Add a new OpenAPI v3 REST API to warewulfd at /api

Co-authored-by: jason yang <jasonyangshadow@gmail.com>

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

internal/pkg/image/config.go

@@ -31,3 +31,7 @@ func ImageParentDir() string {
 func ImageFile(name string) string {
 	return path.Join(ImageParentDir(), name+".img")
 }
+
+func CompressedImageFile(name string) string {
+	return ImageFile(name) + ".gz"
+}

internal/pkg/image/util.go

@@ -3,6 +3,7 @@ package image
 import (
 	"os"
 	"path/filepath"
+	"time"
 
 	"github.com/pkg/errors"
 
@@ -114,3 +115,27 @@ func DeleteImage(name string) error {
 func IsWriteAble(name string) bool {
 	return !util.IsFile(filepath.Join(SourceDir(name), "readonly"))
 }
+
+func ImageSize(name string) int {
+	if img, err := os.Stat(ImageFile(name)); err == nil {
+		return int(img.Size())
+	} else {
+		return 0
+	}
+}
+
+func ImageModTime(name string) time.Time {
+	if img, err := os.Stat(ImageFile(name)); err == nil {
+		return img.ModTime()
+	} else {
+		return time.Time{}
+	}
+}
+
+func CompressedImageSize(name string) int {
+	if img, err := os.Stat(CompressedImageFile(name)); err == nil {
+		return int(img.Size())
+	} else {
+		return 0
+	}
+}