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Testing

Disabling Cache for Testing

By default, the modeler uses cache - the parsed model is cached for performance improvement for multiple 'get' calls.

In some cases, such as during testing, you may want to turn off the cache. You can do this by setting the LAMBDA_ENV_MODELER_DISABLE_CACHE environment variable to true.

This is especially useful in tests where each test sets a different set of environment variables for the same model.

Here's an example of how you can use this in a pytest test:

pytest.py
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import json
from http import HTTPStatus
from typing import Any, Dict, Literal
from unittest.mock import patch

from pydantic import BaseModel

from aws_lambda_env_modeler import LAMBDA_ENV_MODELER_DISABLE_CACHE, get_environment_variables, init_environment_variables


class MyHandlerEnvVars(BaseModel):
    LOG_LEVEL: Literal['DEBUG', 'INFO', 'ERROR', 'CRITICAL', 'WARNING', 'EXCEPTION']


@init_environment_variables(model=MyHandlerEnvVars)
def my_handler(event: Dict[str, Any], context) -> Dict[str, Any]:
    env_vars = get_environment_variables(model=MyHandlerEnvVars)  # noqa: F841
    # can access directly env_vars.LOG_LEVEL as dataclass
    return {
        'statusCode': HTTPStatus.OK,
        'headers': {'Content-Type': 'application/json'},
        'body': json.dumps({'message': 'success'}),
    }


@patch.dict('os.environ', {LAMBDA_ENV_MODELER_DISABLE_CACHE: 'true', 'LOG_LEVEL': 'DEBUG'})
def test_my_handler():
    response = my_handler({}, None)
    assert response['statusCode'] == HTTPStatus.OK
    assert response['headers'] == {'Content-Type': 'application/json'}
    assert json.loads(response['body']) == {'message': 'success'}