Introduction to Dependency Injection In FastAPI
FastAPI is a modern web framework for building APIs with Python. One of the key features of FastAPI is its support for dependency injection. Dependency injection is a design pattern that allows for the decoupling of components in an application, making it easier to test and maintain code.
What is Dependency Injection?
Dependency injection is a software design pattern that allows developers to inject dependencies into a class or function. This means that instead of a component creating its own dependencies, they are provided from an external source. This makes it easier to test components in isolation and switch out dependencies as needed.
Dependency Injection in FastAPI
FastAPI provides built-in support for dependency injection through the use of Python type hints. By annotating parameters with the types of dependencies they require, FastAPI can automatically inject those dependencies when a route is called.
For example, consider the following FastAPI route:
from fastapi import FastAPI
app = FastAPI()
def get_user_data(user_id: int, db: Database):
user = db.get_user(user_id)
return {"user": user}
@app.get("/user/{user_id}")
def get_user(user_id: int):
return get_user_data(user_id, db)
In this example, the get_user_data function has two dependencies: user_id and db. When the get_user route is called, FastAPI automatically injects these dependencies into the function, allowing it to retrieve user data from the database.
Benefits of Dependency Injection in FastAPI
By using dependency injection in FastAPI, developers can create more modular and testable code. Dependencies can easily be swapped out for testing or different environments, and components can be easily reused across different parts of the application.
Overall, dependency injection is a powerful tool for building scalable, maintainable APIs with FastAPI.
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bring a complete FastAPI proect using FastAPI + Postgresql + SQLModel + JWT
keep going bro!
Please do make some advance content like realtime stuff with redis or any message broker
Thx