Added Init to datastructure, fixups to container interface, and --setdefault to kernel and container build

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

@@ -1,7 +1,9 @@
 package build
 
 import (
+	"fmt"
 	"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"
 	"os"
@@ -17,6 +19,31 @@ func CobraRunE(cmd *cobra.Command, args []string) error {
 		}
 	}
 
+	if SetDefault == true {
+		if len(args) != 1 {
+			wwlog.Printf(wwlog.ERROR, "Can only set default for one kernel version\n")
+		} else {
+			nodeDB, err := node.New()
+			if err != nil {
+				wwlog.Printf(wwlog.ERROR, "Could not open node configuration: %s\n", err)
+				os.Exit(1)
+			}
+
+			//TODO: Don't loop through profiles, instead have a nodeDB function that goes directly to the map
+			profiles, _ := nodeDB.FindAllProfiles()
+			for _, profile := range profiles {
+				wwlog.Printf(wwlog.DEBUG, "Looking for profile default: %s\n", profile.Id.Get())
+				if profile.Id.Get() == "default" {
+					wwlog.Printf(wwlog.DEBUG, "Found profile default, setting kernel version to: %s\n", args[0])
+					profile.KernelVersion.Set(args[0])
+					nodeDB.ProfileUpdate(profile)
+				}
+			}
+			nodeDB.Persist()
+			fmt.Printf("Set default kernel version to: %s\n", args[0])
+		}
+	}
+
 	/*
 		var nodes []node.NodeInfo
 		set := make(map[string]int)

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

@@ -12,13 +12,15 @@ var (
 		RunE:  CobraRunE,
 		Args:  cobra.MinimumNArgs(1),
 	}
-	BuildAll bool
-	ByNode   bool
+	BuildAll   bool
+	ByNode     bool
+	SetDefault bool
 )
 
 func init() {
 	baseCmd.PersistentFlags().BoolVarP(&BuildAll, "all", "a", false, "Build all overlays (runtime and system)")
 	baseCmd.PersistentFlags().BoolVarP(&ByNode, "node", "n", false, "Build overlay for a particular node(s)")
+	baseCmd.PersistentFlags().BoolVar(&SetDefault, "setdefault", false, "Set this kernel for the default profile")
 }
 
 // GetRootCommand returns the root cobra.Command for the application.