issue #28 - RegionInstanceGroupManager is forced to be re-created - fix.

[pksmall]

Fixes #28

Highlight:

~ distribution_policy_zones = [
          - "europe-west3-a",
          - "europe-west3-b",
          - "europe-west3-c",
        ] -> (known after apply) # forces replacement

ignore using lifecycle

[morgante]

@pksmall I'm not sure this is a sufficient fix, as it would prevent people from updating the desired zones of a MIG after creating it.

[pksmall]

@morgante Agree, but this will have to change:

  lifecycle {
    create_before_destroy = "true"
  }

to false

I added to a test project distribution_policy_zones by groups and got same error.

[morgante]

I'm still unclear what is happening here though.

Without this, is Terraform claiming that the distribution zones have changed with every apply (even when they are untouched)?

[pksmall]

@morgante Exactly,

data "google_compute_zones" "available" {
  project = var.project_id
}

this definition is not constant for Terraform. Every apply Terraform overwrites a new.

[morgante]

Got it, thanks. This does seem like the only workable fix unfortunately.

Could you add a note to the README and CHANGELOG that you will have to force recreation yourself if you want to change distribution zones?

[pksmall]

@morgante sure.

If you accept this fix, it would be nice to remove the unnecessary code from the module.