import os


def config_from_environ(app, prefix=None):
    if not prefix:
        prefix = app.config.get('APP_NAME')

    for name, value in os.environ.items():
        if name.startswith(prefix):
            if isinstance(value, str):
                value = value.strip()

            if value:
                app.config[name[len(prefix) + 1:]] = value


class BaseConfig:
    JWT_TOKEN_LOCATION = 'json'
    JWT_IDENTITY_CLAIM = 'sub'