Class-based & Yield Dependencies
Learn to create more complex dependencies using classes and manage resources with `yield` for setup and teardown logic.
Beyond Simple Function Dependencies
In previous lessons, we learned about basic function-based dependencies in FastAPI. These are great for simple tasks like validation or injecting common values.
But what if your dependency needs to maintain state, accept configuration, or manage resources that require both setup and cleanup? That's where class-based and yield dependencies come in!
Why Use Class-Based Dependencies?
Class-based dependencies offer several advantages for more complex scenarios:
- Organization: Encapsulate related logic and data within a class.
- State: Classes can hold internal state, which can be useful (though be mindful of request isolation).
- Configuration: Easily pass parameters to the dependency during its instantiation.
- Testability: Easier to mock or inject specific class instances for testing.
All lessons in this course
- Understanding Dependencies in FastAPI
- Injecting Common Dependencies
- Class-based & Yield Dependencies
- Global Dependencies and Sub-Dependencies