u8what-backend

Flask backend for u8what. Accepts food photos, runs YOLOv8 instance segmentation, persists detections in SQLite, and serves annotated assets for the front end at https://u8what.food.

• Front end: https://u8what.food (also available via https://u8what.lol and https://u8what.netlify.app)
• Front-end source: https://github.com/sbogde/u8what-front-end
• This repo: u8what-backend

Features

• Accepts uploads on /segment, runs the selected YOLOv8 model, stores results, and returns JSON with detections.
• Saves originals and segmented previews under uploads/, making them accessible via /uploads/<filename>.
• Persists segmentation metadata plus per-detection rows in u8what.db for later browsing.
• Exposes /logs for a paginated history of recent classifications.
• Provides maintenance helpers (/mkdirs, /mkdb) to bootstrap storage and database.
• Restricts CORS to trusted clients (http://localhost on any port, https://u8what.food, https://u8what.lol, https://u8what.netlify.app).
• Optional NSFW guard using nsfw-detector when an NSFW model path is provided.

Quick start (local)

# 1) Python env
python3 -m venv .venv && source .venv/bin/activate
python -m pip install --upgrade pip

# 2) Install dependencies
pip install -r requirements.txt  # add nsfw-detector if you plan to enable the safety filter

# 3) Ensure model weights are available (place *.pt files alongside app.py)
# e.g. cp /path/to/yolov8n-seg.pt .

# 4) Run the API
python app.py  # or: flask --app app.py run

# (optional) enable safety filter
export NSFW_MODEL_PATH=/path/to/nsfw_mobilenet2.224x224.h5
export NSFW_THRESHOLD=0.82  # tweak if needed

When FLASK_ENV=production is set, the app ensures uploads/ exists and creates the SQLite schema automatically.

API overview

• GET / – returns a basic health payload with flags for uploads and DB presence.
• POST /segment – multipart upload (image, optional model) that writes segmentation history and returns detections.
• GET /logs?page=1&page_size=10 – paginated segmentation history from u8what.db.
• POST /mkdirs – ensures upload directories exist.
• POST /mkdb – initializes the SQLite schema in u8what.db.
• GET /uploads/<filename> – serves stored originals or annotated previews.