`upcloud_loadbalancer` individual nodes not accessible in output

[avaly]

Using upcloud_loadbalancer with public & private networks, the output of the public IP address can't be read in an output field:

resource "upcloud_network" "lb_network" {
  ...
}
resource "upcloud_loadbalancer" "lb" {
  name = "lb-test"
  plan = "development"
  zone = var.lb_zone
  networks {
    name   = "Public-Net"
    type   = "public"
    family = "IPv4"
  }
  networks {
    name    = "Private-Net"
    type    = "private"
    family  = "IPv4"
    network = resource.upcloud_network.lb_network.id
  }
}
output "load_balancer_ip_public" {
  value = upcloud_loadbalancer.lb.nodes[0].networks[0].ip_addresses[0].address
}

Throws the following error by Terraform:

│ Error: Invalid index
│ 
│   on cluster.tf line 161, in output "load_balancer_ip_public":
│  161:   value = upcloud_loadbalancer.lb.nodes[0].networks[0].ip_addresses[0].address
│ 
│ This value does not have any indices.

But changing the value of the output to just upcloud_loadbalancer.lb.nodes, prints the following plan:

Changes to Outputs:
  + load_balancer_ip_public = [
      + {
          + networks          = [
              + {
                  + ip_addresses = [
                      + {
                          + address = "REDACTED"
                          + listen  = true
                        },
                    ]
                  + name         = "Public-Net"
                  + type         = "public"
                },
              + {
                  + ip_addresses = [
                      + {
                          + address = "10.0.0.3"
                          + listen  = false
                        },
                      + {
                          + address = "10.0.0.4"
                          + listen  = true
                        },
                    ]
                  + name         = "Private-Net"
                  + type         = "private"
                },
            ]
          + operational_state = "running"
        },
    ]

So it seems to be a list of records. But as soon as we add [0] after the .nodes, we get:

│ Error: Invalid index
│ 
│   on cluster.tf line 161, in output "load_balancer_ip_public":
│  161:   value = upcloud_loadbalancer.main.nodes[0]
│ 
│ This value does not have any indices.

I'm using the v5.22.1 version of the provider.

[kangasta]

Hello! Thank you for the bug report and sorry for the delay with this. There is at least issue in the provider logic with setting the nodes value on initial apply as we have not waited for the load balancer to be in running state and thus the nodes list has not been available when we set the state. #791 should help with that part of the problem.

The error could happen because nodes is empty after the initial apply and the output expression seems to be validated with current value before running the apply. You could try to run apply with the output value set to upcloud_loadbalancer.lb.nodes to refresh the state and then try to apply again with the value set to the complete expression (upcloud_loadbalancer.lb.nodes[0].networks[0].ip_addresses[0].address).