Terraform: How to create dynamic default_action in aws_lb_listener

Question

I create ALBs based on a JSON file where I have a variable public which can be yes or no.

As below:

[
    {
        "service-name": "test1",
        "public"         : "yes"
    },
    {
        "service-name": "test2",
        "public"         : "no"
    }
]

I then use this JSON to create ALBs, with the snippet below, which works fine.

resource "aws_lb_listener" "lb_listener" {
    count             = length(var.services)
    load_balancer_arn = aws_lb.some_alb[count.index].arn
    port              = 80
    protocol          = "HTTP"
    
    default_action {
      target_group_arn = aws_lb_target_group.some_target[count.index].arn
      type             = "forward"
    }
}

What I am after is to have a dynamic default_action based on the public variable. I want it to redirect to HTTPS when public==yes and forward to the target_group when public==no.

I tried this:

resource "aws_lb_listener" "lb_listener" {
    count             = length(var.services)
    load_balancer_arn = aws_lb.some-alb[count.index].arn
    port              = 80
    protocol          = "HTTP"

    //Public ALB redirects to port 443
    dynamic "default_action" {
      for_each = [
        for i in var.services : i
        if var.services[i].public == "yes"
      ]

      type = "redirect"

      redirect {
        port        = "443"
        protocol    = "HTTPS"
        status_code = "HTTP_301"
      }
    }

    //Private just forwards to the target group
    dynamic "default_action" {
      for_each = [
        for i in var.services : i
        if var.services[i].public == "no"
      ]

      default_action {
        target_group_arn = aws_lb_target_group.some_target[count.index].arn
        type             = "forward"
      }
    }
}

But I got the error:

At least 1 "default_action" blocks are required.
Blocks of type "redirect" are not expected here.

Will appreciate your help. Thanks!

Answer 1

Based on the comments:

Instead of default_action, it should be content.