fix allow-dup flag as well

pkg/build/ci.go

@@ -139,21 +139,23 @@ func (bi *Instance) checkBuildExists() (bool, error) {
 
 	// TODO: Do we need to handle the errors more effectively?
 	existErrors := []error{}
+	foundItems := 0
 	for _, path := range gcsBuildPaths {
 		logrus.Infof("Checking if GCS build path (%s) exists", path)
 		exists, existErr := bi.objStore.PathExists(path)
 		if existErr != nil || !exists {
 			existErrors = append(existErrors, existErr)
 		}
+		foundItems++
 	}
 
 	images := release.NewImages()
 	imagesExist, imagesExistErr := images.Exists(bi.opts.Registry, version, bi.opts.Fast)
 	if imagesExistErr != nil {
 		existErrors = append(existErrors, imagesExistErr)
 	}
-
-	if imagesExist && len(existErrors) == 0 {
+	// we are expecting atleast 3 items to be found; /version folder, kubernetes.tgz and /version/bin folder
+	if imagesExist && len(existErrors) == 0 && foundItems >= 3 && !bi.opts.AllowDup {
 		logrus.Infof("Build already exists. Exiting...")
 		return true, nil
 	}

pkg/release/images.go

@@ -298,6 +298,10 @@ func (i *Images) Validate(registry, version, buildPath string) error {
 // existence of a local build directory. Used in CI builds to quickly validate
 // if a build is actually required.
 func (i *Images) Exists(registry, version string, fast bool) (bool, error) {
+	if registry == "" {
+		logrus.Info("no image registry was supplied, assuming no images are being pushed")
+		return true, nil
+	}
 	logrus.Infof("Validating image manifests in %s", registry)
 	version = i.normalizeVersion(version)