/// <summary>
/// Gets a list of instance ids from a cluster and instance arns
/// </summary>
/// <param name="arns"></param>
/// <returns></returns>
private async Task <List <string> > GetAwsClusterInstancesIds(List <string> arns)
{
string awsRegion = context.AppSettings.SettingsConfig.AwsRegion;
string awsCluster = context.AppSettings.SettingsConfig.AwsClusterName;
AmazonECSClient ecs = new AmazonECSClient(Amazon.RegionEndpoint.GetBySystemName(awsRegion));
ecsModel.DescribeContainerInstancesRequest clusterRequest = new ecsModel.DescribeContainerInstancesRequest();
clusterRequest.Cluster = awsCluster;
clusterRequest.ContainerInstances = arns;
var items = await ecs.DescribeContainerInstancesAsync(clusterRequest);
return(items.ContainerInstances.Where(t => t.RunningTasksCount > 0).Select(t => t.Ec2InstanceId).ToList());
}