pydantic-external-settings-v1 0.0.1

provide a class descriptor for pydantic to load settings from external sources.compatible with pydantic 1.x

pydantic-external-settings-v1

This module provides a way to load settings from any external source, when using pydantic BaseSettings.

Quickstart

from pydantic_external_settings import ExternalSourceConfig
from pydantic import BaseSettings
from typing import ClassVar


class ApolloSourceConfig(ExternalSourceConfig):
    def __init__(self, validation_alias: str = None, *, default_value=None):
        super().__init__(self.get_from_apollo, validation_alias, default_value=default_value)

    def get_from_apollo(self, key):
        return key + "_***"


class S3Settings(BaseSettings):
    api_key: str = "api_key"
    bucket: ClassVar[str] = ApolloSourceConfig()

    class Config:
        env_file = '.env'


s3_settings = S3Settings()
print(s3_settings.bucket)

ExternalSourceConfig Usage

ExternalSourceConfig is a class descriptor, which can be used to load settings from any external source. Note that the typing annotation is required to be ClassVar for the ExternalSourceConfig attribute, so that it will not be considered as a field of the settings class. Currently, the ExternalSourceConfig supports to speacify a validation_alias to override the name of setting field, and a default_value to provide a default value when the settings field is not found both in the external source and the inner source(like .env file and environment variables).

To use a specific external usage, like database, you can create a subclass of ExternalSourceConfig and provide a callable to the __init__ method, which will be called to get the value of the settings field. Note that if the field setting is not found in the external source, the callable should return None, so that the default value can be used.