Using the WaitUntil method to check if EBS Storage is deleted

Question

I am using the latest PHP Toolkit provided by Amazon to manipulate my EC2 Instances

I use the following code to check if the drive is available or not

$this->client->waitUntil('__VolumeStatus', array(
        'VolumeIds' => array($volumeId),
        'waiter.success.value' => VolumeState::AVAILABLE
    ));

Problem is that there is no status defined as DELETED. Only available options are given below

class VolumeState extends Enum
{
  const CREATING = 'creating';
  const AVAILABLE = 'available';
  const IN_USE = 'in-use';
  const DELETING = 'deleting';
  const ERROR = 'error';
}

Is there a clean way to stop the PHP process until the drive is deleted?

What would be the reason why you want to wait until the volume is deleted? — datasage, Sep 19 '13 at 15:51

score 2 · Answer 1 · answered Sep 19 '13 at 17:32

The way EBS works is that once the volume is deleted you won't see it any more. Logically, there's no reason to have a "deleted" status. There is no notion of a "Soft Delete" or "Undelete", which is what would require a "Deleted" status.

The absence of the volume from the DescribeVolumes response would be how this would work at the EBS API layer: http://docs.aws.amazon.com/AWSSDKforPHP/latest/#m=AmazonEC2/describe_volumes

At the Web Service SDK level, EBS will return an Error if you try to describe a volume that doesn't exist. Due to my lack of PHP familiarity, I'm not sure how that translates in PHP.

A guess (from someone who has never written a line of PHP Code!) would be something like:

do {
  $response = $ec2->describe_volumes($volumeId);
} while (! $response.isOk)

This should be done using the "waiter" infrastructure in the SDK rather than in while loop as you're already doing for availability.

Using the WaitUntil method to check if EBS Storage is deleted

1 Answers1