Labels as a list or array of values

General Discussions
1

hi all
I have a requirement where I need label which can be a list of values. for ex:
label:
app: app1, app2, app3

as based on these values my matchLabels can be any of these and if it matches any of these label values it will handle the network policy

Kind: Deployment
Meta:
Label:
name: app4
team: training
app: app1, app2, app3

my network policy stuff could be like this

kind: CiliumNetworkPolicy
specs:

  • description: “some description”
    endpointSelector:
    matchLabels:
    role: backend
    ingress:
    • fromEndpoint:
      matchLabels:
      “k8s:app”: “app1”

How do I set label as a list or array of values or how should I take it forward

2

Labels are intended to be singular key:value pairs and don’t have inherit logic to parse arrays of items in a single label.

For more information, see the Labels and Selectors | Kubernetes section of the docs.

3

Is there some work around to achieve it if labels cant have multiple values?

4

The easiest is to add more labels as descriptors. Break down the array into multiple key:value pairs as descriptors and use those in your selector.

labels:
  name: my-awesome-thing
  environment: dev
  app: awesome-app
  component: webserver

apiVersion: "cilium.io/v2"
kind: CiliumNetworkPolicy
metadata:
  name: "my-network-policy"
  namespace: dev
spec:
  endpointSelector:
    matchLabels:
      role: backend
  ingress:
  - fromEndpoints:
    - matchLabels:
        k8s:name: my-awesome-thing
        k8s:app: awesome-app
        k8s:component: webserver