Add abbility to set SSL certificate via ARN

main.tf

@@ -74,6 +74,7 @@ resource "aws_s3_bucket_policy" "alb-logs" {
 }
 
 data "aws_acm_certificate" "this" {
+  count       = "${ lower(var.ssl_certificate_arn) == "none" ? 1 : 0 }"
   domain      = "${var.acm_cert_domain}"
   statuses    = ["ISSUED", "PENDING_VALIDATION"]
   most_recent = "${var.most_recent_certificate}"
@@ -90,7 +91,7 @@ module "alb" {
   vpc_id                    = "${var.vpc_id}"
 
   /////// Configure listeners and target groups ///////
-  https_listeners       = "${list(map("certificate_arn", "${data.aws_acm_certificate.this.arn}", "port", "${var.default_https_tcp_listeners_port}"))}"
+  https_listeners       = "${list(map("certificate_arn", "${element(concat(data.aws_acm_certificate.this.*.arn, list(var.ssl_certificate_arn)), 0)}", "port", "${var.default_https_tcp_listeners_port}"))}"
   https_listeners_count = "${var.default_https_tcp_listeners_count}"
 
   http_tcp_listeners       = "${list(map("port", "${var.default_http_tcp_listeners_port}", "protocol", "HTTP"))}"

variables.tf

@@ -95,6 +95,11 @@ variable "root_domain" {
   description = "Root domain in which custom DNS record for ALB would be created"
 }
 
+variable "ssl_certificate_arn" {
+  description = "ARN of SSL certificate to use for ALB"
+  default     = "none"
+}
+
 variable "tags" {
   type        = "map"
   description = "Additional tags for resources"