New Resource: azurerm_kubernetes_cluster_node_pool

Co-authored-by: titilambert <titilambert@ttb.lt>
Co-authored-by: djsly <sylvain.boily@gmail.com>

This commit rebases @titilambert's original commits on top of #4898
In addition it also makes a couple of changes:

- The resource has been renamed `azurerm_kubernetes_cluster_node_pool` to match
  the latest terminology used in the Portal
- The tests have been updated to use a Default Node Pool block in the AKS resource
- During creation we now check for the presence of the parent Cluster and then
  confirm that the Default Node Pool is a VirtualMachineScaleSet type
- Removes support for `orchestrator_version` temporarily - since this wants to be
  added to both the Default Node Pool and this resource at the same time/in the same PR
  since this wants some more specific tests (which'd be easier to review in a separate PR)
- Matches the name/schema for all fields with the `default_node_pool` block in the AKS resource

I've ended up `git reset HEAD~N` here to work around the merge conflict due to the large changes
within the AKS resource in #4898, but this seemed like the most pragmatic way to ship these changes.

azurerm/internal/services/containers/nodepool_id.go

@@ -0,0 +1,45 @@
+package containers
+
+import (
+	"fmt"
+
+	"github.com/terraform-providers/terraform-provider-azurerm/azurerm/helpers/azure"
+)
+
+type KubernetesNodePoolID struct {
+	Name          string
+	ClusterName   string
+	ResourceGroup string
+
+	ID azure.ResourceID
+}
+
+func ParseKubernetesNodePoolID(id string) (*KubernetesNodePoolID, error) {
+	clusterId, err := azure.ParseAzureResourceID(id)
+	if err != nil {
+		return nil, err
+	}
+
+	resourceGroup := clusterId.ResourceGroup
+	if resourceGroup == "" {
+		return nil, fmt.Errorf("%q is missing a Resource Group", id)
+	}
+
+	clusterName := clusterId.Path["managedClusters"]
+	if clusterName == "" {
+		return nil, fmt.Errorf("%q is missing the `managedClusters` segment", id)
+	}
+
+	nodePoolName := clusterId.Path["agentPools"]
+	if nodePoolName == "" {
+		return nil, fmt.Errorf("%q is missing the `agentPools` segment", id)
+	}
+
+	output := KubernetesNodePoolID{
+		Name:          nodePoolName,
+		ClusterName:   clusterName,
+		ResourceGroup: resourceGroup,
+		ID:            *clusterId,
+	}
+	return &output, nil
+}

azurerm/provider.go

@@ -313,6 +313,7 @@ func Provider() terraform.ResourceProvider {
 		"azurerm_key_vault_secret":                                   resourceArmKeyVaultSecret(),
 		"azurerm_key_vault":                                          resourceArmKeyVault(),
 		"azurerm_kubernetes_cluster":                                 resourceArmKubernetesCluster(),
+		"azurerm_kubernetes_cluster_node_pool":                       resourceArmKubernetesClusterNodePool(),
 		"azurerm_kusto_cluster":                                      resourceArmKustoCluster(),
 		"azurerm_kusto_database":                                     resourceArmKustoDatabase(),
 		"azurerm_kusto_eventhub_data_connection":                     resourceArmKustoEventHubDataConnection(),