[Solved] Given the code below, what will be the output when accessing /users/42?... Given the code below, what will be the output when accessing /users/42? | FastAPI

FastAPI - Dependency Injection

Given the code below, what will be the output when accessing /users/42?

from fastapi import FastAPI, Depends

app = FastAPI()

def get_user(user_id: int):
    return {"user_id": user_id, "name": "Alice"}

@app.get("/users/{user_id}")
def read_user(user_id: int, user: dict = Depends(get_user)):
    return user

A{"user_id": 42, "name": "Alice"}

BError: missing user_id parameter in get_user

C{"user": {"user_id": 42, "name": "Alice"}}

DError: Depends cannot pass path parameters automatically

Step-by-Step Solution

Solution:

Step 1: Analyze get_user dependency parameters
get_user expects a user_id parameter, but FastAPI cannot automatically pass path parameters to dependencies without explicit declaration.
Step 2: Understand dependency parameter injection
Depends does not automatically forward path parameters to dependency functions unless declared with matching parameters or using Depends with parameters.
Final Answer:
Error: missing user_id parameter in get_user -> Option B
Quick Check:
Dependency parameters must match or be provided [OK]

Quick Trick: Dependencies need explicit parameters to receive path values [OK]

Common Mistakes:

MISTAKES

Assuming dependencies get path params automatically
Not matching dependency function parameters
Expecting nested dict output without code support

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Given the code below, what will be the output when accessing /users/42?

Step 1: Analyze get_user dependency parameters

Step 2: Understand dependency parameter injection

Final Answer:

Quick Check:

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