Openstack volume does not detect detach

[GiovanniPaoloGibilisco]

Descirption

After creating an image with a root volume and an additional volume attached if the terraform configuration file is changed to remove the attachment (the volume object in the openstack_compute_instance_v2 resource) the terraform plan command does not detect the change

Terraform Version

$ terraform -v
Terraform v0.7.0

Affected Resource(s)

The issue affects these resources:

• openstack_blockstorage_volume_v1
• openstack_compute_instance_v2

Terraform Configuration Files

This issue occurs after modifying the configuration file. The initial file is the following

resource "openstack_blockstorage_volume_v1" "root_volume_1" {
  name = "root_volume_1"
  size = 10
  image_id = "90ee49d8-1c18-45ca-8a72-14ffd120521e"
}

resource "openstack_blockstorage_volume_v1" "additional_volume_1" {
  name = "additional_volume_1"
  size = 5
}

resource "openstack_compute_instance_v2" "test_name" {
  name = "test_name"
  flavor_id = "3"
  key_pair = "test-keypair"
  security_groups = ["default"]

  block_device {
    uuid = "${openstack_blockstorage_volume_v1.root_volume_1.id}"
    source_type = "volume"
    boot_index = 0
    destination_type = "volume"
    delete_on_termination = false
  }

  volume {
    volume_id = "${openstack_blockstorage_volume_v1.additional_volume_1.id}"
  }

  metadata {
    application = "app1"
  }

  network {
    name = "network"
  }
}

After applying this configuration remove the volume object in the vm and you get the following file

resource "openstack_blockstorage_volume_v1" "root_volume_1" {
  name = "root_volume_1"
  size = 10
  image_id = "90ee49d8-1c18-45ca-8a72-14ffd120521e"
}

resource "openstack_blockstorage_volume_v1" "additional_volume_1" {
  name = "additional_volume_1"
  size = 5
}

resource "openstack_compute_instance_v2" "test_name" {
  name = "test_name"
  flavor_id = "3"
  key_pair = "test-keypair"
  security_groups = ["default"]

  block_device {
    uuid = "${openstack_blockstorage_volume_v1.root_volume_1.id}"
    source_type = "volume"
    boot_index = 0
    destination_type = "volume"
    delete_on_termination = false
  }

  metadata {
    application = "app1"
  }

  network {
    name = "network"
  }
}

Debug Output

The debug output is in this gist

Expected Behavior

The terraform plan command should detech the need to detach the openstack_blockstorage_volume_v1.additional_volume_1

Actual Behavior

The terraform plan command did not detect any changes

Steps to Reproduce

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

1. create a config.tf file as reported above
2. terraform apply
3. modify the config.tf file removing the volume element from the vm (see above)
4. terraform plan

References

No known issues

[GiovanniPaoloGibilisco]

Added pull request #8101 for including acceptance test to reproduce the issue

[ghost]

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