[HOWTO] Get Azure Function key and set it as value of a not managed key vault secret using Terraform and AzAPI provider

data "azurerm_key_vault" "kv" {
  name                = "KV_NAME_HERE"
  resource_group_name = "RG_NAME_HERE"
}
resource "azapi_resource_action" "azure_function_listkeys" {
  type        = "Microsoft.Web/sites/functions@2026-03-15"
  resource_id = "${azurerm_function_app_flex_consumption.example_app.id}/functions/ExampleFunction"
  action      = "listkeys"
  method      = "POST"
  response_export_values = ["*"]
  when = "apply"
}
resource "azapi_resource_action" "set_keyvault_secret_value_with_function_key" {
  type        = "Microsoft.KeyVault/vaults/secrets@2026-03-01-preview"
  resource_id = "${data.azurerm_key_vault.kv.id}/secrets/arbitrary-secret"
  method      = "PUT"
  body = {
    properties = {
      value = try(
        jsondecode(azapi_resource_action.azure_function_listkeys.output).default,
        azapi_resource_action.azure_function_listkeys.output.default
      )
    }
  }
  when = "apply"
}