feat: runtime manager

rtmanager/internal/service/patchruntime/semver.go

@@ -0,0 +1,52 @@
+package patchruntime
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/distribution/reference"
+	"golang.org/x/mod/semver"
+)
+
+// errImageRefNoTag reports that an image reference does not declare a
+// tag. The patch service maps it to `image_ref_not_semver` because a
+// digest-only or tagless reference cannot carry a semver-comparable
+// version.
+var errImageRefNoTag = errors.New("image reference is missing a tag")
+
+// extractSemverTag returns the canonical semver string ("v1.4.7") for
+// imageRef, ready to feed into golang.org/x/mod/semver. The leading "v"
+// is added when the underlying tag omits it.
+//
+// Errors returned by this function are pre-formatted for inclusion in
+// the patch service's `image_ref_not_semver` failure message.
+func extractSemverTag(imageRef string) (string, error) {
+	parsed, err := reference.ParseNormalizedNamed(imageRef)
+	if err != nil {
+		return "", fmt.Errorf("parse image reference %q: %w", imageRef, err)
+	}
+	tagged, ok := parsed.(reference.NamedTagged)
+	if !ok {
+		return "", fmt.Errorf("%w: %q", errImageRefNoTag, imageRef)
+	}
+	tag := strings.TrimSpace(tagged.Tag())
+	if tag == "" {
+		return "", fmt.Errorf("%w: %q", errImageRefNoTag, imageRef)
+	}
+	candidate := tag
+	if !strings.HasPrefix(candidate, "v") {
+		candidate = "v" + candidate
+	}
+	if !semver.IsValid(candidate) {
+		return "", fmt.Errorf("tag %q on image reference %q is not a valid semver", tag, imageRef)
+	}
+	return candidate, nil
+}
+
+// samePatchSeries reports whether two canonical semver strings (with
+// the leading "v") share their major and minor components. The third
+// component (patch) and any pre-release / build metadata are ignored.
+func samePatchSeries(currentSemver, newSemver string) bool {
+	return semver.MajorMinor(currentSemver) == semver.MajorMinor(newSemver)
+}