https://dagster.io/ logo
#ask-ai
Title
# ask-ai
m

Mikael Frosthage

02/07/2024, 8:24 AM
is it good practise testing the created defs variable. You know from variable Definititions creates in init.py generates
s

Scout

02/07/2024, 8:24 AM
Testing the
defs
variable, which is an instance of
Definitions
created in
__init__.py
, can be considered a good practice, especially when you want to ensure that your Dagster assets and resources are configured correctly. Testing can help catch issues early in the development process and can be crucial for maintaining code quality and reliability. The documentation provides examples of how to test various components in Dagster, such as assets and resources. For instance, you can use the
build_init_resource_context
function to build an
InitResourceContext
outside of execution, which is intended to be used when testing a resource. This allows you to initialize and test resources in isolation without having to run a full Dagster job. Here's an example from the documentation that shows how to test an asset that uses both configuration and a resource:
Copy code
python class MyConfig(Config):     api_url: str  class MyAPIResource(ConfigurableResource):     def query(self, url) -> Dict[str, Any]:         return requests.get(url).json()  @asset def uses_config_and_resource(config: MyConfig, my_api: MyAPIResource):     return my_api.query(config.api_url)  def test_uses_resource() -> None:     result = uses_config_and_resource(         config=MyConfig(api_url="<https://dagster.io>"), my_api=MyAPIResource()     )     assert result == {"foo": "bar"}
In this example, the
uses_config_and_resource
asset is tested with a specific configuration and a mock resource. This kind of testing ensures that the asset behaves as expected when provided with certain inputs. Additionally, the documentation mentions the use of environment variables for managing sensitive information and configuration, which can be important for testing as well. By using environment variables, you can avoid hardcoding sensitive information and make your tests more flexible and secure. In summary, testing the
defs
variable and the components it contains is a good practice in Dagster, and the documentation provides guidance on how to perform these tests effectively.