From c31427f14bb1374cb4b10e921ca05fefe94583fc Mon Sep 17 00:00:00 2001
From: Evan Lezar <elezar@nvidia.com>
Date: Wed, 19 Mar 2025 17:03:27 +0200
Subject: [PATCH] Issue warning on unsupported CDI hook

To allow for CDI hooks to be added gradually we provide a generic no-op hook
for unrecognised subcommands. This will log a warning instead of erroring out.

Signed-off-by: Evan Lezar <elezar@nvidia.com>
---
 cmd/nvidia-cdi-hook/commands/commands.go | 5 +++++
 cmd/nvidia-cdi-hook/main.go              | 5 +++++
 cmd/nvidia-ctk/hook/hook.go              | 3 +++
 3 files changed, 13 insertions(+)

diff --git a/cmd/nvidia-cdi-hook/commands/commands.go b/cmd/nvidia-cdi-hook/commands/commands.go
index 3f80ba9b..c840f939 100644
--- a/cmd/nvidia-cdi-hook/commands/commands.go
+++ b/cmd/nvidia-cdi-hook/commands/commands.go
@@ -36,3 +36,8 @@ func New(logger logger.Interface) []*cli.Command {
 		cudacompat.NewCommand(logger),
 	}
 }
+
+func WarnOnUnsupportedSubcommand(logger logger.Interface, c *cli.Context) error {
+	logger.Warningf("Unsupported hook or arguments %v", c.Args())
+	return nil
+}
diff --git a/cmd/nvidia-cdi-hook/main.go b/cmd/nvidia-cdi-hook/main.go
index d7b7c271..d5341433 100644
--- a/cmd/nvidia-cdi-hook/main.go
+++ b/cmd/nvidia-cdi-hook/main.go
@@ -51,6 +51,11 @@ func main() {
 	c.Usage = "Command to structure files for usage inside a container, called as hooks from a container runtime, defined in a CDI yaml file"
 	c.Version = info.GetVersionString()
 
+	// We add an action to the hook
+	c.Action = func(ctx *cli.Context) error {
+		return commands.WarnOnUnsupportedSubcommand(logger, ctx)
+	}
+
 	// Setup the flags for this command
 	c.Flags = []cli.Flag{
 		&cli.BoolFlag{
diff --git a/cmd/nvidia-ctk/hook/hook.go b/cmd/nvidia-ctk/hook/hook.go
index a638d2a7..f958dc79 100644
--- a/cmd/nvidia-ctk/hook/hook.go
+++ b/cmd/nvidia-ctk/hook/hook.go
@@ -41,6 +41,9 @@ func (m hookCommand) build() *cli.Command {
 	hook := cli.Command{
 		Name:  "hook",
 		Usage: "A collection of hooks that may be injected into an OCI spec",
+		Action: func(ctx *cli.Context) error {
+			return commands.WarnOnUnsupportedSubcommand(m.logger, ctx)
+		},
 	}
 
 	hook.Subcommands = commands.New(m.logger)