Request body declaration in FastAPI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a request body parameter in FastAPI.

FastAPI

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()

class Item(BaseModel):
    name: str
    price: float

@app.post("/items/")
async def create_item(item: [1]):
    return item

Drag options to blanks, or click blank then click option'

AItem

BRequest

CBody

Dstr

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Request' instead of the Pydantic model.

Using 'Body' without importing or proper context.

Using primitive types like 'str' for complex data.

In FastAPI, to declare a request body, you define a Pydantic model (here, Item) and use it as the type of the parameter.

2fill in blank

medium

Complete the code to import the correct function to declare a request body explicitly.

FastAPI

from fastapi import FastAPI, [1]
from pydantic import BaseModel

app = FastAPI()

class User(BaseModel):
    username: str
    email: str

@app.post("/users/")
async def create_user(user: User = [1]()):
    return user

Drag options to blanks, or click blank then click option'

ADepends

BRequest

CBody

DForm

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Request' which is for the entire HTTP request, not just the body.

Using 'Depends' which is for dependency injection.

Using 'Form' which is for form data.

The Body function from FastAPI is used to explicitly declare a request body parameter with additional options.

3fill in blank

hard

Fix the error in the code to correctly declare a request body with a default value.

FastAPI

from fastapi import FastAPI, Body
from pydantic import BaseModel

app = FastAPI()

class Product(BaseModel):
    name: str
    price: float

@app.post("/products/")
async def create_product(product: Product = [1]):
    return product

Drag options to blanks, or click blank then click option'

ABody()

BBody(default=...)

CBody(default=Product())

DBody(default=None)

Attempts:

3 left

💡 Hint

Common Mistakes

Using Body(default=None) which makes the body optional.

Using Body() without specifying required or default.

Trying to instantiate the model as default.

Using Body(default=...) tells FastAPI that this parameter is required in the request body.

4fill in blank

hard

Fill both blanks to declare a request body with an alias and description.

FastAPI

from fastapi import FastAPI, Body
from pydantic import BaseModel

app = FastAPI()

class Order(BaseModel):
    item_id: int
    quantity: int

@app.post("/orders/")
async def create_order(order: Order = Body([1], description=[2])):
    return order

Drag options to blanks, or click blank then click option'

A...

B'Order data'

C'order_data'

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using None instead of ... for required body.

Putting alias string in the first blank instead of description.

Not providing description string.

Using ... marks the body as required, and description adds helpful info for API docs.

5fill in blank

hard

Fill all three blanks to declare a request body with an alias, example, and minimum value validation.

FastAPI

from fastapi import FastAPI, Body
from pydantic import BaseModel, Field

app = FastAPI()

class Payment(BaseModel):
    amount: float = Field(..., gt=0)
    method: str

@app.post("/payments/")
async def create_payment(payment: Payment = Body(
    ...,
    alias=[1],
    example=[2],
    description=[3]
)):
    return payment

Drag options to blanks, or click blank then click option'

A'payment_info'

B{"amount": 100.0, "method": "credit_card"}

C"Payment details with positive amount"

D"payment"

Attempts:

3 left

💡 Hint

Common Mistakes

Using alias as a dictionary instead of string.

Not providing example as a dictionary.

Using description as a non-string.

The alias is a string used in the JSON key, example shows sample data, and description explains the parameter.