Added 'custom_args' attribute to AbstractDataset class

[noamgoldberg]

Description

The Inspiration

• In my experience with Kedro, perhaps one of the most useful CI/CD methods is selecting which artifacts (datasets) to save to experiment-specific folders (and which to avoid saving repeatedly, such as large training datasets).
• The best method I have found to accomplish this is through the creation of an AbstractDataset, to accept 'custom_args'.
  • For example, I could create project_name.custom_datasets.csv.CustomCSVDataset and write the following catalog.yml:

    predictions:
        type: project_name.custom_datasets.csv.CustomCSVDataset
        filepath: data/08_reporting/predictions.csv
        custom_args:
            save_to_mlruns: True
    

  • I could then configure my code to dynamically save this dataset to mlruns/08_reporting/predictions.csv (and, similarly, do so for all datasets with save_to_mlruns: True in the catalog).

Personally, this is my most frequent (and favorite) application of "dataset-specific" args. Unfortunately, I find myself creating a custom class for each type of artifact (i.e. CSV, plotly, pickle, etc.), and do so again each time I create a new kedro project.

Broader Usage

The above is a very specific use of the proposed 'custom_args' feature, though I believe many developers would find it useful to have access to custom args without having to rewrite numerous custom classes. I know it was a popular feature among my former team members (for the dynamic saving method detailed above)!

Development notes

Given the minor extent of the change, I don't believe this merits an independent test. If I were to test it, however, I would test the instantiation of an AbstractDataset, a child of AbstractDataset (i.e. CSVDataSet), and ensure I could properly access the configured custom_args.

Developer Certificate of Origin

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Checklist

• [ ] Read the contributing guidelines
• [ ] Signed off each commit with a Developer Certificate of Origin (DCO)
• [ ] Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• [ ] Updated the documentation to reflect the code changes
• [ ] Added a description of this change in the RELEASE.md file
• [ ] Added tests to cover my changes
• [ ] Checked if this change will affect Kedro-Viz, and if so, communicated that with the Viz team

[astrojuanlu]

Hi @noamgoldberg , thanks for your PR!

Before proceeding, could you have a look at the metadata key and see if it would suit your needs? It's not part of the AbstractDataset, but all derived datasets have it.

[astrojuanlu]

Hi @noamgoldberg , I echo what I said about metadata in https://github.com/kedro-org/kedro/pull/3737#issuecomment-2095343920

About custom arguments, the preferred route would be to either use metadata or define your own dataset.

I appreciate your pull request but I am closing it for now 🙏🏼 If you have further ideas on how to improve Kedro, please open a new Discussion in the "Discussions" tab and let's take it from there.

Thanks again!