ecs create_task_set does not create tasks (and obviously not propagate tags)

[suonto]

Moto ecs create_task_set does not result in running tasks. Additionally, it should propagate tags to the tasks, depending on service PropagateTags setting.

Pseudo context

Given service propagateTags is configured to "TASK_DEFINITION"
and task definition has TASK_DEF_TAGS
and os.environ["MOTO_ECS_SERVICE_RUNNING"] == "1"

ecs.create_task_set(...)

tasks = ecs.list_tasks(...), followed by ecs.describe_tasks(...)

assert one task is running
assert the task has TASK_DEF_TAGS

how to reproduce the issue

Mock aws, and then follow this:

TASK_DEF_TAGS: list[TagTypeDef] = [
    {
        "key": "test-task-def-tag-1",
        "value": "test-task-def-tag-1-value",
    },
    {
        "key": "test-task-def-tag-2",
        "value": "test-task-def-tag-2-value",
    },
]

ecs = boto3.client("ecs")

response = ecs.create_cluster(
    clusterName="test-cluster-a",
)

cluster_a = response["cluster"]

response = ecs.register_task_definition(
    family="test-family",
    containerDefinitions=[
        {
            "name": "test-container-def",
            "image": "foo",
            "memory": 256,
        }
    ],
    tags=TASK_DEF_TAGS,
)

task_def = response["taskDefinition"]

os.environ["MOTO_ECS_SERVICE_RUNNING"] = "1"

service_response = ecs.create_service(
    cluster=cluster_a["clusterArn"],
    serviceName="test-service",
    taskDefinition=task_def["taskDefinitionArn"],
    desiredCount=1,
    deploymentController={"type": "EXTERNAL"},
    propagateTags="TASK_DEFINITION",
)
service = service_response["service"]

ecs.create_task_set(
    service=service["serviceName"],
    cluster=cluster_a["clusterName"],
    externalId="test-ext-id",
    taskDefinition=task_def["taskDefinitionArn"],
    scale={"unit": "PERCENT", "value": 100},
    tags=task_def["tags"],
)

what you expected to happen

These assertions should be true:

list_tasks_response = ecs.list_tasks(
    cluster=cluster_a["clusterName"],
    serviceName=service["serviceName"],
)

task_arns = list_tasks_response["taskArns"]
assert len(task_arns) == 1

describe_tasks_response = ecs.describe_tasks(
    cluster=cluster_a["clusterName"],
    tasks=task_arns,
    include=["TAGS"],
)

tasks = describe_tasks_response["tasks"]

assert len(tasks) == 1
assert tasks[0]["tags"] == TASK_DEF_TAGS

what actually happens

Tasks are not created. That's easily explained by looking at the code that does not create any.

what version of Moto you're using

5.0.18, via pip

[bblommers]

Thanks for raising this @suonto - tasks are now created in moto==5.0.19.

I'm not too familiar with ECS, so please let us know if there are still any issues with this implementation.