Build an ECS Fargate cluster and launch a simple Go application Docker container on top of it. Here are the steps for launching the Terraform code and the Go application.

Terraform Code(Github)

Environment

• VPC
• Two public subnets.
• One ECS cluster.
• ALB

Instructions for launching the Go application

Create a repository in ECR

Build and push the Docker image to the ECR repository

Create a Docker image of the actual Go application to run. Use the following commands to build the Docker image and push it to the ECR repository.

cd fargate-go-example/docker/docker-image

aws ecr get-login-password --region ap-northeast-1 | docker login --username AWS --password-stdin <Your AWS account number>.dkr.ecr.<Your region>.amazonaws.com

docker build -t go-example .

docker tag go-example:latest <Your AWS account number>.dkr.ecr.<Your region>.amazonaws.com/go-example:latest

docker push <Your AWS account number>..dkr.ecr.<Your region>.amazonaws.com/go-example:latest

ECS Operations.

ECS CLI Installation.

Install the CLI to operate the ECS on your PC. See the AWS documentation for instructions on how to install and initially configure it.

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ECS_CLI_installation.html

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ECS_CLI_Configuration.html

Update the image name of docker-compose.yml as a base for ECS task definitions.

We will use docker-compose.yml as an input to the ecs-cli compose command that we will run later. Change the part of the following image

cd fargate-go-example/docker
vim docker-compose.yml

version: '3'

services:
  fargate-go-example:
    image: ' <AWS account number>.dkr.ecr.ap-northeast-1.amazonaws.com/go-example:latest'
    ports:
      - '8080:8080'

Modification of ecs-params.yml as a base for ECS task definition

Use ecs-params.yml as an input to the ecs-cli compose command to be run later.

Replace the following values of subnets and security_groups with the IDs of the ones you created with Terraform.

version: 1
task_definition:
  task_execution_role: ecsTaskExecutionRole
  ecs_network_mode: awsvpc
  task_size:
    mem_limit: 0.5GB
    cpu_limit: 256
run_params:
  network_configuration:
    awsvpc_configuration:
      subnets:
        - "subnet-0d9ee166fc862a5df"
        - "subnet-02821c5131011d174"
      security_groups:
        - "sg-08c2299a6c28415f8"
      assign_public_ip: ENABLED

Deploy ECS Service

Start the ECS service. Execute the following command. Enter the ARN of the target group created by erraform in –target-group-arn.

timeout 30m ecs-cli compose \
  --file docker-compose.yml \
  --ecs-params ecs-params.yml \
  --project-name fargate-go-example\
  --cluster fargate-go-example \
 service up --launch-type FARGATE \
 --container-name fargate-go-example \
 --container-port 8080 \
 --target-group-arn arn:aws:elasticloadbalancing:ap-northeast-1:xxxxxxxxxxxxx:targetgroup/fargate-go-example/xxxxxxxxxxxxxxx \
 --region ap-northeast-1 \
 --timeout 30