kicbase: simplify the image loading logic

This change refactors beginDownloadKicBaseImage() a bit to
achieve a more streamlined flow of logic, combining
redundant blocks.

In the special case of  podman,
it leaves image loading from cache  loading from cache unimplemented
and replaces the confusing and unhelpful message by a more helpful one.

Signed-off-by: Michael Adam <[email protected]>

Author: obnoxxx

pkg/minikube/node/cache.go

@@ -154,31 +154,33 @@ func beginDownloadKicBaseImage(g *errgroup.Group, cc *config.ClusterConfig, down
 		var err error
 		for _, img := range append([]string{baseImg}, kic.FallbackImages...) {
 
-			if driver.IsDocker(cc.Driver) && download.ImageExistsInDaemon(img) && !downloadOnly {
-				klog.Infof("%s exists in daemon, skipping load", img)
-				finalImg = img
-				return nil
-			}
+			if driver.IsDocker(cc.Driver) {
+				if download.ImageExistsInDaemon(img) {
+					klog.Infof("%s exists in daemon, skipping load", img)
+					finalImg = img
+					return nil
+				}
 
-			klog.Infof("Downloading %s to local cache", img)
-			err = download.ImageToCache(img)
-			if err == nil {
-				klog.Infof("successfully saved %s as a tarball", img)
-			}
-			if downloadOnly && err == nil {
-				return nil
-			}
+				klog.Infof("Downloading %s to local cache", img)
+				err = download.ImageToCache(img)
+				if err == nil {
+					klog.Infof("successfully saved %s as a tarball", img)
+				}
+				if downloadOnly {
+					return nil
+				}
 
-			if cc.Driver == driver.Podman {
-				return fmt.Errorf("not yet implemented, see issue #8426")
-			}
-			if driver.IsDocker(cc.Driver) && err == nil {
 				klog.Infof("Loading %s from local cache", img)
 				if finalImg, err = download.CacheToDaemon(img); err == nil {
 					klog.Infof("successfully loaded and using %s from cached tarball", img)
 					return nil
 				}
 			}
+			if cc.Driver == driver.Podman {
+				return fmt.Errorf("skipping image load via cache: not implemented for podman.  see issue #8426")
+
+			}
+
 			klog.Infof("failed to download %s, will try fallback image if available: %v", img, err)
 		}
 		// second if we failed to download any fallback image