Fix computed count issue (#2)

* work around computed count issue

* explicitly add variable types and adjust docs

* add docs for new variable

* make vpc_id required

* use _count for consistency

README.md

@@ -60,8 +60,10 @@ module "blog_service" {
 | `namespace`                        |      ``         | Namespace (e.g. `cp` or `cloudposse`)                                            |   Yes    |
 | `stage`                            |      ``         | Stage (e.g. `prod`, `dev`, `staging`)                                            |   Yes    |
 | `name`                             |      ``         | Name  (e.g. `app` or `cluster`)                                                  |   Yes    |
+| `vpc_id`                           |      ``         | The VPC ID where generated ALB target group (if target_group_arn not set)        |   Yes    |
 | `target_group_arn`                 |      ``         | ALB target group ARN, if this is an empty string a new one will be generated     |    No    |
 | `listener_arns`                    |     `[]`        | A list of ALB listener ARNs to attach ALB listener rule to                       |    No    |
+| `listener_arns_count`              |      `0`        | The number of elements in the listener_arns list                                 |    No    |
 | `deregistration_delay`             |     `15`        | The amount of time to wait in seconds while deregistering target                 |    No    |
 | `health_check_path`                |     `/`         | The destination for the health check request                                     |    No    |
 | `health_check_timeout`             |     `10`        | The amount of time to wait in seconds before failing a health check request      |    No    |
@@ -72,9 +74,8 @@ module "blog_service" {
 | `priority`                         |     `100`       | The priority for the rule between 1 and 50000 (1 being highest priority)         |    No    |
 | `port`                             |     `80`        | The port for generated ALB target group (if target_group_arn not set)            |    No    |
 | `protocol`                         |    `HTTP`       | The protocol for generated ALB target group (if target_group_arn not set)        |    No    |
-| `vpc_id`                           |      ``         | The VPC ID where generated ALB target group (if target_group_arn not set)        |    No    |
-| `paths`                            |     `[]`        | Path pattern to match (a maximum of 1 can be defined)                            |    No    |
-| `hosts`                            |     `[]`        | Hosts to match in Hosts header                                                   |    No    |
+| `paths`                            |     `[]`        | Path pattern to match (a maximum of 1 can be defined), required if hosts not set |    No    |
+| `hosts`                            |     `[]`        | Hosts to match in Hosts header, required if paths not set                        |    No    |
 | `attributes`                       |     `[]`        | Additional attributes (e.g. `1`)                                                 |    No    |
 | `tags`                             |     `{}`        | Additional tags  (e.g. `map("BusinessUnit","XYZ")`                               |    No    |
 | `delimiter`                        |     `-`         | Delimiter to be used between `namespace`, `stage`, `name` and `attributes`       |    No    |
@@ -168,4 +169,4 @@ or [hire us][hire] to help build your next cloud platform.
 [igor_img]: http://s.gravatar.com/avatar/bc70834d32ed4517568a1feb0b9be7e2?s=144
 [igor_web]: https://github.com/goruha/
 [sarkis_img]: https://avatars3.githubusercontent.com/u/42673?s=144&v=4
-[sarkis_web]: https://github.com/sarkis/
+[sarkis_web]: https://github.com/sarkis/

main.tf

@@ -42,7 +42,7 @@ resource "aws_lb_target_group" "default" {
 }
 
 resource "aws_lb_listener_rule" "paths" {
-  count        = "${length(var.paths) > 0 && length(var.hosts) == 0 ? length(var.listener_arns) : 0}"
+  count        = "${length(var.paths) > 0 && length(var.hosts) == 0 ? var.listener_arns_count : 0}"
   listener_arn = "${var.listener_arns[count.index]}"
   priority     = "${var.priority + count.index}"
 
@@ -58,7 +58,7 @@ resource "aws_lb_listener_rule" "paths" {
 }
 
 resource "aws_lb_listener_rule" "hosts" {
-  count        = "${length(var.hosts) > 0 && length(var.paths) == 0 ? length(var.listener_arns) : 0}"
+  count        = "${length(var.hosts) > 0 && length(var.paths) == 0 ? var.listener_arns_count : 0}"
   listener_arn = "${var.listener_arns[count.index]}"
   priority     = "${var.priority + count.index}"
 
@@ -74,7 +74,7 @@ resource "aws_lb_listener_rule" "hosts" {
 }
 
 resource "aws_lb_listener_rule" "hosts_paths" {
-  count        = "${length(var.paths) > 0 && length(var.hosts) > 0 ? length(var.listener_arns) : 0}"
+  count        = "${length(var.paths) > 0 && length(var.hosts) > 0 ? var.listener_arns_count : 0}"
   listener_arn = "${var.listener_arns[count.index]}"
   priority     = "${var.priority + count.index}"
 

variables.tf

@@ -1,12 +1,15 @@
 variable "namespace" {
+  type        = "string"
   description = "Namespace, which could be your organization name, e.g. `cp` or `cloudposse`"
 }
 
 variable "stage" {
+  type        = "string"
   description = "Stage, e.g. `prod`, `staging`, `dev`, or `test`"
 }
 
 variable "name" {
+  type        = "string"
   description = "Solution name, e.g. `app`"
 }
 
@@ -29,6 +32,7 @@ variable "tags" {
 }
 
 variable "target_group_arn" {
+  type        = "string"
   default     = ""
   description = "ALB target group ARN, if this is an empty string a new one will be generated"
 }
@@ -39,37 +43,50 @@ variable "listener_arns" {
   description = "A list of ALB listener ARNs to attach ALB listener rule to"
 }
 
+variable "listener_arns_count" {
+  type        = "string"
+  default     = "0"
+  description = "The number of ARNs in listener_arns, this is necessary to work around a limitation in Terraform where counts cannot be computed"
+}
+
 variable "deregistration_delay" {
+  type        = "string"
   default     = "15"
   description = "The amount of time to wait in seconds while deregistering target"
 }
 
 variable "health_check_path" {
+  type        = "string"
   default     = "/"
   description = "The destination for the health check request"
 }
 
 variable "health_check_timeout" {
+  type        = "string"
   default     = "10"
   description = "The amount of time to wait in seconds before failing a health check request"
 }
 
 variable "health_check_healthy_threshold" {
+  type        = "string"
   default     = "2"
   description = "The number of consecutive health checks successes required before healthy"
 }
 
 variable "health_check_unhealthy_threshold" {
+  type        = "string"
   default     = "2"
   description = "The number of consecutive health check failures required before unhealthy"
 }
 
 variable "health_check_interval" {
+  type        = "string"
   default     = "15"
   description = "The duration in seconds in between health checks"
 }
 
 variable "health_check_matcher" {
+  type        = "string"
   default     = "200-399"
   description = "The HTTP response codes to indicate a healthy check"
 }
@@ -99,18 +116,17 @@ variable "target_type" {
 
 variable "vpc_id" {
   type        = "string"
-  default     = ""
   description = "The VPC ID where generated ALB target group will be provisioned (if target_group_arn not set)"
 }
 
 variable "hosts" {
   type        = "list"
   default     = []
-  description = "Hosts to match in Hosts header"
+  description = "Hosts to match in Hosts header, at least one of hosts or paths must be set"
 }
 
 variable "paths" {
   type        = "list"
   default     = []
-  description = "Path pattern to match (a maximum of 1 can be defined)"
+  description = "Path pattern to match (a maximum of 1 can be defined), at least one of hosts or paths must be set"
 }