readded configure hostfile command

internal/pkg/configure/hostfile.go

@@ -0,0 +1,46 @@
+package configure
+
+import (
+	"os"
+	"path"
+
+	"github.com/hpcng/warewulf/internal/pkg/node"
+	"github.com/hpcng/warewulf/internal/pkg/overlay"
+	"github.com/hpcng/warewulf/internal/pkg/util"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
+	"github.com/pkg/errors"
+)
+
+/*
+Creates '/etc/hosts' from the host template.
+*/
+func Hostfile() error {
+	if !(util.IsFile(path.Join(overlay.OverlaySourceDir("host"), "/host/etc/hosts.ww"))) {
+		wwlog.Error("'the overlay template '/etc/hosts.ww' does not exists in 'host' overlay\n")
+		os.Exit(1)
+	}
+	var nodeInfo node.NodeInfo
+	tstruct := overlay.InitStruct(nodeInfo)
+	hostname, _ := os.Hostname()
+	nodeInfo.Id.Set(hostname)
+	buffer, backupFile, writeFile, err := overlay.RenderTemplateFile(
+		path.Join(overlay.OverlaySourceDir("host"), "/host/etc/hosts.ww"),
+		tstruct)
+	if err != nil {
+		wwlog.Printf(wwlog.ERROR, "%s\n", err)
+		os.Exit(1)
+	}
+	info, err := os.Stat(path.Join(overlay.OverlaySourceDir("host"), "/host/etc/hosts.ww"))
+	if err != nil {
+		wwlog.Printf(wwlog.ERROR, "%s\n", err)
+		os.Exit(1)
+	}
+
+	if writeFile {
+		err = overlay.CarefulWriteBuffer("/etc/hosts", buffer, backupFile, info.Mode())
+		if err != nil {
+			return errors.Wrap(err, "could not write file from template")
+		}
+	}
+	return nil
+}