EC2 `describe_volumes_modifications` should not return error if a volume has no modification history

[Gor027]

Describe the bug

Requesting describe_volumes_modifications for multiple volumes will return InvalidVolume.NotFound if any of the specified volumes have no modification history. While the documentation says the error should be returned if the volume does not exist.

Regression Issue

• Select this option if this issue appears to be a regression.

Expected Behavior

The expected behavior is not to get InvalidVolume.NotFound, instead get an empty response if all specified volumes do not have a modification history.

Current Behavior

The received response contains InvalidVolume.NotFound error, while the volume exists and is functional.

Reproduction Steps

1. Find a volume (or create one) that has no modification history
2. Send a describe_volumes_modifications setting the volume ID in the request

Alternatively, you can try to combine multiple volumes with/without modification history, and observe that the result is the same.

Possible Solution

No response

Additional Information/Context

No response

Version

aws-sdk-ec2 v1.97.0

Environment details (OS name and version, etc.)

Ubuntu 22.04

Logs

An error occurred (InvalidVolumeModification.NotFound) when calling the DescribeVolumesModifications operation: Modification for volume 'vol-asdafdf3e38341592' does not exist.

[landonxjames]

I was able to replicate this behavior with the Rust SDK and the AWS CLI. Since the CLI emits the same error this doesn't appear to be a Rust SDK issue. I suspect that EC2 is reusing the InvalidVolume.NotFound error for this case just to cut down on the total number of errors they have to manage, but I agree that it can be confusing given the documentation for that error code.