Setting automatic_channel_upgrade to "patch" leads to Terraform state drift

[zioproto]

Is there an existing issue for this?

• I have searched the existing issues

Greenfield/Brownfield provisioning

greenfield

Terraform Version

1.4.2

Module Version

6.7.1

AzureRM Provider Version

v3.49.0

Affected Resource(s)/Data Source(s)

azurerm_kubernetes_cluster

Terraform Configuration Files

module "aks" {
  source                           = "Azure/aks/azurerm"
  version                          = "6.7.1"
  kubernetes_version               = "1.25"
  orchestrator_version             = null
  automatic_channel_upgrade        = "patch"
[..CUT..]
}

tfvars variables values

none

Debug Output/Panic Output

~ resource "azurerm_kubernetes_cluster" "main" {
id = "{REDACTED}"
~ kubernetes_version = "1.25.6" -> "1.25"

Expected Behaviour

Terraform should not have state drift when an automatic upgrade happens in the patch channel.

Actual Behaviour

When creating the cluster the AKS API returns this values:

 az aks show --name istio-aks -g istio-aks -o json | jq ".kubernetesVersion, .currentKubernetesVersion"
"1.25"
"1.25.5"

After an automatic upgrade ( automatic_channel_upgrade=patch ) the AKS API will return something like:

 az aks show --name istio-aks -g istio-aks -o json | jq ".kubernetesVersion, .currentKubernetesVersion"
"1.25.6"
"1.25.6"

Because Terraform saved in the state:

   "kubernetes_version": "1.25",

This will cause a Terraform state drift at the next terraform apply operation.

Steps to Reproduce

terraform apply with this minimal config:

module "aks" {
  source                           = "Azure/aks/azurerm"
  version                          = "6.7.1"
  kubernetes_version               = "1.25"
  orchestrator_version             = null
  automatic_channel_upgrade        = "patch"
[..CUT..]
}

Wait for an automatic upgrade to happen and run again terraform apply

Important Factoids

No response

References

No response