Added "kernel delete" command.

internal/app/wwctl/kernel/delete/main.go

@@ -0,0 +1,41 @@
+package delete
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/hpcng/warewulf/internal/pkg/kernel"
+	"github.com/hpcng/warewulf/internal/pkg/node"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
+	"github.com/spf13/cobra"
+)
+
+func CobraRunE(cmd *cobra.Command, args []string) error {
+
+	nodeDB, err := node.New()
+	if err != nil {
+		wwlog.Printf(wwlog.ERROR, "Could not open nodeDB: %s\n", err)
+		os.Exit(1)
+	}
+
+	nodes, _ := nodeDB.FindAllNodes()
+
+ARG_LOOP:
+	for _, arg := range args {
+		for _, n := range nodes {
+			if n.KernelVersion.Get() == arg {
+				wwlog.Printf(wwlog.ERROR, "Kernel is configured for nodes, skipping: %s\n", arg)
+				continue ARG_LOOP
+			}
+		}
+
+		err := kernel.DeleteKernel(arg)
+		if err != nil {
+			wwlog.Printf(wwlog.ERROR, "Could not delete kernel: %s\n", arg)
+		} else {
+			fmt.Printf("Kernel has been deleted: %s\n", arg)
+		}
+	}
+
+	return nil
+}

internal/app/wwctl/kernel/delete/root.go

@@ -0,0 +1,22 @@
+package delete
+
+import "github.com/spf13/cobra"
+
+var (
+	baseCmd = &cobra.Command{
+		Use:   "delete [flags] [kernel version]...",
+		Short: "Delete an imported kernel",
+		Long:  "This command will delete a kernel that has been imported into Warewulf.",
+		RunE:  CobraRunE,
+		Args:  cobra.MinimumNArgs(1),
+	}
+)
+
+func init() {
+
+}
+
+// GetRootCommand returns the root cobra.Command for the application.
+func GetCommand() *cobra.Command {
+	return baseCmd
+}

internal/app/wwctl/kernel/root.go

@@ -1,6 +1,7 @@
 package kernel
 
 import (
+	"github.com/hpcng/warewulf/internal/app/wwctl/kernel/delete"
 	"github.com/hpcng/warewulf/internal/app/wwctl/kernel/imprt"
 	"github.com/hpcng/warewulf/internal/app/wwctl/kernel/list"
 	"github.com/spf13/cobra"
@@ -18,6 +19,7 @@ var (
 func init() {
 	baseCmd.AddCommand(imprt.GetCommand())
 	baseCmd.AddCommand(list.GetCommand())
+	baseCmd.AddCommand(delete.GetCommand())
 }
 
 // GetRootCommand returns the root cobra.Command for the application.