Create root.Driver instance at first usage

This allows for testing through injection of the driver root.

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

internal/modifier/graphics.go

@@ -29,16 +29,12 @@ import (
 
 // NewGraphicsModifier constructs a modifier that injects graphics-related modifications into an OCI runtime specification.
 // The value of the NVIDIA_DRIVER_CAPABILITIES environment variable is checked to determine if this modification should be made.
-func NewGraphicsModifier(logger logger.Interface, cfg *config.Config, image image.CUDA) (oci.SpecModifier, error) {
+func NewGraphicsModifier(logger logger.Interface, cfg *config.Config, image image.CUDA, driver *root.Driver) (oci.SpecModifier, error) {
 	if required, reason := requiresGraphicsModifier(image); !required {
 		logger.Infof("No graphics modifier required: %v", reason)
 		return nil, nil
 	}
 
-	driver := root.New(
-		root.WithLogger(logger),
-		root.WithDriverRoot(cfg.NVIDIAContainerCLIConfig.Root),
-	)
 	nvidiaCTKPath := cfg.NVIDIACTKConfig.Path
 
 	mounts, err := discover.NewGraphicsMountsDiscoverer(

internal/runtime/runtime.go

@@ -26,6 +26,7 @@ import (
 
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/config"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/info"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/root"
 )
 
 // Run is an entry point that allows for idiomatic handling of errors
@@ -76,8 +77,13 @@ func (r rt) Run(argv []string) (rerr error) {
 		r.logger.Infof("Running with config:\n%+v", cfg)
 	}
 
+	driver := root.New(
+		root.WithLogger(r.logger),
+		root.WithDriverRoot(cfg.NVIDIAContainerCLIConfig.Root),
+	)
+
 	r.logger.Debugf("Command line arguments: %v", argv)
-	runtime, err := newNVIDIAContainerRuntime(r.logger, cfg, argv)
+	runtime, err := newNVIDIAContainerRuntime(r.logger, cfg, argv, driver)
 	if err != nil {
 		return fmt.Errorf("failed to create NVIDIA Container Runtime: %v", err)
 	}

internal/runtime/runtime_factory.go

@@ -23,12 +23,13 @@ import (
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/config/image"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/info"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/root"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/modifier"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/oci"
 )
 
 // newNVIDIAContainerRuntime is a factory method that constructs a runtime based on the selected configuration and specified logger
-func newNVIDIAContainerRuntime(logger logger.Interface, cfg *config.Config, argv []string) (oci.Runtime, error) {
+func newNVIDIAContainerRuntime(logger logger.Interface, cfg *config.Config, argv []string, driver *root.Driver) (oci.Runtime, error) {
 	lowLevelRuntime, err := oci.NewLowLevelRuntime(logger, cfg.NVIDIAContainerRuntimeConfig.Runtimes)
 	if err != nil {
 		return nil, fmt.Errorf("error constructing low-level runtime: %v", err)
@@ -44,7 +45,7 @@ func newNVIDIAContainerRuntime(logger logger.Interface, cfg *config.Config, argv
 		return nil, fmt.Errorf("error constructing OCI specification: %v", err)
 	}
 
-	specModifier, err := newSpecModifier(logger, cfg, ociSpec)
+	specModifier, err := newSpecModifier(logger, cfg, ociSpec, driver)
 	if err != nil {
 		return nil, fmt.Errorf("failed to construct OCI spec modifier: %v", err)
 	}
@@ -61,7 +62,7 @@ func newNVIDIAContainerRuntime(logger logger.Interface, cfg *config.Config, argv
 }
 
 // newSpecModifier is a factory method that creates constructs an OCI spec modifer based on the provided config.
-func newSpecModifier(logger logger.Interface, cfg *config.Config, ociSpec oci.Spec) (oci.SpecModifier, error) {
+func newSpecModifier(logger logger.Interface, cfg *config.Config, ociSpec oci.Spec, driver *root.Driver) (oci.SpecModifier, error) {
 	rawSpec, err := ociSpec.Load()
 	if err != nil {
 		return nil, fmt.Errorf("failed to load OCI spec: %v", err)
@@ -82,7 +83,7 @@ func newSpecModifier(logger logger.Interface, cfg *config.Config, ociSpec oci.Sp
 		return modeModifier, nil
 	}
 
-	graphicsModifier, err := modifier.NewGraphicsModifier(logger, cfg, image)
+	graphicsModifier, err := modifier.NewGraphicsModifier(logger, cfg, image, driver)
 	if err != nil {
 		return nil, err
 	}

internal/runtime/runtime_factory_test.go

@@ -29,6 +29,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/config"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/root"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/test"
 )
 
@@ -63,6 +64,9 @@ func TestMain(m *testing.M) {
 
 func TestFactoryMethod(t *testing.T) {
 	logger, _ := testlog.NewNullLogger()
+	driver := root.New(
+		root.WithDriverRoot("/nvidia/driver/root"),
+	)
 
 	testCases := []struct {
 		description   string
@@ -143,6 +147,7 @@ func TestFactoryMethod(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.description, func(t *testing.T) {
+
 			bundleDir := t.TempDir()
 
 			specFile, err := os.Create(filepath.Join(bundleDir, "config.json"))
@@ -151,7 +156,7 @@ func TestFactoryMethod(t *testing.T) {
 
 			argv := []string{"--bundle", bundleDir, "create"}
 
-			_, err = newNVIDIAContainerRuntime(logger, tc.cfg, argv)
+			_, err = newNVIDIAContainerRuntime(logger, tc.cfg, argv, driver)
 			if tc.expectedError {
 				require.Error(t, err)
 			} else {