MediaLore-Web-App/AGENTS.md

AGENTS.md

Project Overview

MediaLore is a self-hosted media library browser for images and videos. It provides a web UI for browsing, searching, tagging, and viewing media with thumbnail previews and doom-scroll/TikTok-style consumption.

Monorepo with two independent apps:

• backend/ — Python FastAPI server
• frontend/ — React SPA (TypeScript, Vite)

Tech Stack

Layer	Technology
Backend	Python 3.12+, FastAPI, Uvicorn
Database	SQLite via SQLAlchemy (async aiosqlite), WAL mode
Migrations	Alembic
Thumbnails	Pillow (images), ffmpeg (videos) — generated on-demand
File Watch	watchdog — live filesystem monitoring
Frontend	React 19, TypeScript 6, Vite 8, React Router 7, TanStack Query v5
Infra	Docker Compose (backend: Python 3.12-slim, frontend: Nginx Alpine)

Directory Structure

medialore-web-app/
├── docker-compose.yml        # Orchestration (backend, frontend, volumes)
├── .env.example              # MEDIA_ROOT env var template
├── backend/
│   ├── Dockerfile
│   ├── pyproject.toml        # Python package config (hatchling build)
│   ├── alembic.ini
│   ├── alembic/              # DB migrations
│   │   ├── env.py
│   │   └── versions/
│   └── app/
│       ├── main.py           # FastAPI app, CORS, lifespan, router registration
│       ├── config.py         # Pydantic Settings (DATABASE_URL, MEDIA_ROOT, THUMBNAIL_DIR)
│       ├── database.py       # SQLAlchemy async engine, session, WAL pragma
│       ├── models.py         # ORM models: Library, MediaItem, Tag, media_item_tags
│       ├── schemas.py        # Pydantic request/response schemas
│       ├── routers/
│       │   ├── libraries.py  # Library CRUD, browse, doom-scroll, scan-status, rescan
│       │   ├── media.py      # Media item get, file serve, thumbnail, tag assignment
│       │   ├── tags.py       # Tag CRUD, grouped by category
│       │   └── search.py     # Fuzzy filename + tag search
│       └── services/
│           ├── scanner.py    # Dir walk, SHA-256 hashing, moved file detection
│           ├── watcher.py    # watchdog event handler (create/move/delete)
│           └── thumbnails.py # Pillow + ffmpeg thumbnail generation
└── frontend/
    ├── Dockerfile            # Multi-stage: Node build + Nginx serve
    ├── nginx.conf            # SPA fallback, /api proxy to backend
    ├── package.json
    ├── tsconfig.json         # Root references
    ├── tsconfig.app.json     # App TS config
    ├── tsconfig.node.json    # Vite config TS config
    ├── vite.config.ts        # Vite + React plugin, dev proxy /api -> localhost:8000
    ├── eslint.config.js      # Flat config: JS + TS + React hooks + refresh
    ├── index.html
    ├── public/
    │   ├── favicon.svg
    │   └── icons.svg
    └── src/
        ├── main.tsx          # React entry point
        ├── App.tsx           # Router, QueryClient, sidebar, theme, responsive layout
        ├── index.css         # CSS custom properties for light/dark themes
        ├── api/
        │   └── client.ts     # Typed fetch wrapper; all endpoint functions
        ├── pages/
        │   ├── SearchPage.tsx
        │   ├── BrowserPage.tsx
        │   ├── SettingsPage.tsx
        ├── components/
        │   ├── FileBrowser/FileBrowser.tsx
        │   ├── MediaViewer/MediaViewer.tsx
        │   ├── DoomScrollViewer/DoomScrollViewer.tsx
        │   └── TagPanel/TagPanel.tsx
        └── assets/
            ├── hero.png
            └── vite.svg

Common Commands

Backend

# Install (from backend/)
pip install -e .

# Run dev server
cd backend && uvicorn app.main:app --reload --port 8000

# Generate a new Alembic migration
cd backend && alembic revision --autogenerate -m "description"

# Apply migrations
cd backend && alembic upgrade head

Frontend

# Install dependencies (from frontend/)
npm install

# Dev server (proxies /api to localhost:8000)
npm run dev

# Production build
npm run build

# Lint
npm run lint

# Preview production build
npm run preview

Docker

docker compose up -d

Environment Variables

Variable	Default	Purpose
DATABASE_URL	sqlite+aiosqlite:////data/medialore.db	SQLite connection string
MEDIA_ROOT	/media	Root path for media libraries
THUMBNAIL_DIR	/data/thumbnails	Cached thumbnail storage

Pydantic Settings reads from .env at startup (via model_config = {"env_file": ".env"}). For Docker, these are set in docker-compose.yml.

Database

SQLite with WAL mode and a 10-second busy timeout (see app/database.py:14-18). Tables are auto-created at startup via Base.metadata.create_all in the FastAPI lifespan.

Schema

• libraries: id, name, path (unique)
• media_items: id, library_id (FK), rel_path, filename, file_hash (SHA-256), media_type ("image" or "video"), size_bytes, missing, created_at, updated_at — unique on (library_id, rel_path)
• tags: id, name, category — unique on (name, category)
• media_item_tags: media_item_id (FK), tag_id (FK), composite PK

Migrations: Use Alembic. The initial migration is at backend/alembic/versions/0001_initial_schema.py.

API Conventions

All endpoints are prefixed with /api. All responses are JSON except /api/media/:id/file (binary stream) and /api/media/:id/thumbnail (JPEG).

Async Database Access

Routers use FastAPI's Depends injection with the get_db async generator from database.py:

from app.database import get_db

@router.get("/...")
async def endpoint(db: AsyncSession = Depends(get_db)):
    ...

Frontend API Client

All API calls go through the typed api object in frontend/src/api/client.ts. Use useQuery / useMutation from TanStack Query. Never call fetch directly from components.

import { api } from "../api/client";
import { useQuery } from "@tanstack/react-query";

const { data } = useQuery({
  queryKey: ["libraries", id, "browse", path],
  queryFn: () => api.libraries.browse(id, path),
});

Code Patterns & Conventions

Backend (Python)

• No linter configured — follow the existing style (4-space indent, snake_case)
• Models use SQLAlchemy 2.0-style mapped_column (not Column())
• Schemas use Pydantic BaseModel
• Service modules handle business logic; routers handle HTTP concerns
• Background scanning runs via asyncio.create_task; watchers run in separate threads via watchdog.Observer
• Logging: use logging.getLogger(__name__) — the app namespace has a StreamHandler configured in main.py

Frontend (TypeScript/React)

• ESLint flat config with strict TypeScript-ESLint rules
• Inline style={{ ... }} objects for CSS (no CSS modules, no Tailwind)
• TypeScript interfaces for all API types live in client.ts
• Components use useState/useEffect/useQuery hooks, not class components
• Theme state persisted in localStorage key "theme", applied as data-theme attribute
• Responsive via window.matchMedia("(max-width: 767px)") listener
• File/thumbnail URLs constructed with api.media.fileUrl(id) and api.media.thumbnailUrl(id) (not fetched)

TypeScript Configuration

• tsconfig.app.json: strict mode, noUnusedLocals, noUnusedParameters, erasableSyntaxOnly
• tsconfig.node.json: for vite.config.ts only
• Build command: tsc -b && vite build (type-check via project references)

Testing

There are no test files in this project. No test framework is configured. When adding tests:

• Frontend: consider Vitest (pairs with Vite) + React Testing Library
• Backend: consider pytest + pytest-asyncio + httpx (for FastAPI TestClient)
• No existing test commands in CI, so add them and consider a GitHub Action or similar

Docker / Deployment

• docker compose up -d starts both services
• Backend runs on port 8000 (internal), frontend Nginx on port 80 (mapped to 8085 on host)
• Nginx proxies /api/ to http://backend:8000
• Media paths from the host are volume-mounted into the container at /media
• Persistent data (DB, thumbnails) stored in Docker volume medialore-data

Important Notes

• No auth/authentication — CORS allows all origins, no login system
• Thumbnails are generated on first request and cached to disk (THUMBNAIL_DIR)
• The scanner computes SHA-256 hashes to detect moved/renamed files and avoid re-processing
• File watcher uses watchdog with per-library PollingObserver (necessary for Docker volumes)
• media_items.missing flag is set when a scanned file no longer exists on disk
• The frontend build command runs tsc -b first, which checks types across project references — type errors will block the build