Using the database API

Safir-based applications that use a SQL database can use Safir to initialize that database and acquire a database session. Safir-based applications that use FastAPI can also use the Safir-provided FastAPI dependency to manage per-request database sessions. The Safir database support is based on SQLAlchemy and assumes use of PostgreSQL (possibly via Cloud SQL) as the underlying database.

Safir is an asyncio framework and requires using SQLAlchemy’s asyncio API. Safir uses the asyncpg PostgreSQL database driver.

Database support in Safir is optional. To use it, depend on safir[db] in your pip requirements.

Also see Configuring PostgreSQL and Redis DSNs for Pydantic types that help with configuring the PostgreSQL DSN.

Guides

• Initializing a database
• Using a database session in request handlers
• Creating a database session
• Handling datetimes in database tables
• Retrying database transactions
• Paginated queries
• Testing applications that use a database
• Managing schemas