Merge pull request #723 from valentinsoe/warmer-reuse-cache

Add checking image presence in cache prior to downloading it

cmd/warmer/cmd/root.go

@@ -19,6 +19,7 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"time"
 
 	"github.com/GoogleContainerTools/kaniko/pkg/cache"
 	"github.com/GoogleContainerTools/kaniko/pkg/config"
@@ -61,6 +62,8 @@ var RootCmd = &cobra.Command{
 func addKanikoOptionsFlags(cmd *cobra.Command) {
 	RootCmd.PersistentFlags().VarP(&opts.Images, "image", "i", "Image to cache. Set it repeatedly for multiple images.")
 	RootCmd.PersistentFlags().StringVarP(&opts.CacheDir, "cache-dir", "c", "/cache", "Directory of the cache.")
+	RootCmd.PersistentFlags().BoolVarP(&opts.Force, "force", "f", false, "Force cache overwriting.")
+	RootCmd.PersistentFlags().DurationVarP(&opts.CacheTTL, "cache-ttl", "", time.Hour*336, "Cache timeout in hours. Defaults to two weeks.")
 }
 
 // addHiddenFlags marks certain flags as hidden from the executor help text

pkg/cache/cache.go

@@ -114,7 +114,7 @@ func Destination(opts *config.KanikoOptions, cacheKey string) (string, error) {
 }
 
 // LocalSource retieves a source image from a local cache given cacheKey
-func LocalSource(opts *config.KanikoOptions, cacheKey string) (v1.Image, error) {
+func LocalSource(opts *config.CacheOptions, cacheKey string) (v1.Image, error) {
 	cache := opts.CacheDir
 	if cache == "" {
 		return nil, nil

pkg/cache/warm.go

@@ -50,6 +50,14 @@ func WarmCache(opts *config.WarmerOptions) error {
 			return errors.Wrap(err, fmt.Sprintf("Failed to retrieve digest: %s", image))
 		}
 		cachePath := path.Join(cacheDir, digest.String())
+
+		if !opts.Force {
+			_, err := LocalSource(&opts.CacheOptions, digest.String())
+			if err == nil {
+				continue
+			}
+		}
+
 		err = tarball.WriteToFile(cachePath, cacheRef, img)
 		if err != nil {
 			return errors.Wrap(err, fmt.Sprintf("Failed to write %s to cache", image))

pkg/config/options.go

@@ -20,16 +20,22 @@ import (
 	"time"
 )
 
+// CacheOptions are base image cache options that are set by command line arguments
+type CacheOptions struct {
+	CacheDir string
+	CacheTTL time.Duration
+}
+
 // KanikoOptions are options that are set by command line arguments
 type KanikoOptions struct {
+	CacheOptions
 	DockerfilePath          string
 	SrcContext              string
 	SnapshotMode            string
 	Bucket                  string
 	TarPath                 string
 	Target                  string
 	CacheRepo               string
-	CacheDir                string
 	DigestFile              string
 	Destinations            multiArg
 	BuildArgs               multiArg
@@ -42,13 +48,13 @@ type KanikoOptions struct {
 	NoPush                  bool
 	Cache                   bool
 	Cleanup                 bool
-	CacheTTL                time.Duration
 	InsecureRegistries      multiArg
 	SkipTLSVerifyRegistries multiArg
 }
 
 // WarmerOptions are options that are set by command line arguments to the cache warmer.
 type WarmerOptions struct {
-	Images   multiArg
-	CacheDir string
+	CacheOptions
+	Images multiArg
+	Force  bool
 }

pkg/util/image_util.go

@@ -149,5 +149,5 @@ func cachedImage(opts *config.KanikoOptions, image string) (v1.Image, error) {
 		cacheKey = d.String()
 	}
 
-	return cache.LocalSource(opts, cacheKey)
+	return cache.LocalSource(&opts.CacheOptions, cacheKey)
 }