remove need of sql database also for GC

Author: siscia

daemon/cmd/garbage_collection.go

@@ -3,7 +3,9 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"strings"
 
+	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 
 	"github.com/cvmfs/docker-graphdriver/daemon/lib"
@@ -17,9 +19,42 @@ var garbageCollectionCmd = &cobra.Command{
 	Use:     "garbage-collection",
 	Short:   "Removes layers that are not necessary anymore",
 	Aliases: []string{"gc"},
+	Args:    cobra.ExactArgs(1),
 	Run: func(cmd *cobra.Command, args []string) {
+
 		fmt.Println("Start")
-		lib.RemoveUselessLayers()
+		repo := args[0]
+		llog := func(l *log.Entry) *log.Entry {
+			return l.WithFields(log.Fields{"action": "garbage collect",
+				"repo": repo,
+			})
+		}
+
+		manifestToRemove, err := lib.FindImageToGarbageCollect(repo)
+		if err != nil {
+			llog(lib.LogE(err)).Warning(
+				"Error in finding the image to remove from the scheduler, goin on...")
+		}
+		var images2layers map[string][]string
+
+		for _, manifest := range manifestToRemove {
+			digest := strings.Split(manifest.Config.Digest, ":")[1]
+			for _, layerStruct := range manifest.Layers {
+				layerName := strings.Split(layerStruct.Digest, ":")[1]
+				images2layers[digest] = append(images2layers[digest], layerName)
+			}
+		}
+
+		for image, layers := range images2layers {
+			for _, layer := range layers {
+				err = lib.GarbageCollectSingleLayer(repo, image, layer)
+				if err != nil {
+					llog(lib.LogE(err)).Warning(
+						"Error in removing a single layer from the repository, going on...")
+				}
+			}
+		}
+
 		os.Exit(0)
 	},
 }