Entry metadata field

internal/provider/common.go

@@ -2,21 +2,29 @@ package provider
 
 import (
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 
 	"github.com/containerd/containerd/platforms"
 	"github.com/crazy-max/diun/v4/internal/model"
 	"github.com/crazy-max/diun/v4/pkg/registry"
+	"github.com/pkg/errors"
+)
+
+var (
+	metadataKeyChars  = `a-zA-Z0-9_`
+	metadataKeyRegexp = regexp.MustCompile(`^[` + metadataKeyChars + `]+$`)
 )
 
 // ValidateImage returns a standard image through Docker labels
-func ValidateImage(image string, labels map[string]string, watchByDef bool) (img model.Image, err error) {
+func ValidateImage(image string, metadata, labels map[string]string, watchByDef bool) (img model.Image, err error) {
 	if i := strings.Index(image, "@sha256:"); i > 0 {
 		image = image[:i]
 	}
 	img = model.Image{
 		Name:     image,
+		Metadata: metadata,
 		NotifyOn: model.NotifyOnDefaults,
 		SortTags: registry.SortTagReverse,
 	}
@@ -34,14 +42,14 @@ func ValidateImage(image string, labels map[string]string, watchByDef bool) (img
 	}
 
 	for key, value := range labels {
-		switch key {
-		case "diun.regopt":
+		switch {
+		case key == "diun.regopt":
 			img.RegOpt = value
-		case "diun.watch_repo":
+		case key == "diun.watch_repo":
 			if img.WatchRepo, err = strconv.ParseBool(value); err != nil {
 				return img, fmt.Errorf("cannot parse %s value of label %s", value, key)
 			}
-		case "diun.notify_on":
+		case key == "diun.notify_on":
 			if len(value) == 0 {
 				break
 			}
@@ -53,7 +61,7 @@ func ValidateImage(image string, labels map[string]string, watchByDef bool) (img
 				}
 				img.NotifyOn = append(img.NotifyOn, notifyOn)
 			}
-		case "diun.sort_tags":
+		case key == "diun.sort_tags":
 			if value == "" {
 				break
 			}
@@ -62,19 +70,19 @@ func ValidateImage(image string, labels map[string]string, watchByDef bool) (img
 				return img, fmt.Errorf("unknown sort tags type %q", value)
 			}
 			img.SortTags = sortTags
-		case "diun.max_tags":
+		case key == "diun.max_tags":
 			if img.MaxTags, err = strconv.Atoi(value); err != nil {
 				return img, fmt.Errorf("cannot parse %s value of label %s", value, key)
 			}
-		case "diun.include_tags":
+		case key == "diun.include_tags":
 			img.IncludeTags = strings.Split(value, ";")
-		case "diun.exclude_tags":
+		case key == "diun.exclude_tags":
 			img.ExcludeTags = strings.Split(value, ";")
-		case "diun.hub_tpl":
+		case key == "diun.hub_tpl":
 			img.HubTpl = value
-		case "diun.hub_link":
+		case key == "diun.hub_link":
 			img.HubLink = value
-		case "diun.platform":
+		case key == "diun.platform":
 			platform, err := platforms.Parse(value)
 			if err != nil {
 				return img, fmt.Errorf("cannot parse %s platform of label %s", value, key)
@@ -84,8 +92,27 @@ func ValidateImage(image string, labels map[string]string, watchByDef bool) (img
 				Arch:    platform.Architecture,
 				Variant: platform.Variant,
 			}
+		case strings.HasPrefix(key, "diun.metadata."):
+			mkey := strings.TrimPrefix(key, "diun.metadata.")
+			if len(mkey) == 0 || len(value) == 0 {
+				break
+			}
+			if err := validateMetadataKey(mkey); err != nil {
+				return img, errors.Wrapf(err, "invalid metadata key %q", mkey)
+			}
+			if img.Metadata == nil {
+				img.Metadata = map[string]string{}
+			}
+			img.Metadata[mkey] = value
 		}
 	}
 
 	return img, nil
 }
+
+func validateMetadataKey(key string) error {
+	if !metadataKeyRegexp.MatchString(key) {
+		return errors.Errorf("only %q are allowed", metadataKeyChars)
+	}
+	return nil
+}