Merge pull request #50 from oozou/terraform-test

chore: support blue-green deployment

Author: lycbrian

CHANGELOG.md

@@ -1,6 +1,21 @@
 # Change Log
 
+## [v1.4.0] - 2025-08-20
+
+### Added
+
+- Support blue-green deployment
+    - var: 
+        - is_enable_blue_green_deployment
+        - green_header_value
+        - alb_priority_green
+    - resource:  
+        - aws_lb_target_group.green
+        - aws_lb_listener_rule.green
+
+
 ## [v1.3.1] - 2025-04-09
+
 ### Added
 
 - lifecycle create_before_destroy for aws_lb_target_group

examples/terraform-test/main.tf

@@ -177,5 +177,8 @@ module "api_service" {
     }
   }
 
+  # Blue-Green Deployment
+  is_enable_blue_green_deployment = true
+
   tags = var.custom_tags
 }

examples/terraform-test/terraform.auto.tfvars

@@ -1,5 +1,5 @@
 prefix      = "oozou"
-environment = "devops"
+environment = "dev"
 name        = "demo"
 custom_tags = {
   "Remark" = "terraform-aws-ecs-service"

main.tf

@@ -149,6 +149,34 @@ resource "aws_lb_target_group" "this" {
     create_before_destroy = true
   }
 
+}
+
+resource "aws_lb_target_group" "green" {
+  count = local.is_create_target_group && var.is_enable_blue_green_deployment ? 1 : 0
+
+  name = format("%s-gn-tg", substr(local.container_target_group_object.name, 0, min(32, length(local.container_target_group_object.name))))
+
+  port                 = lookup(local.container_target_group_object, "port_mappings", null)[0].container_port
+  protocol             = lookup(local.container_target_group_object, "port_mappings", null)[0].container_port == 443 ? "HTTPS" : "HTTP"
+  vpc_id               = var.vpc_id
+  target_type          = "ip"
+  deregistration_delay = var.target_group_deregistration_delay
+
+  health_check {
+    interval            = lookup(var.health_check, "interval", null)
+    path                = lookup(var.health_check, "path", null)
+    timeout             = lookup(var.health_check, "timeout", null)
+    healthy_threshold   = lookup(var.health_check, "healthy_threshold", null)
+    unhealthy_threshold = lookup(var.health_check, "unhealthy_threshold", null)
+    matcher             = lookup(var.health_check, "matcher", null)
+  }
+
+  tags = merge(local.tags, { "Name" = format("%s-tg", substr(local.container_target_group_object.name, 0, min(29, length(local.container_target_group_object.name)))) })
+
+  lifecycle {
+    create_before_destroy = true
+  }
+
 }
 /* ------------------------------ Listener Rule ----------------------------- */
 resource "aws_lb_listener_rule" "this" {
@@ -189,6 +217,57 @@ resource "aws_lb_listener_rule" "this" {
 
   tags = local.tags
 }
+
+/* ------------------------------ Green Listener Rule ----------------------------- */
+resource "aws_lb_listener_rule" "green" {
+  count = local.is_create_target_group && var.is_enable_blue_green_deployment ? 1 : 0
+
+  listener_arn = var.alb_listener_arn
+  priority     = var.alb_priority_green
+
+  action {
+    type             = "forward"
+    target_group_arn = aws_lb_target_group.green[0].arn
+  }
+
+  condition {
+    path_pattern {
+      values = var.alb_paths == [] ? ["*"] : var.alb_paths
+    }
+  }
+
+  dynamic "condition" {
+    for_each = var.alb_host_header == null ? [] : [true]
+    content {
+      host_header {
+        values = [var.alb_host_header]
+      }
+    }
+  }
+
+  dynamic "condition" {
+    for_each = var.custom_header_token == "" ? [] : [true]
+    content {
+      http_header {
+        http_header_name = "custom-header-token" # Match value within cloudfront module
+        values           = [var.custom_header_token]
+      }
+    }
+  }
+
+  dynamic "condition" {
+    for_each = var.green_header_value == null ? [] : [true]
+    content {
+      http_header {
+        http_header_name = "green-header-name"
+        values           = [var.green_header_value]
+      }
+    }
+  }
+
+  tags = local.tags
+}
+
 /* -------------------------------------------------------------------------- */
 /*                                   Secret                                   */
 /* -------------------------------------------------------------------------- */

variables.tf

@@ -305,3 +305,25 @@ variable "container" {
   type        = any
   default     = {}
 }
+
+/* -------------------------------------------------------------------------- */
+/*                                Blue-Green Deployment                       */
+/* -------------------------------------------------------------------------- */
+variable "is_enable_blue_green_deployment" {
+  description = "Whether the service enable blue-green deployment"
+  type        = bool
+  default     = false
+}
+
+variable "green_header_value" {
+  description = "green header value in alb listener rule for blue-green deployment"
+  type        = string
+  default     = "green"
+}
+
+variable "alb_priority_green" {
+  description = "Priority of ALB rule https://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-listeners.html#listener-rules"
+  type        = string
+  default     = "110"
+}
+