kubevela/docs/examples/registry/for-loop.yaml

apiVersion: core.oam.dev/v1alpha2
kind: TraitDefinition
metadata:
  name: expose
spec:
  extension:
    template: |
      parameter: {
      	domain: string
      	http: [string]: int
      }

      outputs: {
      	for k, v in parameter.http {
      		"\(k)": {
      			apiVersion: "v1"
      			kind:       "Service"
      			spec: {
      				selector:
      					app: context.name
      				ports: [{
      					port:       v
      					targetPort: v
      				}]
      			}
      		}
      	}
      }