from aws_cdk import (
    aws_autoscaling as autoscaling,
    aws_ec2 as ec2,
    aws_ecs as ecs,
    App, Stack
)

app = App()
stack = Stack(app, "sample-ecs-task-placement")

# Create a cluster
vpc = ec2.Vpc(
    stack, "Vpc",
    max_azs=2
)

cluster = ecs.Cluster(
    stack, "EcsCluster",
    vpc=vpc
)

asg = autoscaling.AutoScalingGroup(
    stack, "DefaultAutoScalingGroup",
    instance_type=ec2.InstanceType("t2.micro"),
    machine_image=ecs.EcsOptimizedImage.amazon_linux2(),
    vpc=vpc,
)
capacity_provider = ecs.AsgCapacityProvider(stack, "AsgCapacityProvider",
    auto_scaling_group=asg
)
cluster.add_asg_capacity_provider(capacity_provider)

# Create a task definition with placement constraints
task_definition = ecs.Ec2TaskDefinition(
    stack, "TaskDef"
)

container = task_definition.add_container(
    "web",
    image=ecs.ContainerImage.from_registry("nginx:latest"),
    memory_limit_mib=256,
)
port_mapping = ecs.PortMapping(
    container_port=80,
    host_port=8080,
    protocol=ecs.Protocol.TCP
)
container.add_port_mappings(port_mapping)

# Create Service
service = ecs.Ec2Service(
    stack, "Service",
    cluster=cluster,
    task_definition=task_definition,
    placement_constraints=[
        ecs.PlacementConstraint.distinct_instances()
    ]
)

service.add_placement_strategies(
    ecs.PlacementStrategy.packed_by(ecs.BinPackResource.MEMORY))
service.add_placement_strategies(
    ecs.PlacementStrategy.spread_across(
        ecs.BuiltInAttributes.AVAILABILITY_ZONE))
app.synth()