[Bug]: aws_lb_listener is refreshing not quite correct

[FlexTickets]

Terraform Core Version

1.5.5

AWS Provider Version

5.12.0

Affected Resource(s)

aws_lb_listener

Expected Behavior

I've created alb listener by code:

resource "aws_lb_listener" "alb" {
  count                     = length(local.config)

  load_balancer_arn         = aws_lb.alb.arn
  port                      = local.config[count.index].port
  protocol                  = local.config[count.index].protocol

  tags = {
    Name                    = "${terraform.workspace}-alb-${local.config[count.index].port}"
    Description             = "${local.config[count.index]._comment}"
  }

  default_action {
    type                    = local.config[count.index].default_action
    forward {
        target_group {
          arn               = aws_lb_target_group.alb[count.index].arn
          weight            = 1
        }
        dynamic "stickiness" {
        for_each = { for k, v in [ local.config[count.index].stickiness ] : k => v if v != "" }
        content {
          duration          = local.config[count.index].stickiness
          enabled           = true
        }
      }
    }
  }
}

That is there is configuration block "forward" with subblock "stickiness". It's confirming by aws cli:

aws elbv2 describe-listeners --listener-arns arn:aws:elasticloadbalancing:eu-central-1:<account_id>:listener/app/cloud3-lb/397c8400222f6274/c8d08c40ceaf4bc5
{
    "Listeners": [
        {
            "ListenerArn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:listener/app/cloud3-lb/397c8400222f6274/c8d08c40ceaf4bc5",
            "LoadBalancerArn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:loadbalancer/app/cloud3-lb/397c8400222f6274",
            "Port": 8080,
            "Protocol": "HTTP",
            "DefaultActions": [
                {
                    "Type": "forward",
                    "TargetGroupArn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:targetgroup/cloud3-alb-tg-8080/fc885ff52dbf1936",
                    "Order": 1,
                    "ForwardConfig": {
                        "TargetGroups": [
                            {
                                "TargetGroupArn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:targetgroup/cloud3-alb-tg-8080/fc885ff52dbf1936",
                                "Weight": 1
                            }
                        ],
                        "TargetGroupStickinessConfig": {
                            "Enabled": true,
                            "DurationSeconds": 86400
                        }
                    }
                }
            ]
        }
    ]
}

And AWS console:

Actual Behavior

I've got in state file:

          "index_key": 1,
          "schema_version": 0,
          "attributes": {
            "alpn_policy": null,
            "arn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:listener/app/cloud3-lb/397c8400222f6274/c8d08c40ceaf4bc5",
            "certificate_arn": null,
            "default_action": [
              {
                "authenticate_cognito": [],
                "authenticate_oidc": [],
                "fixed_response": [],
                "forward": [],
                "order": 1,
                "redirect": [],
                "target_group_arn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:targetgroup/cloud3-alb-tg-8080/fc885ff52dbf1936",
                "type": "forward"
              }
            ],
            "id": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:listener/app/cloud3-lb/397c8400222f6274/c8d08c40ceaf4bc5",
            "load_balancer_arn": "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:loadbalancer/app/cloud3-lb/397c8400222f6274",
            "port": 8080,
            "protocol": "HTTP",
            "ssl_policy": "",
            "tags": {
              "Description": "am",
              "Name": "cloud3-alb-8080"
            },
            "tags_all": {
              "Description": "am",
              "Name": "cloud3-alb-8080"
            },
            "timeouts": null
          },

That is configuration block "forward" is empty. Accordingly, this leads to an update listener every apply.

Relevant Error/Panic Output Snippet

# aws_lb_listener.alb[1] will be updated in-place
  ~ resource "aws_lb_listener" "alb" {
        id                = "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:listener/app/cloud3-lb/397c8400222f6274/c8d08c40ceaf4bc5"
        tags              = {
            "Description" = "am"
            "Name"        = "cloud3-alb-8080"
        }
        # (5 unchanged attributes hidden)

      ~ default_action {
          - target_group_arn = "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:targetgroup/cloud3-alb-tg-8080/fc885ff52dbf1936" -> null
            # (2 unchanged attributes hidden)

          + forward {
              + stickiness {
                  + duration = 86400
                  + enabled  = true
                }
              + target_group {
                  + arn    = "arn:aws:elasticloadbalancing:eu-central-1:<account_id>:targetgroup/cloud3-alb-tg-8080/fc885ff52dbf1936"
                  + weight = 1
                }
            }
        }
    }

Terraform Configuration Files

alb.zip

Steps to Reproduce

unzip alb.zip
terraform workspace new cloud3
terraform init
terraform apply
terraform apply

Debug Output

No response

Panic Output

No response

Important Factoids

No response

References

No response

Would you like to implement a fix?

None

[github-actions]

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[justinretzolk]

Related #20200
Possibly Related #14119

[gdavison]

Related to #22526

[github-actions]

This functionality has been released in v5.36.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

I'm going to lock this issue 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 similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.