How could I return default value with response_model

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Example Code

from pydantic import BaseModel
from typing import List, Optional
from fastapi import FastAPI

app = FastAPI()

class Users(BaseModel):
    name: Optional[str] = 'No Username'

@app.get("/", response_model=List[Users])
async def get_users():
    users = [{'id':1, 'name':'abc'},{'id':2, 'name':None}]
    return users

Description

I want to return the imformation of all users. If an user didn’t set his name(None), then return ‘No username’.

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.66.1

Python Version

3.9.5

Additional Context

No response

[Honda-a]

I see then in that case you need to set your default value in the Model and use pydantic_model_creator it would be something like this

from tortoise.models import Model
from tortoise import fields
from tortoise.contrib.pydantic import pydantic_model_creator
class ModelUsers(Model):
    id = fields.IntField(pk=True)
    name = fields.TextField(null=True, default="No Username")

Users = pydantic_model_creator(ModelUsers, name="Users")

@app.get("/", response_model=List[Users])
async def get_users():
    users = await pydantic_model_creator.from_queryset(ModelUsers.all())
    return users

[skk294]

I see then in that case you need to set your default value in the Model and use pydantic_model_creator it would be something like this

from tortoise.models import Model
from tortoise import fields
from tortoise.contrib.pydantic import pydantic_model_creator
class ModelUsers(Model):
    id = fields.IntField(pk=True)
    name = fields.TextField(null=True, default="No Username")

Users = pydantic_model_creator(ModelUsers, name="Users")

@app.get("/", response_model=List[Users])
async def get_users():
    users = await pydantic_model_creator.from_queryset(ModelUsers.all())
    return users

Thank you. ^_^