Sort results from EC2 API

Question

Hello,

I am starting with AWS SDK (for Go v2) and I cannot get my head wrapped around pagination - specifically I am unable to find out how do I sort list of any resource for example. It looks like DescribeInstanceTypes always return types in random order and there is literally nothing in the documentation about sort order. How pagination is useful when order is always random? I do not understand, is this only to workaround API limits/throttling? Are applications supposed to do ordering on their own?

Thanks for explanation, cheers!

Answer

Hello Lzap,

You can order your results in your own. For example, with the AWS CLI you can use [JMESPath](https://jmespath.org/specification.html#sort-by) as it indicates the [official documentation](https://docs.aws.amazon.com/cli/latest/userguide/cli-usage-filter.html):

As an example, using AWS CLI you can order the DescribeInstanceTypes API invoking the API as:

`aws ec2 describe-instance-types --query 'sort_by(InstanceTypes, &InstanceType)[].InstanceType'`

Hope it helps.

Answer

Sorting isn't supported server-side, so is done client-side after results are returned by the API (e.g. the CLI example Joan_B mentioned).  You can filter server-side with some API calls by passing a Filter parameter.  That, and pagination, are for coping with large numbers of records.

Sort results from EC2 API

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