How to write comments for model properties in generated OpenApi doc (using pydantic model)?

[FrederikNygaardSvendsen]

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Example Code

from typing import List, Optional
from pydantic import BaseModel


class Log(BaseModel):
    level: str
    message: str
    timestamp: int
    properties: dict = None

class CreateLogRequestDto(BaseModel):
    loggroup: str
    stream: Optional[str] = None # I would like to add a comment for this property (stream) in the generated OpenAPi spec
    logs: List[Log]

Description

Hi Everyone!

I just started using FastApi a couple of days ago, and already have a microservice running in production. My question is regarding the auto generated OpenApi spec. I am using the pydantic BaseModel to declare a class, that represent the expected input (request). In the router function, i typehint that classtype for the input argument, and the generated OpenApi doc looks as expected.

However, i would love to be able to write some comments for some of the properties in the generated OpenApi spec for the request. Please see uploaded picture for reference.

Is it possible to do so, and how?

Regards,
Frederik

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.66.1

Python Version

3.8.3

Additional Context

No response

[panla]

the secrets are in Body, Query, Header, Path

example

from typing import Optional, List

from fastapi import Body, Query, Header, Path
from pydantic import BaseModel
from pydantic.fields import Field


class PatchUserParser(BaseModel):
    cellphone: Optional[str] = Body(None, title='cellphone', description='user`s phone', min_length=7, max_length=15)
    name: Optional[str] = Body(None, title='name', description='user`s name', min_length=2, max_length=60)

the code in fastapi.param_functions.py

def Body(  # noqa: N802
    default: Any,
    *,
    embed: bool = False,
    media_type: str = "application/json",
    alias: Optional[str] = None,
    title: Optional[str] = None,
    description: Optional[str] = None,
    gt: Optional[float] = None,
    ge: Optional[float] = None,
    lt: Optional[float] = None,
    le: Optional[float] = None,
    min_length: Optional[int] = None,
    max_length: Optional[int] = None,
    regex: Optional[str] = None,
    example: Any = Undefined,
    examples: Optional[Dict[str, Any]] = None,
    **extra: Any,
) -> Any: