Terraform ECS Fargate

A set of Terraform templates used for provisioning web application stacks on AWS ECS Fargate.

Note: We suggest moving away from this template to our newer modular version. This repo will still receive updates to maintain compatability as terraform and the AWS providers evolve, but most newer features will be implemented in the module. You can find the module here: https://github.com/warnermedia/terraform-ecs-fargate-module

The templates are designed to be customized. The optional components can be removed by simply deleting the .tf file.

The templates are used for managing infrastructure concerns and, as such, the templates deploy a default backend docker image. We recommend using the fargate CLI for managing application concerns like deploying your actual application images and environment variables on top of this infrastructure. The fargate CLI can be used to deploy applications from your laptop or in CI/CD pipelines.

Components

base

These components are shared by all environments.

Name	Description	Optional
main.tf	AWS provider, output
state.tf	S3 bucket backend for storing Terraform remote state
ecr.tf	ECR repository for application (all environments share)

env/dev

These components are for a specific environment. There should be a corresponding directory for each environment that is needed.

Name	Description	Optional
main.tf	Terrform remote state, AWS provider, output
ecs.tf	ECS Cluster, Service, Task Definition, ecsTaskExecutionRole, CloudWatch Log Group
lb.tf	ALB, Target Group, S3 bucket for access logs
nsg.tf	NSG for ALB and Task
lb-http.tf	HTTP listener, NSG rule. Delete if HTTPS only	Yes
lb-https.tf	HTTPS listener, NSG rule. Delete if HTTP only	Yes
dashboard.tf	CloudWatch dashboard: CPU, memory, and HTTP-related metrics	Yes
role.tf	Application Role for container	Yes
cicd.tf	IAM user that can be used by CI/CD systems	Yes
autoscale-perf.tf	Performance-based auto scaling	Yes
autoscale-time.tf	Time-based auto scaling	Yes
logs-logzio.tf	Ship container logs to logz.io	Yes
secretsmanager.tf	Add a Secrets Manager secret with a CMK KMS key. Also gives app role and ECS task definition role access to read secrets from Secrets Manager	Yes
secrets-sidecar.tf	Adds a task definition configuration for deploying your app along with a sidecar container that writes your secrets manager secret to a file. Note that this is dependent upon opting in to secretsmanager.tf.	Yes
ssm-parameters.tf	Add a CMK KMS key for use with SSM Parameter Store. Also gives ECS task definition role access to read secrets from parameter store.	Yes
ecs-event-stream.tf	Add an ECS event log dashboard	Yes

Usage

Typically, the base Terraform will only need to be run once, and then should only need changes very infrequently. After the base is built, each environment can be built.

# Move into the base directory
$ cd base

# Sets up Terraform to run
$ terraform init

# Executes the Terraform run
$ terraform apply

# Now, move into the dev environment
$ cd ../env/dev

# Sets up Terraform to run
$ terraform init

# Executes the Terraform run
$ terraform apply

Important (after initial terraform apply)

The generated base .tfstate is not stored in the remote state S3 bucket. Ensure the base .tfstate is checked into your infrastructure repo. The default Terraform .gitignore generated by GitHub will ignore all .tfstate files; you'll need to modify this!

fargate-create

Alternatively you can use the fargate-create CLI to scaffold new projects based on this template.

install

curl -s get-fargate-create.turnerlabs.io | sh

create an input vars file (terraform.tfvars)

# app/env to scaffold
app = "my-app"
environment = "dev"

internal = true
container_port = "8080"
replicas = "1"
health_check = "/health"
region = "us-east-1"
aws_profile = "default"
saml_role = "admin"
vpc = "vpc-123"
private_subnets = "subnet-123,subnet-456"
public_subnets = "subnet-789,subnet-012"
tags = {
  application   = "my-app"
  environment   = "dev"
  team          = "my-team"
  customer      = "my-customer"
  contact-email = "me@example.com"
}

$ fargate-create -f terraform.tfvars

Additional Information

• Base README

• Environment dev README

Install pre-commit hook that checks terraform code for formatting

ln -s ../../pre-commit.sh .git/hooks/pre-commit