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Web Database

Async and sync SQLAlchemy session factories.

Source: web/backend/database.py

Overview

Provides both async (for FastAPI request handlers) and sync (for Celery workers) SQLAlchemy session factories. Uses PostgreSQL via asyncpg.

Exports

Export	Type	Used By
`async_session_factory`	`async_sessionmaker`	FastAPI routers
`sync_session_factory`	`sessionmaker`	Celery tasks
`get_async_session()`	FastAPI Dependency	Router dependency injection
`get_sync_session()`	context manager	Celery task code

Why Two Factories?

Async — FastAPI handlers are async; SQLAlchemy’s async engine uses asyncpg for non-blocking DB calls
Sync — Celery workers run in separate processes; they use standard synchronous SQLAlchemy

Both connect to the same PostgreSQL database via different connection strings from Web Config.

Dependencies

Web Database
├── SQLAlchemy (async + sync)
├── asyncpg
├── Web Config         (DATABASE_URL, SYNC_DATABASE_URL)
├── DB Models          (table definitions)
└──▶ consumed by FastAPI App (lifecycle)
     ├──▶ Uploads Router
     ├──▶ Jobs Router
     ├──▶ Events Router
     └──▶ Pipeline Tasks