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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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Best way to specify nested dict with pydantic?

Context I'm trying to validate/parse some data with pydantic. I want to specify that the dict can have a key daytime, or not. If it does, I want the value of daytime to include both sunrise and sunset. e.g. These should be allowed: { 'type':…
falsePockets
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Is there any way to have multiple response models in FastAPI/OpenAPI?

I am writing an app where I need to have two completely different set of response structures depending on logic. Is there any way to handle this so that I can have two different response models serialized, validated and returned and reflect in…
Dhaval Savalia
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Pydantic constr vs Field args

I wanted to know what is the difference between: from pydantic import BaseModel, Field class Person(BaseModel): name: str = Field(..., min_length=1) And: from pydantic import BaseModel, constr class Person(BaseModel): name:…
asmartin
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Using FastAPI & Pydantic, how do I define an Optional field with a description

For a FastAPI Pydanctic class I have these values class ErrorReportRequest(BaseModel): sender: Optional[str] = Field(..., description="Who sends the error message.") error_message_displayed_to_client: str = Field(..., description="The error…
576i
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In JSON created from a pydantic.BaseModel exclude Optional if not set

I want to exclude all the Optional values that are not set when I create JSON. In this example: from pydantic import BaseModel from typing import Optional class Foo(BaseModel): x: int y: int = 42 z:…
Arpad Horvath -- Слава Україні
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How to validate a pydantic object after editing it

Is there any obvious to validate a pydantic model after some changing some attribute? Say I create a simple Model and object: from pydantic import BaseModel class A(BaseModel): b: int = 0 a=A() Then edit it, so that it is actually…
lordvlad
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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…
Bill Armstrong
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How to Define Class Attributes after Inheriting Pydantic's BaseModel?

In normal python classes I can define class attributes like class Example: x = 3 def __init__(self): pass And if I then do Example.x or Example().x, I get 3. When I inherit pydantic's BaseModel, I can't figure out how to define class…
Alan
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return pydantic model with field names instead of alias as fastapi response

I am trying to return my model with the defined field names instead of its aliases. class FooModel(BaseModel): foo: str = Field(..., alias="bar") @app.get("/") -> FooModel: return FooModel(**{"bar": "baz"}) The response will be {"bar":…
The Fool
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pydantic: Using property.getter decorator for a field with an alias

scroll all the way down for a tl;dr, I provide context which I think is important but is not directly relevant to the question asked A bit of context I'm in the making of an API for a webapp and some values are computed based on the values of others…
ewen-lbh
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Check if List is not empty with Pydantic in an elegant way

Let's say I have some BaseModel, and I want to check that it's options list is not empty. I can perfectly do it with a validator: class Trait(BaseModel): name: str options: List[str] @validator("options") def options_non_empty(cls,…
keddad
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How to parse and read "_id" field from and to a pydantic model?

I am trying to parse MongoDB data to a pydantic schema but fail to read its _id field which seem to just disappear from the schema. The issue is definitely related to the underscore in front of the object attribute. I can't change _id field name…
roshii
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FastAPI - Pydantic - Value Error Raises Internal Server Error

I am using FastAPI with Pydantic. My problem - I need to raise ValueError using Pydantic from fastapi import FastAPI from pydantic import BaseModel, validator from fastapi import Depends, HTTPException app = FastAPI() class RankInput(BaseModel): …
Rajath Rao - Software Engineer
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How to resolve pydantic model is not JSON serializable

I am having below pydantic models. class SubModel(BaseModel): columns: Mapping key: List[str] required: Optional[List[str]] class Config: anystr_strip_whitespace: True extra: Extra.allow …
Naxi
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Defining recursive models in Pydantic?

How can I define a recursive Pydantic model? Here's an example of what I mean: from typing import List from pydantic import BaseModel class Task(BaseModel): name: str subtasks: List[Task] = [] but when I run that I get the following…
A Poor
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