---
title: Multi-Utility FastAPI Server
emoji: 🌐
colorFrom: indigo
colorTo: blue
sdk: docker
sdk_version: "0.95.2"
app_file: main.py
pinned: false
---

# Multi-Utility FastAPI Server

A centralized, extensible FastAPI server providing reusable APIs with robust authentication, rate limiting, and logging.

[![Python 3.11+](https://img.shields.io/badge/python-3.11+-blue.svg)](https://www.python.org/downloads/)
[![FastAPI](https://img.shields.io/badge/FastAPI-0.104+-green.svg)](https://fastapi.tiangolo.com/)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)

## Features

- **Modular Architecture** - Easy to add new APIs
- **API Key Authentication** - Secure, timing-safe key validation
- **Rate Limiting** - Configurable per-endpoint limits with `slowapi`
- **Result Caching** - TTL-based caching with `cachetools`
- **Structured Logging** - Loguru with console/file output
- **Docker Ready** - Multi-stage, cache-optimized Dockerfile

## APIs

| API | Endpoint | Description |
|-----|----------|-------------|
| **Subtitles** | `POST /api/v1/subtitles/extract` | Transcribe YouTube video with Whisper ⚠️ |
| **Subtitles** | `POST /api/v1/subtitles/transcribe` | Transcribe uploaded audio with Whisper ✅ |
| **Embeddings** | `POST /api/v1/embeddings/generate` | Generate text embeddings (1024-dim) |

> ⚠️ **Note on HF Spaces:** The YouTube extraction endpoint (`/extract`) requires external network access and will **not work on Hugging Face Spaces** due to platform restrictions. Instead, use the **audio file upload endpoint** (`/transcribe`) which works perfectly on HF Spaces. For YouTube extraction, use a self-hosted deployment.

## Quick Start

### Local Development

```bash
# Install dependencies
poetry install

# Configure environment
cp .env.example .env
# Edit .env with your API keys

# Run server
poetry run uvicorn app.main:app --reload
```

### Docker

```bash
docker build -t multiutility-server .
docker run -p 7860:7860 -e API_KEYS=your-key multiutility-server
```

## Configuration

| Variable | Description | Default |
|----------|-------------|---------|
| `API_KEYS` | Comma-separated API keys (required) | - |
| `CORS_ORIGINS` | Allowed origins | `*` |
| `RATE_LIMIT_REQUESTS` | Requests per minute | `100` |
| `LOG_LEVEL` | Logging level | `INFO` |
| `WHISPER_MODEL` | Whisper model size | `base` |
| `EMBEDDING_MODEL` | HuggingFace model | `mixedbread-ai/mxbai-embed-large-v1` |

## API Usage

### Authentication

All endpoints (except health checks) require the `x-api-key` header:

```bash
curl -H "x-api-key: your-api-key" http://localhost:8000/api/v1/...
```

### Subtitles API

#### Extract from YouTube URL

> ⚠️ **Important:** This endpoint requires network access to YouTube and will **not work on Hugging Face Spaces**. Use the audio file upload endpoint below instead, or deploy on a self-hosted environment.

```bash
curl -X POST http://localhost:8000/api/v1/subtitles/extract \
  -H "Content-Type: application/json" \
  -H "x-api-key: your-key" \
  -d '{"url": "https://youtube.com/watch?v=VIDEO_ID", "lang": "en"}'
```

**Response:**
```json
{
  "status": "success",
  "video_id": "VIDEO_ID",
  "language": "en",
  "subtitles": ["Line 1", "Line 2", "..."]
}
```

#### Transcribe Audio File

> ✅ **Works everywhere:** This endpoint accepts direct audio file uploads and works in all environments including HF Spaces.

```bash
curl -X POST http://localhost:8000/api/v1/subtitles/transcribe \
  -H "x-api-key: your-key" \
  -F "file=@audio.mp3" \
  -F "lang=en"
```

**Supported formats:** mp3, wav, m4a, flac, ogg, webm

**Response:**
```json
{
  "status": "success",
  "language": "en",
  "file_name": "audio.mp3",
  "transcription": ["Segment 1", "Segment 2", "..."]
}
```

### Embeddings API

```bash
curl -X POST http://localhost:8000/api/v1/embeddings/generate \
  -H "Content-Type: application/json" \
  -H "x-api-key: your-key" \
  -d '{"texts": ["Hello world", "Another text"], "normalize": true}'
```

**Response:**
```json
{
  "status": "success",
  "embeddings": [[0.1, 0.2, ...], [0.3, 0.4, ...]],
  "model": "mixedbread-ai/mxbai-embed-large-v1",
  "dimensions": 1024
}
```

## Project Structure

```
app/
├── main.py                 # FastAPI application
├── core/                   # Config, logging, exceptions
├── middleware/             # Auth, rate limiting
└── apis/
    ├── subtitles/          # YouTube subtitle extraction
    └── embeddings/         # Text embedding generation
```

## Deployment

### Hugging Face Spaces

⚠️ **Network Limitation:** HF Spaces blocks external internet access, so YouTube downloads are not possible.

**What works on HF Spaces:**
- ✅ `/api/v1/subtitles/transcribe` - Upload audio files for transcription
- ✅ `/api/v1/embeddings/generate` - Generate text embeddings
- ❌ `/api/v1/subtitles/extract` - YouTube downloads (requires self-hosted deployment)

**Setup:**
1. Create a Docker Space
2. Set `API_KEYS` secret in Space settings
3. Push repository

**Recommended workflow for subtitles:**
1. Download audio locally using [yt-dlp](https://github.com/yt-dlp/yt-dlp): `yt-dlp -x --audio-format mp3 VIDEO_URL`
2. Upload the audio file to `/api/v1/subtitles/transcribe` endpoint
3. Receive transcription from Whisper

### Docker Compose

```bash
docker-compose up --build
```

## Alternative: Self-Hosted Deployment for YouTube Extraction

If you need YouTube subtitle extraction, deploy the server on a platform with internet access:

### Docker (VPS/Cloud VM)

```bash
docker build -t multiutility-server .
docker run -p 7860:7860 -e API_KEYS=your-key multiutility-server
```

### Cloud Platforms

- **Railway:** Direct Docker deployment
- **Render:** Connect GitHub repo, auto-deploy
- **DigitalOcean:** Deploy on Droplet ($4-12/month)
- **AWS/GCP/Azure:** Use ECS, Cloud Run, or App Service

### Benefits of Self-Hosted
- ✅ Direct YouTube access (no restrictions)
- ✅ Full control over resources
- ✅ No usage limits
- ✅ All features work natively

## Development

```bash
# Run tests
poetry run pytest

# Type checking
poetry run mypy app/

# Format code
poetry run black . && poetry run isort .
```

## License

MIT License - see [LICENSE](LICENSE) for details.