[BUG] runtime error: index out of range [0] with length 0

[NMamont]

Describe the bug

I've already created a node pool, with only annotations in template attributes. After upgrading the provider from 0.27 to 0.30 version, I faced that for this node pool tf tried to update each time the template block, so I decided to add labels also, to avoid these trash messages.

  ~ resource "ovh_cloud_project_kube_nodepool" "this" {
        id               = "xxx"
        name             = "nodepool-xxx"
        # (18 unchanged attributes hidden)

      - template {
          - metadata {
              - annotations = {
                  - "class" = "general"
                  - "type"  = "infra-nodes"
                } -> null
              - finalizers  = [] -> null
              - labels      = {} -> null
            }
        }
      + template {
          + metadata {
              + annotations = {
                  + "class" = "general"
                  + "type"  = "infra-nodes"
                }
              + finalizers  = []
            }

          + spec {
              + taints        = []
              + unschedulable = false
            }
        }
    }
      - template {
          - metadata {
              - annotations = {
                  - "class" = "general"
                  - "type"  = "infra-nodes"
                } -> null
              - finalizers  = [] -> null
              - labels      = {} -> null
            }
        }
    }

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

But after adding labels, the provider was crushed with panic.

Terraform Version

Run terraform -v to show the version. If you are not running the latest version of Terraform, please upgrade because your issue may have already been fixed.

OVH Terraform Provider Version

terraform -v
Terraform v1.2.9
on darwin_amd64
+ provider registry.terraform.io/ovh/ovh v0.30.0

Your version of Terraform is out of date! The latest version
is 1.4.6. You can update by downloading from https://www.terraform.io/downloads.html

Affected Resource(s)

Please list the resources as a list, for example:

• ovh_cloud_project_kube_nodepool

If this issue appears to affect multiple resources, it may be an issue with Terraform's core.

Terraform Configuration Files

resource "ovh_cloud_project_kube_nodepool" "this" {
  service_name  = var.service_name
  kube_id       = ovh_cloud_project_kube.mycluster.id
  for_each      = { for k, v in local.node_pools : k => v }
  autoscale     = lookup(each.value, "autoscale", var.node_pool_default["autoscale"])
  name          = lookup(each.value, "name", var.node_pool_default["autoscale"])
  flavor_name   = lookup(each.value, "flavor_name", var.node_pool_default["flavor_name"])
  desired_nodes = lookup(each.value, "desired_nodes", var.node_pool_default["desired_nodes"])
  max_nodes     = lookup(each.value, "max_nodes", var.node_pool_default["max_nodes"])
  min_nodes     = lookup(each.value, "min_nodes", var.node_pool_default["min_nodes"])
  template {
    metadata {
      annotations = lookup(each.value, "annotations", var.node_pool_default["annotations"])
      labels      = lookup(each.value, "labels", var.node_pool_default["labels"])
    }
    spec {
      taints = lookup(each.value, "taints", var.node_pool_default["taints"])
      unschedulable = lookup(each.value, "unschedulable", var.node_pool_default["unschedulable"])
    }
  }
}


locals {
  node_pools = [
    {
      autoscale     = true
      name          = "xxx"
      flavor_name   = "b2-7"
      desired_nodes = 4
      max_nodes     = 7
      min_nodes     = 4
      annotations = {
        type  = "infra-nodes"
        class = "general"
      }
      labels = {
        type  = "infra-nodes"
        class = "general"
      }
    }
    ]
    
 variable "node_pool_default" {
  type = any
  default = {
    name          = "default-node-pool"
    flavor_name   = "d2-8"
    autoscale     = true
    desired_nodes = 1
    max_nodes     = 2
    min_nodes     = 1
    annotations   = {}
    labels        = {}
    taints        = []
    unschedulable = false
  }
}

Debug Output

Please provider a link to a GitHub Gist containing the complete debug output: https://www.terraform.io/docs/internals/debugging.html. Please do NOT paste the debug output in the issue; just paste a link to the Gist.
https://gist.github.com/NMamont/ab2669bfe26d529d7f7d164e04cd4fa2

Panic Output

If Terraform produced a panic, please provide a link to a GitHub Gist containing the output of the crash.log.

Expected Behavior

Terraform should update labels field for nodepool

Terraform will perform the following actions:

  # ovh_cloud_project_kube_nodepool.this["0"] will be updated in-place
  ~ resource "ovh_cloud_project_kube_nodepool" "this" {
        id               = "xxx"
        name             = "nodepool-xxx"
        # (18 unchanged attributes hidden)

      + template {
          + metadata {
              + annotations = {
                  + "class" = "general"
                  + "type"  = "infra-nodes"
                }
              + finalizers  = []
              + labels      = {
                  + "class" = "general"
                  + "type"  = "infra-nodes"
                }
            }

          + spec {
              + taints        = []
              + unschedulable = false
            }
        }
      - template {
          - metadata {
              - annotations = {
                  - "class" = "general"
                  - "type"  = "infra-nodes"
                } -> null
              - finalizers  = [] -> null
              - labels      = {} -> null
            }
        }
    }

Actual Behavior

Terraform crashed on update operation

Steps to Reproduce

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

1. terraform apply

References

Additional context

[yomovh]

Thanks for your issue. I have redirected it to the appropriate team.