A terraform module to provides ecs service balanced on application load balancer
- ECS Service
- Support launch_type: "EC2" / "FARGATE"
- With ECS Task
- [Optional] With CloudWatch Log Group(s)
- [Optional] With IAM Role & attached IAM Policy
- [Optional] Service Autoscaling
See more details about Service Load Balancing in the official AWS docs.
- Input variables: See variables.tf
- Output variables: See outputs.tf
# The following related sources is out of scope on this module
#resource "aws_lb" "xxx" {}
#resource "aws_lb_lister" "xxx" {}
#resource "aws_lb_target_group" "xxx" {
# # "ip" for fargate, "instance" by the default
# target_type = "ip"
#}
# For launch_type: "FARGATE"
#resource "aws_subnet" "xxx" {}
#resource "aws_security_group" "xxx" {}
# Using aws service-linked-role
# Or $ aws iam create-service-linked-role --aws-service-name ecs.amazonaws.com
resource "aws_iam_service_linked_role" "ecs" {
aws_service_name = "ecs.amazonaws.com"
}
module "ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
name = "ex-app-api-service"
cluster_name = "${aws_ecs_cluster.ex_app.name}"
launch_type = "FARGATE"
# 1. Selected launch_type: "FARGATE" (cluster auto creating)
network_mode = "awsvpc"
subnet_ids = ["${aws_subnet.xxx.id}", "${aws_subnet.yyy.id}"]
security_group_ids = ["${aws_security_group.xxx.id}"]
# 2. Selected launch_type: "EC2" (cluster needs created by external)
#cluster_id = "${aws_ecs_cluster.ex_app.id}"
#cluster_name = "${aws_ecs_cluster.ex_app.cluster_name}"
#launch_type = "EC2"
# [Optional] customize ecs roles
task_role_arn = "${aws_iam_role.xxx.arn}"
# Maybe better off using aws service-linked-role (it's default modules behavior)
#execution_role_arn = "${aws_iam_role.yyy.arn}"
target_group_arn = "${aws_lb_target_group.ex_app_api.arn}"
#desired_count = 4
container_name = "ex-app-api" # same as "name" into container_definition
container_port = "80" # same as "containerPort" into container_definition
container_family = "ex-app-api"
container_definitions = <<TASK_DEFINITION
[
{
"name": "ex-app-api",
"essential": true,
"image": "${var.YOUR_AWS_ACCOUNT_ID}.dkr.ecr.${var.AWS_REGION}.amazonaws.com/ex-app-api:latest",
"cpu": 512,
"memory": 1024,
"portMappings": [
{
"hostPort": 0,
"containerPort": 80
}
],
"logConfiguration": {
"logDriver": "awslogs",
"options": {
"awslogs-group": "ex-app-api-service/container",
"awslogs-region": "${var.AWS_REGION}"
}
}
}
]
TASK_DEFINITION
# Optional to log_groups*
log_groups = ["ex-app-api/container"] # like same as "awslogs-group" at container_definition
log_groups_expiration_days = 30
log_groups_tags = {
Application = "ex-app-api"
}
}Currently aws_ecs_service.main.task_definition is ignored by lifecycle cause task_definition is updated often via continuous ecs deployment.
Although it is a difficult decision, we hope to support dynamic lifecycle featured by Terraform.
See detail: #1
As below U can create enhanced ecs-service using optional input-variables or others
module "ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
# ...
autoscale_iam_role_arn = "${data.aws_iam_role.ecs_autoscale_service_linked_role.arn}"
autoscale_min_capacity = 2
autoscale_max_capacity = 8
# Optional to scale_out_*_actions
#scale_out_ok_actions = []
scale_out_more_alarm_actions = ["${aws_sns_topic.ex_alert.arn}"]
scale_out_thresholds = {
cpu = 80
memory = 75
}
scale_out_step_adjustment = {
metric_interval_lower_bound = 0
scaling_adjustment = 1
}
# Optional to scale_in_*_actions
#scale_in_ok_actions = []
#scale_in_more_alarm_actions = []
scale_in_thresholds = {
cpu = 10
memory = 20
}
scale_in_step_adjustment = {
metric_interval_upper_bound = 0
scaling_adjustment = -1
}
}
data "aws_iam_role" "ecs_autoscale_service_linked_role" {
# Prepare creating a service-linked role (CLI)
# $ aws iam create-service-linked-role --aws-service-name ecs.amazonaws.com
# Ref: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/using-service-linked-roles.html
name = "AWSServiceRoleForApplicationAutoScaling_ECSService"
}See more details about Service Auto Scaling in the official AWS docs.
Maybe only use launch_type as "EC2"
module "ecs_cluster" {
source = "[email protected]:voyagegroup/tf_aws_ecs//cluster"
# ...
}
module "ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
cluster_id = "${module.api_ecs_cluster.cluster_id}"
cluster_name = "${module.api_ecs_cluster.cluster_name}"
# ...
}# Creating lb
#resource "ws_lb" "api" {}
#resource "ws_lb_listener" "api" {}
#resource "ws_lb_target_group" "api" {}
# Creating lb(-internal)
#resource "aws_lb" "api_internal" {
# internal = true
#}
#resource "aws_lb_listener" "api_internal" {}
#resource "aws_lb_target_group" "api_internal" {}
module "ecs_cluster" {
source = "[email protected]:voyagegroup/tf_aws_ecs//cluster"
# ...
}
module "api_ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
name = "api"
cluster_id = "${module.ecs_cluster.cluster_id}"
cluster_name = "${module.ecs_cluster.cluster_name}"
target_group_arn = "${aws_lb_target_group.api.arn}"
# ...
}
module "api_internal_ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
name = "api_internal"
cluster_id = "${module.ecs_cluster.cluster_id}"
cluster_name = "${module.ecs_cluster.cluster_name}"
target_group_arn = "${aws_lb_target_group.api_internal.arn}"
# ...
}resource "aws_lb" "api" {
# ...
}
resource "aws_lb_listener" "api" {
# ...
"default_action" {
target_group_arn = "${aws_lb_target_group.api.arn}"
type = "forward"
}
}
resource "aws_lb_target_group" "api" {
# ...
}
resource "aws_lb_listener_rule" "api_canary" {
listener_arn = "${aws_lb_listener.api.arn}"
priority = 99
action {
type = "forward"
target_group_arn = "${aws_lb_target_group.api_canary.arn}"
}
condition {
field = "host-header"
values = ["test.*"]
}
}
resource "aws_lb_target_group" "api_canary" {
# ...
}
module "ecs_cluster" {
source = "[email protected]:voyagegroup/tf_aws_ecs//cluster"
# ...
}
module "api_ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
name = "api"
cluster_id = "${module.ecs_cluster.cluster_id}"
cluster_name = "${module.ecs_cluster.cluster_name}"
target_group_arn = "${aws_lb_target_group.api.arn}"
# ...
}
module "api_canary_ecs_service" {
source = "[email protected]:voyagegroup/tf_aws_ecs//service_load_balancing"
name = "api_canary"
cluster_id = "${module.ecs_cluster.cluster_id}"
cluster_name = "${module.ecs_cluster.cluster_name}"
target_group_arn = "${aws_lb_target_group.api_canary.arn}"
# ...
}