gcp.gce: Add instance group name

[punya]

Area(s)

area:gcp

Is your change request related to a problem? Please describe.

On GCE, instance groups can be used to organize the configuration and lifecycle of multiple VM instances as a single entity. I'd like to associate the instance group name with telemetry from its individual instances to help with grouping, in the same way that a cluster or namespace helps to group k8s pods.

Describe the solution you'd like

A new attribute gcp.gce.instance.group that is optionally populated on GCP instances. It can be retrieved as the value of the created-by instance metadata field.

Describe alternatives you've considered

• Fetching instance group at query time -- doesn't work if the instance no longer exists
• Using a label or naming convention -- fragile

Additional context

No response

[johnbryan]

Should/could this be cloud agnostic?

• https://docs.aws.amazon.com/autoscaling/ec2/userguide/auto-scaling-groups.html
• https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets

[joaopgrassi]

This would be a resource attribute, right? @punya do you plan to work/submit a PR for starting a discussion on it?