// GetContainerInstances will return a slice of ECS Container Instances within a cluster
func GetContainerInstances(svc *ecs.ECS, ec2svc *ec2.EC2, cluster *string) (containerInstances []*ecs.ContainerInstance, instances []*ec2.Reservation, e error) {
var ciArns []*string
// List clusters
reqParams := &ecs.ListContainerInstancesInput{
Cluster: cluster,
MaxResults: aws.Int64(100),
NextToken: aws.String(""),
}
// Loop through tokens until no more results remain
for {
resp, err := svc.ListContainerInstances(reqParams)
// Error check
if err != nil {
return nil, nil, fmt.Errorf("ecs.ListContainerInstances: %s", err.Error())
}
// Expand slice of container instances and append to our comprehensive list
ciArns = append(ciArns, resp.ContainerInstanceArns...)
// Cycle token
if resp.NextToken != nil {
reqParams.NextToken = resp.NextToken
} else {
// Kill loop ... out of response pages
break
}
}
// Describe the tasks that we just got back
ciResponse, err := svc.DescribeContainerInstances(&ecs.DescribeContainerInstancesInput{
Cluster: cluster,
ContainerInstances: ciArns,
})
if err != nil {
return nil, nil, fmt.Errorf("ecs.DescribeContainerInstances: %s", err.Error())
}
var instanceIds []*string
for _, k := range ciResponse.ContainerInstances {
instanceIds = append(instanceIds, k.Ec2InstanceId)
}
// Create a map of container instances by ci arn...
// Note: Will work for <= 1000 instances w/o having to use NextToken
ec2Resp, err := ec2svc.DescribeInstances(&ec2.DescribeInstancesInput{
InstanceIds: instanceIds,
})
if err != nil {
return nil, nil, fmt.Errorf("ec2.DescribeInstances: %s", err.Error())
}
return ciResponse.ContainerInstances, ec2Resp.Reservations, nil
}
func containerInstances(e *ecspkg.ECS, cluster *string) []*string {
instances := []*string{}
next := aws.String("")
for next != nil {
input := ecspkg.ListContainerInstancesInput{
Cluster: cluster,
}
if next != nil && *next != "" {
input.NextToken = next
}
output, err := e.ListContainerInstances(&input)
log.Check(err)
instances = append(instances, output.ContainerInstanceArns...)
next = output.NextToken
}
return instances
}