </table>

Full Documentation API Reference

Perfect For

✅ Rapid Prototyping - From pure Python function to usable web interface in seconds.
✅ Image Processing - Upload, process, and download images with PIL/Pillow.
✅ Data Science & Reporting - Instantly publish Pandas/Polars DataFrames and matplotlib plots without frontend code.
✅ High-Performance File Transfer - Stream uploads and downloads at native network/disk speeds. Handles massive files efficiently with minimal memory footprint.
✅ Secure Internal Apps - Admin panels, dashboards, and team tools protected by built-in authentication.

Quick Examples

DIY AirDrop / LocalSend (Very Fast File Transfers)

from pathlib import Path
from func_to_web import run
from func_to_web.types import File

desktop_path = Path.home() / "Desktop"

def upload_files(
    files: list[File],
): 
    for f in files:
        print(f"Uploaded file: {f}")
    return "Files uploaded successfully!"

run(upload_files, auto_delete_uploads=False, uploads_dir=desktop_path)

Secure Admin Panel

Protect sensitive tools with built-in authentication in one line.

import subprocess
from typing import Literal
from func_to_web import run

# 🔒 MANDATORY: Use HTTPS (Nginx).

def restart_service(service: Literal['nginx', 'gunicorn', 'celery']):
    """Restarts a system service."""
    # check=True raises an error shown in the Web UI if the command fails
    subprocess.run(["sudo", "supervisorctl", "restart", service], check=True)
    return f"✅ Service {service} restarted."

run(restart_service, auth={"admin": "super_secret_password"})

QR Code Generator

Generate QR codes instantly from text.

import qrcode
from func_to_web import run

def make_qr(text: str):
    """Returns a QR code image for the given text."""
    return qrcode.make(text).get_image()

run(make_qr)

PDF Merger

Merge multiple PDF files into a single document instantly.

from io import BytesIO
from pypdf import PdfWriter
from func_to_web import run
from func_to_web.types import DocumentFile, FileResponse

def merge_pdfs(files: list[DocumentFile]):
    """Upload PDFs and get a single merged file back."""
    merger = PdfWriter()
    for pdf in files:
        merger.append(pdf)

    output = BytesIO()
    merger.write(output)
    
    return FileResponse(data=output.getvalue(), filename="merged.pdf")

run(merge_pdfs)

Check the examples/ folder for +20 complete examples (Covers all features)

Requirements

Core:

Python 3.10+
FastAPI, Uvicorn, Pydantic, Jinja2, python-multipart, itsdangerous

Optional (for extended functionality):

Pillow, Matplotlib, Pandas, NumPy, Polars

Development:

pytest, mkdocs, mkdocs-material

Run Tests

pytest tests/ -v

MIT License • Made by Beltrán Offerrall • Contributions welcome!

FuncToWeb

Install / Use

README