Add VmEndpointRequest in hcn for eventual usage in the shim

[dcantah]

HCS today for adding a network adapter to a virtual machine sets up the switch port itself by making a VmEndpointRequest. There are cases where we will want to do this ourselves, and we need the switch ID for this which will only exist after this request.

Below is an example of using this:

        portID, err := guid.NewV4()
	if err != nil {
		return errors.Wrap(err, "failed to generate guid for port")
	}

	vmEndpointRequest := hcn.VmEndpointRequest{
		PortId:           portID,
		VirtualNicName:   fmt.Sprintf("%s--%s", "cool-NIC-ID", portID),
		VirtualMachineId: guid.GUID{},
	}

	m, err := json.Marshal(vmEndpointRequest)
	if err != nil {
		return errors.Wrap(err, "failed to marshal endpoint request json")
	}

	if err := hcn.ModifyEndpointSettings(endpointID, &hcn.ModifyEndpointSettingRequest{
		ResourceType: hcn.EndpointResourceTypePort,
		RequestType:  hcn.RequestTypeAdd,
		Settings:     json.RawMessage(m),
	}); err != nil {
		return errors.Wrap(err, "failed to configure switch port")
	}

	// Get updated endpoint with new fields (need switch ID)
	ep, err := hcn.GetEndpointByID(endpointID)
	if err != nil {
		return errors.Wrapf(err, "failed to get endpoint %q", endpointID)
	}

	type ExtraInfo struct {
		Allocators []struct {
			SwitchId         string
			EndpointPortGuid string
		}
	}

	var exi ExtraInfo
	if err := json.Unmarshal(ep.Health.Extra.Resources, &exi); err != nil {
		return errors.Wrapf(err, "failed to unmarshal resource data from endpoint %q", endpointID)
	}

	if len(exi.Allocators) == 0 {
		return errors.New("no resource data found for endpoint")
	}

	// NIC should only ever belong to one switch but there are cases where there's more than one allocator
	// in the returned data. It seems they only ever contain empty strings so search for the first entry
	// that actually contains a switch ID and that has the matching port GUID we made earlier.
	var switchID string
	for _, allocator := range exi.Allocators {
		if allocator.SwitchId != "" && strings.ToLower(allocator.EndpointPortGuid) == portID.String() {
			switchID = allocator.SwitchId
			break
		}
	}

Signed-off-by: Daniel Canter dcanter@microsoft.com

[dcantah]

It isn't adding @microsoft/containerplat as a reviewer 😮

[katiewasnothere]

just curious: why did you change these?

[dcantah]

Easier to unmarshal into something as it's just bytes instead of an interface

[dcantah]

var exi ExtraInfo
if err := json.Unmarshal(ep.Health.Extra.Resources, &exi); err != nil {
	return errors.Wrapf(err, "failed to unmarshal resource data from endpoint %q", endpointID)
}

[katiewasnothere]

ah, good point

[katiewasnothere]

LGTM