Loading nested settings

[dalefrancis88]

Initial Checks

• I have searched GitHub for a duplicate issue and I'm sure this is something new
• I have searched Google & StackOverflow for a solution and couldn't find anything
• I have read and followed the docs and still think this is a bug
• I am confident that the issue is with pydantic (not my code, or another library in the ecosystem like FastAPI or mypy)

Description

I am trying to load in nested settings using pydantic with the latest versions and yet it's still not loading in anything. It's as if it's not reading/seeing any environment variables properly. I pulled the example code from the last post here as well as refrencing the docs and i can get is to load the top level but not the nested values

pydantic/pydantic-settings#43

Been working through this for half the day and cannot for the life of me figure out the issue. I've even done fresh installs

Example Code

import os

from pydantic import BaseModel, BaseSettings

os.environ.setdefault("v0", "A")
os.environ.setdefault("v1", "B")
os.environ.setdefault("sub_model__v2", "C")

class SubModel(BaseModel):
    V2: str


class Settings(BaseSettings):
    v0: str
    V1: str
    sub_model: SubModel | None

    class Config:
        case_sensitive = True
        env_nested_delimiter = "__"

print(Settings().dict())
# {'v0': 'A', 'V1': 'B', 'sub_model': {'V2': 'C'}}

Python, Pydantic & OS Version

pydantic version: 1.10.4
            pydantic compiled: True
                 install path: C:\Users\xxxx\anaconda3\envs\py3109\Lib\site-packages\pydantic
               python version: 3.10.9 | packaged by conda-forge | (main, Jan 11 2023, 15:15:40) [MSC v.1916 64 bit (AMD64)]
                     platform: Windows-10-10.0.22000-SP0
     optional deps. installed: ['dotenv', 'typing-extensions']

Affected Components

• Compatibility between releases
• Data validation/parsing
• Data serialization - .model_dump() and .model_dump_json()
• JSON Schema
• Dataclasses
• Model Config
• Field Types - adding or changing a particular data type
• Function validation decorator
• Generic Models
• Other Model behaviour - model_construct(), pickling, private attributes, ORM mode
• Plugins and integration with other tools - mypy, FastAPI, python-devtools, Hypothesis, VS Code, PyCharm, etc.

[samuelcolvin]

Is this a duplicate of pydantic/pydantic-settings#27?

[dalefrancis88]

Possible, looks like it might just be the sub settings are not being loaded at all?

[samuelcolvin]

They definitely are as per pydantic/pydantic-settings#27.

[dalefrancis88]

@samuelcolvin So what is the resolution here? wait for the fix from #4498 or use a pre-release version?

[samuelcolvin]

I don't think #4498 is related.

Best to use the work around described in pydantic/pydantic-settings#27, e.g. NESTED__SUB_VAR1.

See also #4991 (comment)

[dalefrancis88]

@samuelcolvin sorry i typed that wrong, it was unintentional