terraform detects in-place update: metadata is always set to null

[yildizbilal]

Current Behaviour
Upgraded from 7.12.2 to 7.16.2. We are deploying 5 watchers to kibana with the provider and just one of them uses the metadata flag. For the other 4 terraform tries to set the metadata value to null.

Expected Behaviour
Terraform shouldn't detect any updatable attributes and should show no changes detected.

Terraform Configuration

resource "elasticsearch_watcher" "alert" {
  name            = var.NAME
  trigger         = jsonencode(local.template.trigger)
  input           = jsonencode(local.template.input)
  condition       = jsonencode(local.template.condition)
  actions         = jsonencode(local.template.actions)
  metadata        = jsonencode(try(local.template.metadata, null))
  throttle_period = try(local.template.throttle_period, null)

  lifecycle {
    ignore_changes = [
      throttle_period
    ]
  }
}

Plan Output

[...]  

# module.watchers["redis-send-event-failed"].elasticsearch_watcher.alert will be updated in-place
  ~ resource "elasticsearch_watcher" "alert" {
        id        = "redis-send-event-failed"
      + metadata  = "null"
        name      = "redis-send-event-failed"
        # (4 unchanged attributes hidden)
    }

Plan: 0 to add, 4 to change, 0 to destroy.

Versions
Terraform: 1.2.3
disaster37/elasticsearch: 7.16.2

Workaround
Added metadata to the ignore_lifecycle lifecycle.

[disaster37]

Hi,

can you test with 8.4.0 release. If problem is still here, can you paste complete sample to reproduce it.
I can't play your sample because of I haven't your locals ...

Have a good day.