Pydantic AWS AppConfig

Ever wanted to use AWS AppConfig for your Python app, but can’t bear configs without pydantic?

Well, your days of using evil .env or .ini files, ENVIRONMENT variables or even custom providers is over!

With just a simple

pip install pydantic-appconfig

With a lot of inspiration from this AWS sample.

Introducing pydantic_appconfig.

1. Set yourself up with your favourite pydantic.BaseModel:

   class MyAppConfig(pydantic.BaseModel):
       """My app config."""
   
       test_field_string: str
       test_field_int: int
   
       class Config:
           """The pydantic config, including title for the JSON schema."""
   
           title = "MyAppConfig"

2. Set up the config helper using your shiny config class:

   from pydantic_appconfig import AppConfigHelper
   
   my_config: AppConfigHelper[MyAppConfig] = AppConfigHelper(
       appconfig_application="AppConfig-App",
       appconfig_environment="AppConfig-Env",
       appconfig_profile="AppConfig-Profile",
       max_config_age=15,
       fetch_on_init=True,
       config_schema_model=MyAppConfig,
   )

3. Use it:

   my_val = my_config.config.test_field_string

AWS AppConfig also has support for validators.

Pydantic is able to generate a JSON schema for you to upload:

print(MyAppConfig.schema_json(indent=2))

{
  "title": "MyAppConfig",
  "description": "My app config.",
  "type": "object",
  "properties": {
    "test_field_string": {
      "title": "Test Field String",
      "type": "string"
    },
    "test_field_int": {
      "title": "Test Field Int",
      "type": "integer"
    }
  },
  "required": [
    "test_field_string",
    "test_field_int"
  ]
}