ECSctrl 0.3.0

ECSctrl - utility to deploy ECS services for humans

ECSctrl - ECS deployment for humans

ECSctrl allows you to interact w ECS task definition, service and SSM parameter store APIs with simple, easy to maintain template-driven ymls. It works by generating yml resource description from a template and passing it directly to boto3 function as parameters. You can reference boto3 documentation for information on expected data structure.

Template engine

ECSctrl uses Jinja2 under the hood. You can use any expression (values, includes, conditions, loops etc.) that is allowed by Jinja. For example common pattern is to keep environment configuration in a common file and include it in multiple task definitions.

Parameter sources

Jinja templates are fed with values from multiple sources given as command arguments:

1. env files with key-value pairs ie. -e production.env or --env-file=staging.env
2. json files ie. -j terraform-output.json or --env-file=infrastructure.json
3. key-value pairs provided as command arguments ie. -v env_name=jupiter or --var instance_type=small
4. system environment - turned on/off with --sys-env/--no-sys-env option; off by default

Authentication

ECSctrl uses boto3. Configure your aws credentials or set your environment variables as expected by boto3.

Usage examples

All command accept parameter sources as described above. All examples below use the same env file:

# production.env
env_name=production
desired_count=5
memory_limit=2048
app_version=latest
aws_region=us-west-1
target_group_arn=arn:aws:elasticloadbalancing:us-west-1:123456:targetgroup/web-backend/6b38ca93a923aecf
execution_role_arn=arn:aws:iam::123456:role/ecs_task_execution_role
task_role_arn=arn:aws:iam::123456:role/ecs_task_role
subnets=subnet-0296669bba,subnet-b5815d42f,subnet-9401e7ab
service_security_groups=sg-d2935617e5,sg-bb45c06af

Register new ECS task definition.

# task-defnition.yaml
family: {{ env_name }}-nginx
tags:
  ManagedBy: ECSctrl
  Environment: {{ env_name }}
executionRoleArn: {{ execution_role_arn }}
taskRoleArn: {{ task_role_arn }}
networkMode: awsvpc
cpu: 512
memory: {{ memory_limit }}
containerDefinitions:
  - name: ngninx
    image: nginx:{{ app_version }}
    memoryReservation: 512
    essential: true
    logConfiguration:
      logDriver: awslogs
      options:
        awslogs-group: {{ env_name }}/nginx
        awslogs-region: {{ aws_region }}
        awslogs-stream-prefix: nginx
        awslogs-create-group: "true"
    portMappings:
      - containerPort: 80
        hostPort: 80
    environment:
      - DEBUG=true
    secrets:
      - DATABASE_PASSWORD={{ env_name }}-DATABASE_PASSWORD
      - SESSION_SECRET_KEY={{ env_name }}-SESSION_SECRET_KEY

ecsctrl task-definition register -e production.env task-definition.yaml

Additional options:

• -c <cluster-name> / --update-services-in-cluster=<cluster-name> - updates all existing services which uses previous version of task definition (task definition family must match) in given cluster. Can be added multiple times for multiple clusters
• -w / --wait - wait for update of all services to finish. Command will fail if at least one of services will fail to update.

Create new ECS service

# service.yaml
serviceName: nginx
cluster: {{ env_name }}-ecs-cluster
tags:
  ManagedBy: ECSctrl
  Environment: {{ env_name }}
enableECSManagedTags: true
propagateTags: TASK_DEFINITION
desiredCount: {{ desired_count }}
launchType: FARGATE
loadBalancers:
  - targetGroupArn: {{ target_group_arn }}
    containerName: nginx
    containerPort: 80
taskDefinition: {{ env_name }}-nginx
deploymentConfiguration:
  maximumPercent: 200
  minimumHealthyPercent: 50
  deploymentCircuitBreaker:
    enable: true
    rollback: false
schedulingStrategy: REPLICA
deploymentController:
  type: ECS
networkConfiguration:
  awsvpcConfiguration:
    assignPublicIp: DISABLED
    subnets:
{% for subnet in subnets.split(',') %}
      - {{ subnet }}
{% endfor %}
    securityGroups:
{% for sg in service_security_groups.split(',') %}
      - {{ sg }}
{% endfor %}

ecsctrl service create -e production.env service.yaml

Additional options:

• -w / --wait - wait for service to be fully functional. Command will fail if service fails to start.

Update existing ECS service

Update command takes the same service definition file as create command. Payload is converted to match AWS API's requirements for service update - some field are renamed and some are removed.

ecsctrl service update -e production.env service.yaml

Additional options:

• -w / --wait - wait for service to be fully functional. Command will fail if service fails to start.

Create or update ECS service

Updates a service or creates a new one if not exists.

ecsctrl service create-or-update -e production.env service.yaml

Additional options:

• -w / --wait - wait for service to be fully functional. Command will fail if service fails to start or update.

Single command deployment

All-in-one - registers task definition and performs create-or-update of a service. Recommended to use in CIs. Takes both: task definition and service yaml file specs.

ecsctrl service deploy -e production.env task-definition.yaml service.yaml

Additional options:

• -w / --wait - wait for service to be fully functional. Command will fail if service fails to start or update.

Store secrets in SSM parameter store.

Secrets are represented in yaml as SSM name and value pairs. They're uploaded to parameter store as SecureStrings.

# secrets.yaml
{{ env_name }}-DATABASE_PASSWORD: 5w55ARXYbM3vUSVH
{{ env_name }}-SESSION_SECRET_KEY: VADGyLJscJsa4FF2

ecsctrl secrets store -e production.env secrets.yaml