Add deregistration_delay argument (#34)

Author: mksm

main.tf

@@ -30,10 +30,11 @@ resource "aws_s3_bucket" "log_bucket" {
 }
 
 resource "aws_alb_target_group" "target_group" {
-  name     = "${var.alb_name}-tg"
-  port     = "${var.backend_port}"
-  protocol = "${upper(var.backend_protocol)}"
-  vpc_id   = "${var.vpc_id}"
+  name                 = "${var.alb_name}-tg"
+  port                 = "${var.backend_port}"
+  protocol             = "${upper(var.backend_protocol)}"
+  vpc_id               = "${var.vpc_id}"
+  deregistration_delay = "${var.deregistration_delay}"
 
   health_check {
     interval            = "${var.health_check_interval}"

variables.tf

@@ -46,6 +46,11 @@ variable "cookie_duration" {
   default     = 1
 }
 
+variable "deregistration_delay" {
+  description = "The amount time to wait before changing the state of a deregistering target from draining to unused."
+  default     = 300
+}
+
 variable "force_destroy_log_bucket" {
   description = "If set to true and if the log bucket already exists, it will be destroyed and recreated."
   default     = false