What is the difference between using

ins

and

deps

in the asset decorator?

In the context of Dagster's asset decorator,

ins

and

deps

serve different purposes for defining dependencies between assets. - `ins`: This parameter is used to define input dependencies for an asset. When you specify

ins

, you are indicating that the asset takes data from another asset as an input. This creates a direct data dependency where the output of one asset is used as the input for another. The

ins

parameter expects a dictionary where the keys are the names of the input parameters of the asset function and the values are instances of

AssetIn

, which can specify the key of the upstream asset. - `deps`: This parameter is used to define dependencies that do not correspond to a direct data input to the asset. It allows you to specify upstream assets that the current asset depends on, without those assets passing data directly into it. This can be useful for cases where the execution of an asset should be triggered by the materialization of another asset, but no data is passed between them. The

deps

parameter is a more recent addition to the asset decorator and is meant to replace the now-deprecated

non_argument_deps

parameter, which served a similar purpose. The

deps

parameter accepts a list of assets, which allows for better type checking and error detection during development. Here's an example from the documentation illustrating the use of `deps`:

python
@asset(deps=[iris_dataset])
def iris_setosa(duckdb: DuckDBResource) -> None:
    with duckdb.get_connection() as conn:
        conn.execute(
            "CREATE TABLE iris.iris_setosa AS"
            " SELECT * FROM iris.iris_dataset"
            " WHERE species = 'Iris-setosa'"
        )

In this example,

iris_setosa

is an asset that depends on the

iris_dataset

asset. The

deps

parameter is used to declare this dependency, even though

iris_setosa

does not take

iris_dataset

as a direct input. It's important to note that the

deps

parameter is part of Dagster's ongoing efforts to improve the asset model, and it is recommended to use

deps

over

non_argument_deps

for defining non-data dependencies between assets. add

deps

parameter to @graph_asset and... button Assets vs Ops button The future of I/O managers: an opt-in la... button Different concepts to define an asset button Thank you for your feedback!

@Scout Where does

AssetDep

come into play?

AssetDep

is not a term that is directly referenced in the documentation provided. It's possible that

AssetDep

could be a term used in a different context or in earlier versions of Dagster, or it might be a misunderstanding or typo related to

AssetIn

or

deps

. In the context of defining dependencies between assets in Dagster, you would use

AssetIn

to specify the key of an upstream asset when defining input dependencies using the

ins

parameter, and you would use

deps

to specify dependencies that do not correspond to direct data inputs. If you are looking for information on how to define dependencies between assets, you should use the

ins

parameter with

AssetIn

for input dependencies and the

deps

parameter for non-data dependencies, as described in the previous messages. If

AssetDep

is something specific to your codebase or a plugin you are using, or if it's a term from an older version of Dagster that has since been updated, I would recommend checking the relevant code or documentation for that specific context. If you have more information or a different context where

AssetDep

is used, please provide additional details, and I'll do my best to assist you further.