simulator

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/vmware/govmomi"
	"github.com/vmware/govmomi/lookup"

	lsim "github.com/vmware/govmomi/lookup/simulator"
	"github.com/vmware/govmomi/lookup/types"
	"github.com/vmware/govmomi/simulator"
)

func main() {
	model := simulator.VPX()

	// TODO: using simulator.Run() would be simpler,
	// but access to lookup namespace Registry is not exported in that case.
	// Using lookup/simulator.New() directly in this example gives us access.
	defer model.Remove()
	err := model.Create()
	if err != nil {
		log.Fatal(err)
	}

	s := model.Service.NewServer()
	defer s.Close()

	sdk := lsim.New()

	model.Service.RegisterSDK(sdk)

	ctx := context.Background()

	vc, err := govmomi.NewClient(ctx, s.URL, true)
	if err != nil {
		log.Fatal(err)
	}

	// Note that ServiceRegistration.Info is generated the first time RetrieveServiceContent()
	// is called, so we do that here before modifying the Info list.
	c, err := lookup.NewClient(ctx, vc.Client)
	if err != nil {
		log.Fatal(err)
	}

	// Get a pointer to the in-memory lookup.ServiceRegistration object, which we can modify directly.
	r := sdk.Get(*c.ServiceContent.ServiceRegistration).(*lsim.ServiceRegistration)

	// Change the NodeId
	for i := range r.Info {
		if r.Info[i].ServiceType.Type == "vcenterserver" {
			r.Info[i].NodeId = "example-id"
			break
		}
	}

	filter := &types.LookupServiceRegistrationFilter{
		ServiceType: &types.LookupServiceRegistrationServiceType{
			Product: "com.vmware.cis",
			Type:    "vcenterserver",
		},
	}

	info, err := c.List(ctx, filter)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(info[0].NodeId)

}

Output:

example-id