kubevela/docs/examples/registry/patch-replica.yaml

apiVersion: core.oam.dev/v1alpha2
kind: TraitDefinition
metadata:
  annotations:
    definition.oam.dev/description: "Manually scale the app"
  name: scaler
spec:
  appliesToWorkloads:
    - webservice
    - worker
  extension:
    template: |-
      patch: {
         spec: replicas: parameter.replicas
      }
      parameter: {
      	//+short=r
      	replicas: *1 | int
      }