How to parse list of models with Pydantic

python pydantic
Nymous picture Nymous · Apr 19, 2019 · Viewed 17.5k times · Source

I use Pydantic to model the requests and responses to an API.

I defined a User class:

from pydantic import BaseModel

class User(BaseModel):
  name: str
  age: int

My API returns a list of users which I retrieve with requests and convert into a dict:

users = [{"name": "user1", "age": 15}, {"name": "user2", "age": 28}]

How can I convert this dict to a list of User instances?

My solution for now is

user_list = []
for user in users:
  user_list.append(User(**user))

Answer

David Asaf picture David Asaf · Apr 4, 2020

This is now possible using parse_obj_as.

from pydantic import parse_obj_as

users = [
    {"name": "user1", "age": 15}, 
    {"name": "user2", "age": 28}
]

m = parse_obj_as(List[User], users)

Related questions

Pydantic: Make field None in validator based on other field's value

I'm using the pydantic BaseModel with a validator like this: from datetime import date from typing import List, Optional from pydantic import BaseModel, BaseConfig, validator class Model(BaseModel): class Config(BaseConfig): allow_population_by_alias = True fields = { "some_date": { "alias": "…

Read More
Python/Pydantic - using a list with json objects

I have a working model to receive a json data set using pydantic. The model data set looks like this: data = {'thing_number': 123, 'thing_description': 'duck', 'thing_amount': 4.56} What I would like to do is have a list of json …

Read More
fastapi form data with pydantic model

I am trying to submit data from html forms and on the validate it with pydantic model. Using this code from fastapi import FastAPI, Form from pydantic import BaseModel from starlette.responses import HTMLResponse app = FastAPI() @app.get("/form", response_…

Read More