fix: lookup default value for soft delete policy

[alexandre-abrioux]

This fix is a follow up to #309

Issue

On a multi-bucket configuration, adding a soft_delete_policy configuration block like so:

  soft_delete_policy = {
    "bucket1" = {
      // Disable protection on this bucket
      retention_duration_seconds = 0
    }
    "bucket2" = {
      // Increase protection to the max value (90 days)
      retention_duration_seconds = 7776000
    }
  }

; results in the following error:

│ Error: Invalid function argument
│ 
│   on .terraform/modules/gcs.cloud_storage/main.tf line 160, in resource "google_storage_bucket" "buckets":
│  160:     for_each = [lookup(var.soft_delete_policy, each.value, {})]
│     ├────────────────
│     │ while calling lookup(inputMap, key, default...)
│ 
│ Invalid value for "default" parameter: the default value must have the same
│ type as the map elements.

Fix

Instead of using an empty object {} as the default value of the lookup, we need to specify a complete object with every default value. The issue of not being able to use an empty object is described here: hashicorp/terraform#35027

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[alexandre-abrioux]

Hi @bharathkkb, maybe you could review this one? It's a fix related to your previous approval of #309. Thanks a lot 🙏

[jonathan-anyword]

Any update on this PR? need it also :)

[vdcadena553]

any updates here?

[flecno]

Would be great if this is fixed. As GCP will start billing the soft delete in September I really want to disable it for some buckets, created by this module.

[alexandre-abrioux]

Maybe @apeabody could help run CI and approve?

[apeabody]

/gcbrun

[apeabody]

Thanks for the contribution @alexandre-abrioux!