Return nvcdi.spec.Interface from GetSpec

Signed-off-by: Evan Lezar <elezar@nvidia.com>

pkg/nvcdi/lib.go

@@ -17,12 +17,17 @@
 package nvcdi
 
 import (
+	"github.com/NVIDIA/nvidia-container-toolkit/pkg/nvcdi/spec"
 	"github.com/sirupsen/logrus"
 	"gitlab.com/nvidia/cloud-native/go-nvlib/pkg/nvlib/device"
 	"gitlab.com/nvidia/cloud-native/go-nvlib/pkg/nvlib/info"
 	"gitlab.com/nvidia/cloud-native/go-nvlib/pkg/nvml"
 )
 
+type wrapper struct {
+	Interface
+}
+
 type nvcdilib struct {
 	logger        *logrus.Logger
 	nvmllib       nvml.Interface
@@ -60,6 +65,7 @@ func New(opts ...Option) Interface {
 		l.infolib = info.New()
 	}
 
+	var lib Interface
 	switch l.resolveMode() {
 	case ModeNvml:
 		if l.nvmllib == nil {
@@ -69,13 +75,30 @@ func New(opts ...Option) Interface {
 			l.devicelib = device.New(device.WithNvml(l.nvmllib))
 		}
 
-		return (*nvmllib)(l)
+		lib = (*nvmllib)(l)
 	case ModeWsl:
-		return (*wsllib)(l)
+		lib = (*wsllib)(l)
+	default:
+		// TODO: We would like to return an error here instead of panicking
+		panic("Unknown mode")
 	}
 
-	// TODO: We want an error here.
-	return nil
+	return &wrapper{Interface: lib}
+}
+
+// GetSpec combines the device specs and common edits from the wrapped Interface to a single spec.Interface.
+func (l *wrapper) GetSpec() (spec.Interface, error) {
+	deviceSpecs, err := l.GetAllDeviceSpecs()
+	if err != nil {
+		return nil, err
+	}
+
+	edits, err := l.GetCommonEdits()
+	if err != nil {
+		return nil, err
+	}
+
+	return spec.New(deviceSpecs, *edits.ContainerEdits)
 }
 
 // resolveMode resolves the mode for CDI spec generation based on the current system.