Fixes repo parsing

Signed-off-by: Juned Memon <junaid18183@gmail.com>

internal/experimental/registry/reference.go

@@ -34,6 +34,10 @@ var (
 	referenceDelimiter = regexp.MustCompile(`[:]`)
 	errEmptyRepo       = errors.New("parsed repo was empty")
 	errTooManyColons   = errors.New("ref may only contain a single colon character (:) unless specifying a port number")
+	// ErrInvalid is returned when there is an invalid reference
+	ErrInvalid = errors.New("invalid reference")
+	// ErrHostnameRequired is returned when the hostname is required
+	ErrHostnameRequired = errors.New("hostname required")
 )
 
 type (
@@ -86,6 +90,7 @@ func (ref *Reference) FullName() string {
 
 // validate makes sure the ref meets our criteria
 func (ref *Reference) validate() error {
+
 	err := ref.validateRepo()
 	if err != nil {
 		return err
@@ -100,7 +105,15 @@ func (ref *Reference) validateRepo() error {
 	}
 	// Makes sure the repo results in a parsable URL (similar to what is done
 	// with containerd reference parsing)
-	_, err := url.Parse(ref.Repo)
+	u, err := url.Parse("dummy://" + ref.Repo)
+
+	if u.Scheme != "dummy" {
+		return ErrInvalid
+	}
+
+	if u.Host == "" {
+		return ErrHostnameRequired
+	}
 	return err
 }