fix: Changed default values for lambda_multi_value_headers_enabled and pro…

[nahuel242]

Description

Changed the default values for lambda_multi_value_headers_enabled and proxy_protocol_v2 from "null" to "default" in the "aws_lb_target_group" "main" resource

Motivation and Context

As mentioned by @antonbabenko in issue #156 , lambda_multi_value_headers_enabled and proxy_protocol_v2 are booleans so their default value should be also a boolean and not null.
This is also stated in the provider documentation:
https://www.terraform.io/docs/providers/aws/r/lb_target_group.html#proxy_protocol_v2
https://www.terraform.io/docs/providers/aws/r/lb_target_group.html#lambda_multi_value_headers_enabled

It's related to issue #156

Breaking Changes

No

How Has This Been Tested?

I've written a small test without specifying values for lambda_multi_value_headers_enabled and proxy_protocol_v2 and used as module source my forked branch with the fix

nahuelbatista@SSFF-00170 terraform-test % terraform plan -out=issue156.plan
Refreshing Terraform state in-memory prior to plan...
The refreshed state will be used to calculate this plan, but will not be
persisted to local or remote state storage.


------------------------------------------------------------------------

An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # module.alb.aws_lb.this[0] will be created
  + resource "aws_lb" "this" {
      + arn                        = (known after apply)
      + arn_suffix                 = (known after apply)
      + dns_name                   = (known after apply)
      + drop_invalid_header_fields = false
      + enable_deletion_protection = false
      + enable_http2               = true
      + id                         = (known after apply)
      + idle_timeout               = 60
      + internal                   = false
      + ip_address_type            = "ipv4"
      + load_balancer_type         = "application"
      + name                       = "my-alb"
      + security_groups            = [
          + "sg-033c46aea87a3d025",
        ]
      + subnets                    = [
          + "subnet-0b51932bf0e7664fa",
          + "subnet-0e22184d41bda1e94",
        ]
      + tags                       = {
          + "Environment" = "Test"
          + "Name"        = "my-alb"
        }
      + vpc_id                     = (known after apply)
      + zone_id                    = (known after apply)

      + subnet_mapping {
          + allocation_id = (known after apply)
          + subnet_id     = (known after apply)
        }

      + timeouts {
          + create = "10m"
          + delete = "10m"
          + update = "10m"
        }
    }

  # module.alb.aws_lb_listener.frontend_http_tcp[0] will be created
  + resource "aws_lb_listener" "frontend_http_tcp" {
      + arn               = (known after apply)
      + id                = (known after apply)
      + load_balancer_arn = (known after apply)
      + port              = 80
      + protocol          = "HTTP"
      + ssl_policy        = (known after apply)

      + default_action {
          + order            = (known after apply)
          + target_group_arn = (known after apply)
          + type             = "forward"
        }
    }

  # module.alb.aws_lb_target_group.main[0] will be created
  + resource "aws_lb_target_group" "main" {
      + arn                                = (known after apply)
      + arn_suffix                         = (known after apply)
      + deregistration_delay               = 300
      + id                                 = (known after apply)
      + lambda_multi_value_headers_enabled = false
      + load_balancing_algorithm_type      = (known after apply)
      + name                               = (known after apply)
      + name_prefix                        = "test"
      + port                               = 80
      + protocol                           = "HTTP"
      + proxy_protocol_v2                  = false
      + slow_start                         = 0
      + tags                               = {
          + "Environment" = "Test"
          + "Name"        = "test"
        }
      + target_type                        = "instance"
      + vpc_id                             = "vpc-0c35f33459bcaf9ae"

      + health_check {
          + enabled             = (known after apply)
          + healthy_threshold   = (known after apply)
          + interval            = (known after apply)
          + matcher             = (known after apply)
          + path                = (known after apply)
          + port                = (known after apply)
          + protocol            = (known after apply)
          + timeout             = (known after apply)
          + unhealthy_threshold = (known after apply)
        }

      + stickiness {
          + cookie_duration = (known after apply)
          + enabled         = (known after apply)
          + type            = (known after apply)
        }
    }

Plan: 3 to add, 0 to change, 0 to destroy.

------------------------------------------------------------------------

This plan was saved to: issue156.plan

To perform exactly these actions, run the following command to apply:
    terraform apply "issue156.plan"

[antonbabenko]

Thanks, @nahuel242 !

v5.5.0 has been just released.

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues. If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.