google_compute_route forces new resource for next_hop_instance

[hashibot]

This issue was originally opened by @mwallman as hashicorp/terraform#16508. It was migrated here as a result of the provider split. The original body of the issue is below.

---

Terraform Version

Terraform v0.10.8

Terraform Configuration Files

resource "google_compute_route" "route" {
  name = "${var.name}-route"
  network = "${var.network}"
  dest_range = "0.0.0.0/0"
  priority = "${var.priority}"
  next_hop_instance = "${google_compute_instance.nat.self_link}"
  next_hop_instance_zone = "${var.zone}"
  tags = "${var.route_tags}"
}

Expected Behavior

Nothing, because nothing changed.

Actual Behavior

Terraform will perform the following actions:

  + google_compute_route.route
      id:                     <computed>
      dest_range:             "0.0.0.0/0"
      name:                   "us-west1-a-nat-route"
      network:                "https://www.googleapis.com/compute/v1/projects/marketo-network-dev/global/networks/dev-vpc"
      next_hop_instance:      "https://www.googleapis.com/compute/v1/projects/marketo-network-dev/zones/us-west1-a/instances/us-west1-a-nat"
      next_hop_instance_zone: "us-west1-a"
      next_hop_network:       <computed>
      priority:               "800"
      self_link:              <computed>
      tags.#:                 "1"
      tags.1668485976:        "us-west1-nat-external"

  - module.us-west1-a-nat.google_compute_route.route


Plan: 1 to add, 0 to change, 1 to destroy.

**It recreates the instance, and hence the route, on each apply

Steps to Reproduce

Please list the full steps required to reproduce the issue, for example:

1. terraform plan

[rosbo]

Hi @mwallman,

I opened a PR to fix this issue.

As a workaround, you can update your config to use the instance name instead of the self_link.

Your configuration would look like this:

resource "google_compute_route" "route" {
  name = "${var.name}-route"
  network = "${var.network}"
  dest_range = "0.0.0.0/0"
  priority = "${var.priority}"
  next_hop_instance = "${google_compute_instance.nat.name}"
  next_hop_instance_zone = "${var.zone}"
  tags = "${var.route_tags}"
}

My fix (#716) will allow users to use the instance name or the instance self_link in the next_hop_instance field.

[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 👉 hashibot-feedback@hashicorp.com. Thanks!