aws-ec2-backup-script.php

<?php

$volumeId = 'vol-id';

$daysLimit = 3;

$ownerId = '0123456789101';
$tag = false; // tag name or false
$date = date('Y-m-d H:i:s');

$resultJson = `aws ec2 create-snapshot --volume-id $volumeId --description "site.appshed.com $date"`;
if($tag){
   $snapshotInfo = json_decode($resultJson);
   $snapshotId = $snapshotInfo->SnapshotId;
`/usr/local/bin/aws ec2 create-tags --resources $snapshotId --tags Key=Name,Value="$tag"`;
}

$snapshotsList  = `aws ec2 describe-snapshots --owner-ids $ownerId`;

$snapshots = json_decode($snapshotsList);

foreach ($snapshots->Snapshots as $snapshot) {

    if ($snapshot->VolumeId == $volumeId) {

        $startDate = new DateTime($snapshot->StartTime);

        $interval = $startDate->diff(new DateTime());

        echo $interval->format('%R%a %h:%i:%S') . PHP_EOL;

        if ($interval->format('%a') >= $daysLimit) {
            echo "Delete {$snapshot->SnapshotId}" . PHP_EOL;
            $deleteRequest = `aws ec2 delete-snapshot --snapshot-id {$snapshot->SnapshotId}`;
            echo $deleteRequest;
        }

    }
}