Add kube_deployment_owner

[Syndlex]

What would you like to be added:

There are more and more Operators in the ecosystem. Some of them just start Deployments and it would be nice to get the owner of those deployments

Why is this needed:

Add kube_deployment_owner like the kube_pod_owner

Describe the solution you'd like

Additional context

[richabanker]

Is owner a bounded label? What are the cardinality implications of this label?

[Syndlex]

Hey,

What is a bounded label? Haven't heard that term and Google isn't helping.

I would say the owner ist the object referenced in the owner reference of the deployment.
Like the owner of a pod can be a deployment.

[richabanker]

/cc

[dgrisonnet]

/triage accepted

[dgrisonnet]

@Syndlex Richa was referring to the cardinality of the label.

To quote the Prometheus doc:

CAUTION: Remember that every unique combination of key-value label pairs represents a new time series, which can dramatically increase the amount of data stored. Do not use labels to store dimensions with high cardinality (many different label values), such as user IDs, email addresses, or other unbounded sets of values.

In this case, Richa was asking if there is a finite number of owner values for the label. This is important because unbounded label values can cause cardinality explostions which essentially can bring down monitoring platforms.