response_model.py

from fastapi import FastAPI
from pydantic import BaseModel, EmailStr
import uvicorn

app = FastAPI()

"""
# Return the same input data

class Item(BaseModel):
    name: str
    email: EmailStr
    description: str | None = None
    price: float
    tax: float | None = None
    tags: list[str] = []


@app.post("/items/", response_model=Item)
async def create_item(item: Item):
    return item

# Add an output model

class UserIn(BaseModel):
    username: str
    password: str
    email: EmailStr
    full_name: str | None = None


class UserOut(BaseModel):
    username: str
    email: EmailStr
    full_name: str | None = None


@app.post("/user/", response_model=UserOut)
async def create_user(user: UserIn):
    return user
"""

# Response Model encoding parameters

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float = 10.5


items = {
    "foo": {
        "name": "Foo",
        "price": 50.2},
    "bar": {
        "name": "Bar",
        "description": "The Bar fighters",
        "price": 62,
        "tax": 20.2},
    "baz": {
        "name": "Baz",
        "description": "There goes my baz",
        "price": 50.2,
        "tax": 10.5,
    },
}


@app.get(
    "/items/{item_id}/name",
    response_model=Item,
    response_model_include=["name", "description"],
)
async def read_item_name(item_id: str):
    return items[item_id]


@app.get("/items/{item_id}/public", response_model=Item, response_model_exclude=["tax"])
async def read_item_public_data(item_id: str):
    return items[item_id]

if __name__ == '__main__':
    uvicorn.run(app, port=8000, host='127.0.0.1')