Add metrics support to service template

services/service/main.tf

@@ -13,6 +13,7 @@ resource "nomad_job" "service" {
     ingress_rule        = var.ingress_rule
     ingress_middlewares = var.ingress_middlewares
     healthcheck_path    = var.healthcheck_path
+    metrics_port_name   = var.metrics_port_name
 
     templates    = var.templates
     host_volumes = var.host_volumes

services/service/service_template.nomad

@@ -88,6 +88,12 @@ job "${name}" {
         timeout = "10s"
       }
 
+      %{ endif ~}
+      %{ if metrics_port_name != null ~}
+      meta {
+        metrics_addr = "$${NOMAD_ADDR_${metrics_port_name}}"
+      }
+
       %{ endif ~}
       tags = [
         %{ if ingress ~}

services/service/vars.tf

@@ -11,7 +11,13 @@ variable "image" {
 variable "service_port" {
   type        = number
   default     = null
-  description = "Port used by the service for ingress"
+  description = "Port number used by the service"
+}
+
+variable "metrics_port_name" {
+  type        = string
+  default     = null
+  description = "Name of port that /metrics can be scraped from"
 }
 
 variable "ingress" {
@@ -73,8 +79,8 @@ variable "templates" {
     change_signal   = optional(string)
     left_delimiter  = optional(string)
     right_delimiter = optional(string)
-    mount           = optional(bool)
-    env             = optional(bool)
+    mount           = optional(bool, true)
+    env             = optional(bool, false)
   }))
   default     = []
   description = "Templates to be used"