Fix the gcp_gcs_delete_objects operator delete whole bucket on processing empty list of objects

[yupbank]

currently the GCSDeleteObjectsOperator operator will delete the whole bucket when accepting an empty list of objects. which is a bug. It should quietly skip when processing an empty list.

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[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

[RemyOstyn]

Hello @yupbank,

I found the same issue when using Airflow Task Group. If we forget to specify the when pulling files paths from xcoms, the objects will be an empty array between double quotes "[]" and the GCSDeleteObjectsOperator will delete the whole bucket content.

Example: (let's assume these tasks are in a task group)

list_files_from_gcs = GCSListObjectsOperator(
            task_id="list_files_from_gcs",
            bucket="my-bucket",
            match_glob=path + "/*.csv",
        )

remove_files_from_gcs = GCSDeleteObjectsOperator(
            task_id="remove_files_from_gcs",
            bucket_name="my-bucket,
            objects="{{ ti.xcom_pull('list_files_from_gcs') }}",
        )

Instead of:

list_files_from_gcs = GCSListObjectsOperator(
            task_id="list_files_from_gcs",
            bucket="my-bucket",
            match_glob=path + "/*.csv",
        )

remove_files_from_gcs = GCSDeleteObjectsOperator(
            task_id="remove_files_from_gcs",
            bucket_name="my-bucket",
            objects="{{ ti.xcom_pull('my_task_group.list_files_from_gcs') }}", // As you can see I have to specify the task group here to avoid deleting the whole bucket
        )

Is there a way to add protection when using task group?