Core of image's duplication feature

internal/app/wwctl/container/copy/main.go

@@ -0,0 +1,48 @@
+package copy
+
+import (
+	"fmt"
+
+	"github.com/hpcng/warewulf/internal/pkg/api/routes/wwapiv1"
+	"github.com/hpcng/warewulf/internal/pkg/container"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
+	"github.com/spf13/cobra"
+)
+
+func CobraRunE(cmd *cobra.Command, args []string) (err error) {
+
+	if len(args) > 2 {
+		wwlog.Warn("cp only requires 2 arguments but you provided %d arguments. Hence, they will be ignored.", len(args))
+	}
+
+	cdp := &wwapiv1.ContainerCopyParameter{
+		ContainerSource:      args[0],
+		ContainerDestination: args[1],
+	}
+
+	if !container.DoesSourceExist(cdp.ContainerSource) {
+		wwlog.Error("Container's source doesn't exists: %s", cdp.ContainerSource)
+		return
+	}
+
+	if !container.ValidName(cdp.ContainerDestination) {
+		wwlog.Error("Container name contains illegal characters : %s", cdp.ContainerDestination)
+		return
+	}
+
+	if container.DoesSourceExist(cdp.ContainerDestination) {
+		wwlog.Error("An other container with name: %s already exists in sources.", cdp.ContainerDestination)
+		return
+	}
+
+	err = container.Duplicate(cdp.ContainerSource, cdp.ContainerDestination)
+	if err != nil {
+		err = fmt.Errorf("could not duplicate image: %s", err.Error())
+		wwlog.Error(err.Error())
+		return
+	}
+
+	wwlog.Info("Container %s successfully duplicated as %s", cdp.ContainerSource, cdp.ContainerDestination)
+	return
+
+}

internal/app/wwctl/container/copy/root.go

@@ -0,0 +1,33 @@
+package copy
+
+import (
+	"github.com/hpcng/warewulf/internal/pkg/container"
+	"github.com/spf13/cobra"
+)
+
+var (
+	baseCmd = &cobra.Command{
+		DisableFlagsInUseLine: true,
+		Use:                   "cp CONTAINER NEW_NAME",
+		Short:                 "Copy an existing container",
+		Long:                  "This command will duplicate an imported container image.",
+		RunE:                  CobraRunE,
+		Args:                  cobra.MinimumNArgs(2),
+		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+			if len(args) != 0 {
+				return nil, cobra.ShellCompDirectiveNoFileComp
+			}
+			list, _ := container.ListSources()
+			return list, cobra.ShellCompDirectiveNoFileComp
+		},
+	}
+)
+
+func init() {
+	// Nothing to do here
+}
+
+// GetRootCommand returns the root cobra.Command for the application.
+func GetCommand() *cobra.Command {
+	return baseCmd
+}