Merge pull request #452 from sharifelgamal/cache-fix

Create cache directory if it doesn't already exist

cmd/warmer/cmd/root.go

@@ -52,6 +52,12 @@ var RootCmd = &cobra.Command{
 		return nil
 	},
 	Run: func(cmd *cobra.Command, args []string) {
+		if _, err := os.Stat(opts.CacheDir); os.IsNotExist(err) {
+			err = os.MkdirAll(opts.CacheDir, 0755)
+			if err != nil {
+				exit(errors.Wrap(err, "Failed to create cache directory"))
+			}
+		}
 		if err := cache.WarmCache(opts); err != nil {
 			exit(errors.Wrap(err, "Failed warming cache"))
 		}

pkg/cache/cache.go

@@ -88,7 +88,7 @@ func (rc *RegistryCache) RetrieveLayer(ck string) (v1.Image, error) {
 	// Layer is stale, rebuild it.
 	if expiry.Before(time.Now()) {
 		logrus.Infof("Cache entry expired: %s", cache)
-		return nil, errors.New(fmt.Sprintf("Cache entry expired: %s", cache))
+		return nil, fmt.Errorf("Cache entry expired: %s", cache)
 	}
 
 	// Force the manifest to be populated

pkg/cache/warm.go

@@ -29,6 +29,7 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+// WarmCache populates the cache
 func WarmCache(opts *config.WarmerOptions) error {
 	cacheDir := opts.CacheDir
 	images := opts.Images
@@ -41,7 +42,7 @@ func WarmCache(opts *config.WarmerOptions) error {
 			return errors.Wrap(err, fmt.Sprintf("Failed to verify image name: %s", image))
 		}
 		img, err := remote.Image(cacheRef)
-		if err != nil {
+		if err != nil || img == nil {
 			return errors.Wrap(err, fmt.Sprintf("Failed to retrieve image: %s", image))
 		}