Local Mode

Local is a mode for settings configurators that use an external service to get a configuration data and in local development it is more convenient to use a switch to a different provider and with the same set of fields.

Here I will give an example of using local mode in VaultKVSettings.

Let's say we have the following configuration:

import hvac

from pydantic import Field, BaseModel

from sitri.settings.contrib.vault import VaultKVSettings
from sitri.providers.contrib.vault import VaultKVConfigProvider
from sitri.providers.contrib.system import SystemConfigProvider

configurator = SystemConfigProvider(prefix="superapp")
ENV = configurator.get("env")


def vault_client_factory() -> hvac.Client:
    client = hvac.Client(url=configurator.get("vault_api"))

    client.auth_approle(
        role_id=configurator.get("role_id"),
        secret_id=configurator.get("secret_id"),
    )

    return client


provider = VaultKVConfigProvider(
    vault_connector=vault_client_factory, mount_point=f"superapp/{ENV}"
)


class DBSettings(VaultKVSettings):
    url: str = Field(...)
    name: str = Field(...)

    class Config:
        provider = provider
        default_secret_path = "db"

And in a local-development environment, we don't want to deploy Vault, then we can use regular json, for example in file config.json:

{
  "db": {
    "url": "psql://localhost",
    "name": "testdb"
  }
}

Next, we just need to add the class of our settings to the config, the fields necessary to use the local mode:

is_local_mode = ENV == "local"
local_mode_filepath = configurator.get(
    "local_mode_file_path"
)  # export SUPERAPP_LOCAL_MODE_FILE_PATH=/path/to/config.json


class BaseSettingsConfig(VaultKVSettings.VaultKVSettingsConfig):
    provider = provider

    local_mode = is_local_mode
    local_mode = local_mode
    local_provider_args = {"json_path": local_mode_filepath}


class DBSettings(VaultKVSettings):
    url: str = Field(...)
    name: str = Field(...)

    class Config(BaseSettingsConfig):
        default_secret_path = "db"
        local_mode_path_prefix = "db"

If local_mode=True, then DBSettings lookup to json file and collect config data from it.