Request Body

✅ Request Body

When you need to send data from a client (let’s say, a browser) to your API, you send it as a request body.

Request body

data sent by the client to your API

Response body

data your API sends to the client

✅ Import Pydantic’s BaseModel

💡 to declare a request body, you use Pydantic

you need to import BaseModel from pydantic:

✅ Create your data model

decalre a data model as a class that inherits from BaseModel

class Person (BaseModel):
    name: str
    description: str
    age: float
    level: float

this will decalre a JSON object like

{
    "name": "So Hee",
    "description": "Glasses",
    "age": 27,
    "level": 3,
}

✅ Declare as a paramteter

@app.post("/persons/")
async def create_person(person: Person):
    return person

and declare as the type model you created, Person

☑️ Result

FastAPI will

• read the body of the request as JSON
• Convert the corresponding types and Validate the data
• Give you the recieved data in the parameter person

✅ Use the model

Inside the function, you can access all the attribute of the model object directly

@app.post("/persons/")
async def create_person(person: Person):
    person_dict= person.dict()
    if person.age:
        class = person.age+ person.level
        person_dict.update({"class": class})
    return person_dict

✅ Request body + path parameters

decalre path parameters and request body at the same time!

• function parameters that match path parameters should be taken from the path
• function parameters that are declared to be Pydantic models should be taken from the request body

@app.put("/persons/{person_id}")
async def create_person(person_id: int, person: Person):
    return {"person_id": person_id}

💟 reference

https://fastapi.tiangolo.com/ko/tutorial/body/