AWS Cloudwatch PHP SDK返回未排序的指标统计信息

Question

I am currently extracting CloudWatch metrics statistics with the aws php sdk.

Unfortunately the getMetricStatistics method is returning unsorted results. I wonder why it is not sorted by Timestamp ASC. Does anyone know how to get sorted results from Cloudwatch?

my code

$result = $this->client->getMetricStatistics(array(
        'Namespace'  => 'My.Namespace',
        'MetricName' => 'my-metric',
        'StartTime'  => strtotime('-1 days'),
        'EndTime'    => strtotime('now'),
        'Period'     => 300,
        'Statistics' => array('Average'),
));

and the result

array (size=7)
  0 => 
    array (size=3)
      'Timestamp' => string '2014-04-16T10:53:00Z' (length=20)
      'Unit' => string 'Count' (length=5)
      'Average' => string '9.998594711316002' (length=17)
  1 => 
    array (size=3)
      'Timestamp' => string '2014-04-16T11:43:00Z' (length=20)
      'Unit' => string 'Count' (length=5)
      'Average' => string '0.7908148450858722' (length=18)
  2 => 
    array (size=3)
      'Timestamp' => string '2014-04-16T11:08:00Z' (length=20)
      'Unit' => string 'Count' (length=5)
     'Average' => string '5.402251656252796' (length=17)
  3 => 
    array (size=3)
      'Timestamp' => string '2014-04-16T11:03:00Z' (length=20)
      'Unit' => string 'Count' (length=5)
      'Average' => string '8.958888493053081' (length=17)

Thanks for your help!

J.

UPDATE

I still did not manage to get sorted results directly from the method call. So I used usort as suggested by @Svenskunganka

usort($result['Datapoints'], function($a, $b) {
    if($a['Timestamp'] == $b['Timestamp']) {
        return 0;
    }
    return ($a['Timestamp'] < $b['Timestamp']) ? -1 : 1;
});

I am still looking for the perfect way to get sorted results. If anyone has a clue, I would be really thankful.

Answer 1

There is no way to get sorted results from GetMetricStatistics, you have to sort the datapoints yourself.

"GetMetricStatistics does not return the data in chronological order."

Source: http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_GetMetricStatistics.html