Extend nvidia-ctk config command to allow options to be set

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

CHANGELOG.md

@@ -4,9 +4,9 @@
 * Added support for generating OCI hook JSON file to `nvidia-ctk runtime configure` command.
 * Remove installation of OCI hook JSON from RPM package.
 * Refactored config for `nvidia-container-runtime-hook`.
+* Added a `nvidia-ctk config` command which supports setting config options using a `--set` flag.
 
 ## v1.14.0-rc.2
-
 * Fix bug causing incorrect nvidia-smi symlink to be created on WSL2 systems with multiple driver roots.
 * Remove dependency on coreutils when installing package on RPM-based systems.
 * Create ouput folders if required when running `nvidia-ctk runtime configure`

cmd/nvidia-ctk/README.md

@@ -16,6 +16,31 @@ nvidia-ctk runtime configure --set-as-default
 will ensure that the NVIDIA Container Runtime is added as the default runtime to the default container
 engine.
 
+## Configure the NVIDIA Container Toolkit
+
+The `config` command of the `nvidia-ctk` CLI allows a user to display and manipulate the NVIDIA Container Toolkit
+configuration.
+
+For example, running the following command:
+```bash
+nvidia-ctk config default
+```
+will display the default config for the detected platform.
+
+Whereas
+```bash
+nvidia-ctk config
+```
+will display the effective NVIDIA Container Toolkit config using the configured config file, and running:
+
+Individual config options can be set by specifying these are key-value pairs to the `--set` argument:
+
+```bash
+nvidia-ctk config --set nvidia-container-cli.no-cgroups=true
+```
+
+By default, all commands output to `STDOUT`, but specifying the `--output` flag writes the config to the specified file.
+
 ### Generate CDI specifications
 
 The [Container Device Interface (CDI)](https://github.com/container-orchestrated-devices/container-device-interface) provides

cmd/nvidia-ctk/config/config.go

@@ -17,7 +17,15 @@
 package config
 
 import (
+	"errors"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
 	createdefault "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/config/create-default"
+	"github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/config/flags"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/config"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
 	"github.com/urfave/cli/v2"
 )
@@ -26,6 +34,12 @@ type command struct {
 	logger logger.Interface
 }
 
+// options stores the subcommand options
+type options struct {
+	flags.Options
+	sets cli.StringSlice
+}
+
 // NewCommand constructs an config command with the specified logger
 func NewCommand(logger logger.Interface) *cli.Command {
 	c := command{
@@ -36,10 +50,42 @@ func NewCommand(logger logger.Interface) *cli.Command {
 
 // build
 func (m command) build() *cli.Command {
+	opts := options{}
+
 	// Create the 'config' command
 	c := cli.Command{
 		Name:  "config",
 		Usage: "Interact with the NVIDIA Container Toolkit configuration",
+		Action: func(ctx *cli.Context) error {
+			return run(ctx, &opts)
+		},
+	}
+
+	c.Flags = []cli.Flag{
+		&cli.StringFlag{
+			Name:        "config-file",
+			Aliases:     []string{"config", "c"},
+			Usage:       "Specify the config file to modify.",
+			Value:       config.GetConfigFilePath(),
+			Destination: &opts.Config,
+		},
+		&cli.StringSliceFlag{
+			Name:        "set",
+			Usage:       "Set a config value using the pattern key=value. If value is empty, this is equivalent to specifying the same key in unset. This flag can be specified multiple times",
+			Destination: &opts.sets,
+		},
+		&cli.BoolFlag{
+			Name:        "in-place",
+			Aliases:     []string{"i"},
+			Usage:       "Modify the config file in-place",
+			Destination: &opts.InPlace,
+		},
+		&cli.StringFlag{
+			Name:        "output",
+			Aliases:     []string{"o"},
+			Usage:       "Specify the output file to write to; If not specified, the output is written to stdout",
+			Destination: &opts.Output,
+		},
 	}
 
 	c.Subcommands = []*cli.Command{
@@ -48,3 +94,71 @@ func (m command) build() *cli.Command {
 
 	return &c
 }
+
+func run(c *cli.Context, opts *options) error {
+	cfgToml, err := config.New(
+		config.WithConfigFile(opts.Config),
+	)
+	if err != nil {
+		return fmt.Errorf("unable to create config: %v", err)
+	}
+
+	for _, set := range opts.sets.Value() {
+		key, value, err := (*configToml)(cfgToml).setFlagToKeyValue(set)
+		if err != nil {
+			return fmt.Errorf("invalid --set option %v: %w", set, err)
+		}
+		cfgToml.Set(key, value)
+	}
+
+	cfgToml.Save(os.Stdout)
+	return nil
+}
+
+type configToml config.Toml
+
+var errInvalidConfigOption = errors.New("invalid config option")
+var errInvalidFormat = errors.New("invalid format")
+
+// setFlagToKeyValue converts a --set flag to a key-value pair.
+// The set flag is of the form key[=value], with the value being optional if key refers to a
+// boolean config option.
+func (c *configToml) setFlagToKeyValue(setFlag string) (string, interface{}, error) {
+	if c == nil {
+		return "", nil, errInvalidConfigOption
+	}
+
+	setParts := strings.SplitN(setFlag, "=", 2)
+	key := setParts[0]
+
+	v := (*config.Toml)(c).Get(key)
+	if v == nil {
+		return key, nil, errInvalidConfigOption
+	}
+	switch v.(type) {
+	case bool:
+		if len(setParts) == 1 {
+			return key, true, nil
+		}
+	}
+
+	if len(setParts) != 2 {
+		return key, nil, fmt.Errorf("%w: expected key=value; got %v", errInvalidFormat, setFlag)
+	}
+
+	value := setParts[1]
+	switch vt := v.(type) {
+	case bool:
+		b, err := strconv.ParseBool(value)
+		if err != nil {
+			return key, value, fmt.Errorf("%w: %w", errInvalidFormat, err)
+		}
+		return key, b, err
+	case string:
+		return key, value, nil
+	case []string:
+		return key, strings.Split(value, ","), nil
+	default:
+		return key, nil, fmt.Errorf("unsupported type for %v (%v)", setParts, vt)
+	}
+}

cmd/nvidia-ctk/config/config_test.go

@@ -0,0 +1,173 @@
+/**
+# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package config
+
+import (
+	"testing"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/config"
+	"github.com/pelletier/go-toml"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSetFlagToKeyValue(t *testing.T) {
+	testCases := []struct {
+		description   string
+		config        map[string]interface{}
+		setFlag       string
+		expectedKey   string
+		expectedValue interface{}
+		expectedError error
+	}{
+		{
+			description:   "empty config returns an error",
+			setFlag:       "anykey=value",
+			expectedKey:   "anykey",
+			expectedError: errInvalidConfigOption,
+		},
+		{
+			description: "option not present returns an error",
+			config: map[string]interface{}{
+				"defined": "defined-value",
+			},
+			setFlag:       "undefined=new-value",
+			expectedKey:   "undefined",
+			expectedError: errInvalidConfigOption,
+		},
+		{
+			description: "boolean option assumes true",
+			config: map[string]interface{}{
+				"boolean": false,
+			},
+			setFlag:       "boolean",
+			expectedKey:   "boolean",
+			expectedValue: true,
+		},
+		{
+			description: "boolean option returns true",
+			config: map[string]interface{}{
+				"boolean": false,
+			},
+			setFlag:       "boolean=true",
+			expectedKey:   "boolean",
+			expectedValue: true,
+		},
+		{
+			description: "boolean option returns false",
+			config: map[string]interface{}{
+				"boolean": false,
+			},
+			setFlag:       "boolean=false",
+			expectedKey:   "boolean",
+			expectedValue: false,
+		},
+		{
+			description: "invalid boolean option returns error",
+			config: map[string]interface{}{
+				"boolean": false,
+			},
+			setFlag:       "boolean=something",
+			expectedKey:   "boolean",
+			expectedValue: "something",
+			expectedError: errInvalidFormat,
+		},
+		{
+			description: "string option requires value",
+			config: map[string]interface{}{
+				"string": "value",
+			},
+			setFlag:       "string",
+			expectedKey:   "string",
+			expectedValue: nil,
+			expectedError: errInvalidFormat,
+		},
+		{
+			description: "string option returns value",
+			config: map[string]interface{}{
+				"string": "value",
+			},
+			setFlag:       "string=string-value",
+			expectedKey:   "string",
+			expectedValue: "string-value",
+		},
+		{
+			description: "string option returns value with equals",
+			config: map[string]interface{}{
+				"string": "value",
+			},
+			setFlag:       "string=string-value=more",
+			expectedKey:   "string",
+			expectedValue: "string-value=more",
+		},
+		{
+			description: "string option treats bool value as string",
+			config: map[string]interface{}{
+				"string": "value",
+			},
+			setFlag:       "string=true",
+			expectedKey:   "string",
+			expectedValue: "true",
+		},
+		{
+			description: "string option treats int value as string",
+			config: map[string]interface{}{
+				"string": "value",
+			},
+			setFlag:       "string=5",
+			expectedKey:   "string",
+			expectedValue: "5",
+		},
+		{
+			description: "[]string option returns single value",
+			config: map[string]interface{}{
+				"string": []string{"value"},
+			},
+			setFlag:       "string=string-value",
+			expectedKey:   "string",
+			expectedValue: []string{"string-value"},
+		},
+		{
+			description: "[]string option returns multiple values",
+			config: map[string]interface{}{
+				"string": []string{"value"},
+			},
+			setFlag:       "string=first,second",
+			expectedKey:   "string",
+			expectedValue: []string{"first", "second"},
+		},
+		{
+			description: "[]string option returns values with equals",
+			config: map[string]interface{}{
+				"string": []string{"value"},
+			},
+			setFlag:       "string=first=1,second=2",
+			expectedKey:   "string",
+			expectedValue: []string{"first=1", "second=2"},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.description, func(t *testing.T) {
+			tree, _ := toml.TreeFromMap(tc.config)
+			cfgToml := (*config.Toml)(tree)
+			k, v, err := (*configToml)(cfgToml).setFlagToKeyValue(tc.setFlag)
+			require.ErrorIs(t, err, tc.expectedError)
+			require.EqualValues(t, tc.expectedKey, k)
+			require.EqualValues(t, tc.expectedValue, v)
+		})
+	}
+}

cmd/nvidia-ctk/config/create-default/create-default.go

@@ -18,10 +18,8 @@ package defaultsubcommand
 
 import (
 	"fmt"
-	"io"
-	"os"
-	"path/filepath"
 
+	"github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/config/flags"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/config"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
 	"github.com/urfave/cli/v2"
@@ -31,11 +29,6 @@ type command struct {
 	logger logger.Interface
 }
 
-// options stores the subcommand options
-type options struct {
-	output string
-}
-
 // NewCommand constructs a default command with the specified logger
 func NewCommand(logger logger.Interface) *cli.Command {
 	c := command{
@@ -46,7 +39,7 @@ func NewCommand(logger logger.Interface) *cli.Command {
 
 // build creates the CLI command
 func (m command) build() *cli.Command {
-	opts := options{}
+	opts := flags.Options{}
 
 	// Create the 'default' command
 	c := cli.Command{
@@ -66,24 +59,24 @@ func (m command) build() *cli.Command {
 			Name:        "output",
 			Aliases:     []string{"o"},
 			Usage:       "Specify the output file to write to; If not specified, the output is written to stdout",
-			Destination: &opts.output,
+			Destination: &opts.Output,
 		},
 	}
 
 	return &c
 }
 
-func (m command) validateFlags(c *cli.Context, opts *options) error {
+func (m command) validateFlags(c *cli.Context, opts *flags.Options) error {
-	return nil
+	return opts.Validate()
 }
 
-func (m command) run(c *cli.Context, opts *options) error {
+func (m command) run(c *cli.Context, opts *flags.Options) error {
 	cfgToml, err := config.New()
 	if err != nil {
 		return fmt.Errorf("unable to load or create config: %v", err)
 	}
 
-	if err := opts.ensureOutputFolder(); err != nil {
+	if err := opts.EnsureOutputFolder(); err != nil {
 		return fmt.Errorf("failed to create output directory: %v", err)
 	}
 	output, err := opts.CreateOutput()
@@ -99,31 +92,3 @@ func (m command) run(c *cli.Context, opts *options) error {
 
 	return nil
 }
-
-// ensureOutputFolder creates the output folder if it does not exist.
-// If the output folder is not specified (i.e. output to STDOUT), it is ignored.
-func (o options) ensureOutputFolder() error {
-	if o.output == "" {
-		return nil
-	}
-	if dir := filepath.Dir(o.output); dir != "" {
-		return os.MkdirAll(dir, 0755)
-	}
-	return nil
-}
-
-func (o options) CreateOutput() (io.WriteCloser, error) {
-	if o.output != "" {
-		return os.Create(o.output)
-	}
-
-	return nullCloser{os.Stdout}, nil
-}
-
-type nullCloser struct {
-	io.Writer
-}
-
-func (d nullCloser) Close() error {
-	return nil
-}

cmd/nvidia-ctk/config/flags/options.go

@@ -0,0 +1,71 @@
+/**
+# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package flags
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+// Options stores options for the config commands
+type Options struct {
+	Config  string
+	Output  string
+	InPlace bool
+}
+
+// Validate checks whether the options are valid.
+func (o Options) Validate() error {
+	if o.InPlace && o.Output != "" {
+		return fmt.Errorf("cannot specify both --in-place and --output")
+	}
+
+	return nil
+}
+
+// EnsureOutputFolder creates the output folder if it does not exist.
+// If the output folder is not specified (i.e. output to STDOUT), it is ignored.
+func (o Options) EnsureOutputFolder() error {
+	if o.Output == "" {
+		return nil
+	}
+	if dir := filepath.Dir(o.Output); dir != "" {
+		return os.MkdirAll(dir, 0755)
+	}
+	return nil
+}
+
+// CreateOutput creates the writer for the output.
+func (o Options) CreateOutput() (io.WriteCloser, error) {
+	if o.Output != "" {
+		return os.Create(o.Output)
+	}
+
+	return nullCloser{os.Stdout}, nil
+}
+
+// nullCloser is a writer that does nothing on Close.
+type nullCloser struct {
+	io.Writer
+}
+
+// Close is a no-op for a nullCloser.
+func (d nullCloser) Close() error {
+	return nil
+}

internal/config/toml.go

@@ -148,6 +148,21 @@ func (t Toml) format(contents []byte) ([]byte, error) {
 	return replaced, nil
 }
 
+// Delete deletes the specified key from the TOML config.
+func (t *Toml) Delete(key string) error {
+	return (*toml.Tree)(t).Delete(key)
+}
+
+// Get returns the value for the specified key.
+func (t *Toml) Get(key string) interface{} {
+	return (*toml.Tree)(t).Get(key)
+}
+
+// Set sets the specified key to the specified value in the TOML config.
+func (t *Toml) Set(key string, value interface{}) {
+	(*toml.Tree)(t).Set(key, value)
+}
+
 // commentDefaults applies the required comments for default values to the Toml.
 func (t *Toml) commentDefaults() *Toml {
 	asToml := (*toml.Tree)(t)

packaging/debian/nvidia-container-toolkit-base.postinst

@@ -4,7 +4,7 @@ set -e
 
 case "$1" in
     configure)
-        /usr/bin/nvidia-ctk --quiet config default --in-place --config=/etc/nvidia-container-runtime/config.toml
+        /usr/bin/nvidia-ctk --quiet config --config-file=/etc/nvidia-container-runtime/config.toml --in-place
     ;;
 
     abort-upgrade|abort-remove|abort-deconfigure)

packaging/rpm/SPECS/nvidia-container-toolkit.spec

@@ -59,7 +59,7 @@ rm -rf %{_localstatedir}/lib/rpm-state/nvidia-container-toolkit
 ln -sf %{_bindir}/nvidia-container-runtime-hook %{_bindir}/nvidia-container-toolkit
 
 # Generate the default config; If this file already exists no changes are made.
-%{_bindir}/nvidia-ctk --quiet config default --in-place --config=%{_sysconfdir}/nvidia-container-runtime/config.toml
+%{_bindir}/nvidia-ctk --quiet config --config-file=%{_sysconfdir}/nvidia-container-runtime/config.toml --in-place
 
 %postun
 if [ "$1" = 0 ]; then  # package is uninstalled, not upgraded