ECS should support waiters

[ms-ati]

It would be very helpful to support waiting on ECS operations:
http://docs.aws.amazon.com/sdkforruby/api/Aws/ECS/Client.html#waiter_names-instance_method

For example, one must call deregister_container_instance in some cases, but there is no waiter to wait for that operation to complete.

[trevorrowe]

Thanks for submitting the feature request. I've added this as a feature request to our public backlog here: https://github.com/aws/aws-sdk-ruby/blob/master/FEATURE_REQUESTS.md#awsecsclient-waiters

[ms-ati]

Very cool, thanks for adding it to the list.

[euank]

@ms-ati
Good news, there are some ECS waiters now 😃

I specifically added :services_stable, :services_inactive, :tasks_running, and :tasks_stopped. These are included in the recent v2.1.1 release.

I did not add a waiter for deregister_container_instance because it's actually a synchronous operation.

If you have suggestions for other waiters, or run into issues with these, I'd be happy to look into it.
Cheers,
Euan

[ms-ati]

Sweet, thanks @euank I will try these out when I upgrade.