google_compute_subnetwork resource - support an expansion of CIDR range

[hashibot]

This issue was originally opened by @Dnefedkin as hashicorp/terraform#11689. It was migrated here as part of the provider split. The original body of the issue is below.

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Terraform Version

0.8.5

Affected Resource(s)

• google_compute_subnetwork

Changing ip_cidr_range argument of google_compute_subnetwork resource leads to recreation of the subnetwork object, the update method is not implemented.

GCE API has a method Subnetworks: expandIpCidrRange [1] that allows to modify the existing subnetwork and change a CIDR range in case if a new CIDR range is a superset of the range previously defined before the update.

The proposal is to modify google_compute_subnetwork resource by adding code allowing to expand a CIDR range. It's not clear to me how resource should behave in a new CIDR range is not a superset of an old one.

[1] - https://cloud.google.com/compute/docs/reference/latest/subnetworks/expandIpCidrRange

[rosbo]

Note to the implementer:

We can use the new helper customdiff, to make the ip_cidr_range ForceNew only if the change narrows down the range.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. If you feel I made an error 🤖 🙉 , please reach out to my human friends 👉 [email protected]. Thanks!