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Questions tagged [pydantic]

Pydantic is a library for data validation and settings management based on Python type hinting and variable annotations. You can use Pydantic for defining schemas of complex structures in Python.

Pydantic is a library for data validation and settings management based on Python type hinting (PEP484) and variable annotations (PEP526). It allows for defining schemas in Python for complex structures.

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Can I override fields from a Pydantic parent model to make them optional?

I have two pydantic classes like this. class Parent(BaseModel): id: int name: str email: str class ParentUpdate(BaseModel): id: Optional[int] name: Optional[str] email: Optional[str] Both of these are practically the same…
Shiladitya Bose
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How to parse ObjectId in a pydantic model?

I am trying to parse MongoDB records to a pydantic model but failing to do so for ObjectId From what I understood, I need to setup validator for ObjectId and did try to both extend ObjectId class and add the validator decorator to my class using…
roshii
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How to use values from list as pydantic validator?

I would like to create pydantic model to validate users form. one of my model values should be validated from a list of names. I succeed to create the model using enum as follow: from enum import Enum class Fruit(str, Enum): APPLE = 'apple' …
OrFeldman
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How do add an assembled field to a Pydantic model

Say I have model class UserDB(BaseModel): first_name: Optional[str] = None last_name: Optional[str] = None How do I make another model that is constructed from this one and has a field that changes based on the fields in this model? For…
Florian van Kampen-Wright
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Pydantic validations for extra fields that not defined in schema

I am using pydantic for schema validations and I would like to throw an error when any extra field is added to a schema that isn't defined. from typing import Literal, Union from pydantic import BaseModel, Field, ValidationError class…
mc-user
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FastApi returns "field required" and "value_error.missing" for one of my parameters, but the field is there

I do a Post with some parameters, but one of them returns "field required" and "value_error.missing", but the field is there and it has a value. See the output of Postman. In schemas.py the fields are defined as follows: class Message(BaseModel): …
zappfinger
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Can I get incoming extra fields from Pydantic?

I have defined a pydantic Schema with extra = Extra.allow in Pydantic Config. Is it possible to get a list or set of extra fields passed to the Schema separately. For ex: from pydantic import BaseModel as pydanticBaseModel class…
Jyotirmay
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Syntax Error with flake8 and Pydantic Constrained Types: constr(regex=)

I use in Python the package pydantic and the linker Flake8. I want to use constr from pydantic with a regular Experssion. Only certain Characters should be passed. (a-z, A-Z, 0-9 and _) The regular Experssion "^[a-zA-Z0-9_]*$" works, but flake8…
Phil997
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How to use nested pydantic models for sqlalchemy in a flexible way

from fastapi import Depends, FastAPI, HTTPException, Body, Request from sqlalchemy import create_engine, Boolean, Column, ForeignKey, Integer, String from sqlalchemy.ext.declarative import declarative_base from sqlalchemy.orm import Session,…
j-gimbel
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FastAPI - ENUM type models not populated

Below is my fastAPI code from typing import Optional, Set from fastapi import FastAPI from pydantic import BaseModel, HttpUrl, Field from enum import Enum app = FastAPI() class Status(Enum): RECEIVED = 'RECEIVED' CREATED = 'CREATED' …
VamsiKrishna
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Python Pydantic - how to have an "optional" field but if present required to conform to not None value?

I am trying to validate an object that has "optional" fields in the sense that they may or may not be present. But when they are present, the fields should conform to a specific type definition (not None). In the example below, the "size" field is…
mgcdanny
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How can mypy accept pydantic's constr() types?

I have this code: from pydantic import BaseModel, constr DeptNumber = constr(min_length=6, max_length=6) class MyStuff(BaseModel): dept: DeptNumber ms = MyStuff(dept = "123456") deptnr.py:6: error: Variable "deptnr.DeptNumber" is not valid…
Robert
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Alter field after instantiation in Pydantic BaseModel class

With a Pydantic class as follows, I want to transform the foo field by applying a replace operation: from typing import List from pydantic import BaseModel class MyModel(BaseModel): foo: List[str] my_object =…
Jivan
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Generate dynamic model using pydantic

I am trying to create a dynamic model using Python's pydantic library. My input data is a regular dict. However, the content of the dict (read: its keys) may vary. I am wondering how to dynamically create a pydantic model which is dependent on the…
Andi
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FastAPI / Pydantic circular references in separate files

I would love to use a schema that looks something like the following in FastAPI: from __future__ import annotations from typing import List from pydantic import BaseModel class Project(BaseModel): members: List[User] class User(BaseModel): …
Nils Ziehn
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