@@ -1,6 +1,7 @@

 package docker

 import (

+	"encoding/json"

 	"fmt"

 	"io"

 	"io/ioutil"

@@ -300,3 +301,26 @@ func (graph *Graph) Heads() (map[string]*Image, error) {

 func (graph *Graph) imageRoot(id string) string {

 	return path.Join(graph.Root, id)

 }

+

+func (graph *Graph) getStoredChecksums() (map[string]string, error) {

+	checksums := make(map[string]string)

+	// FIXME: Store the checksum in memory

+

+	if checksumDict, err := ioutil.ReadFile(path.Join(graph.Root, "checksums")); err == nil {

+		if err := json.Unmarshal(checksumDict, &checksums); err != nil {

+			return nil, err

+		}

+	}

+	return checksums, nil

+}

+

+func (graph *Graph) storeChecksums(checksums map[string]string) error {

+	checksumJson, err := json.Marshal(checksums)

+	if err != nil {

+		return err

+	}

+	if err := ioutil.WriteFile(path.Join(graph.Root, "checksums"), checksumJson, 0600); err != nil {

+		return err

+	}

+	return nil

+}

@@ -295,16 +295,12 @@ func (img *Image) Checksum() (string, error) {

 		return "", err

 	}

-	checksumDictPth := path.Join(root, "..", "..", "checksums")

-	checksums := make(map[string]string)

-

-	if checksumDict, err := ioutil.ReadFile(checksumDictPth); err == nil {

-		if err := json.Unmarshal(checksumDict, &checksums); err != nil {

-			return "", err

-		}

-		if checksum, ok := checksums[img.Id]; ok {

-			return checksum, nil

-		}

+	checksums, err := img.graph.getStoredChecksums()

+	if err != nil {

+		return "", err

+	}

+	if checksum, ok := checksums[img.Id]; ok {

+		return checksum, nil

 	}

 	layer, err := img.layer()

@@ -343,24 +339,23 @@ func (img *Image) Checksum() (string, error) {

 	if _, err := io.Copy(h, layerData); err != nil {

 		return "", err

 	}

-

 	hash := "sha256:" + hex.EncodeToString(h.Sum(nil))

-	checksums[img.Id] = hash

 	// Reload the json file to make sure not to overwrite faster sums

 	img.graph.lockSumFile.Lock()

 	defer img.graph.lockSumFile.Unlock()

-	if checksumDict, err := ioutil.ReadFile(checksumDictPth); err == nil {

-		if err := json.Unmarshal(checksumDict, &checksums); err != nil {

-			return "", err

-		}

-	}

-	checksumJson, err := json.Marshal(checksums)

+

+	checksums, err = img.graph.getStoredChecksums()

 	if err != nil {

-		return hash, err

+		return "", err

 	}

-	if err := ioutil.WriteFile(checksumDictPth, checksumJson, 0600); err != nil {

+

+	checksums[img.Id] = hash

+

+	// Dump the checksums to disc

+	if err := img.graph.storeChecksums(checksums); err != nil {

 		return hash, err

 	}

+

 	return hash, nil

 }

@@ -578,6 +578,24 @@ func (graph *Graph) PushRepository(stdout io.Writer, remote string, localRepo Re

 	return filteredRepo, nil

 }

+// Retrieve the checksum of an image

+// Priority:

+// - Check on the stored checksums

+// - Check if the archive is exists, if it does not, ask the registry

+// - If the archive does exists, process the checksum from it

+// - If the archive does not exists and not found on registry, process checksum from layer

+func (graph *Graph) getChecksum(imageId string) (string, error) {

+	img, err := graph.Get(imageId)

+	if err != nil {

+		return "", err

+	}

+	checksum, err := img.Checksum()

+	if err != nil {

+		return "", err

+	}

+	return checksum, nil

+}

+

 type ImgListJson struct {

 	Id       string `json:"id"`

 	Checksum string `json:"checksum,omitempty"`

@@ -592,7 +610,14 @@ func (graph *Graph) PushRepository(stdout io.Writer, remote string, localRepo Re

 	var imgList []*ImgListJson

 	for _, id := range localRepo {

-		imgList = append(imgList, &ImgListJson{Id: id})

+		checksum, err := graph.getChecksum(id)

+		if err != nil {

+			return err

+		}

+		imgList = append(imgList, &ImgListJson{

+			Id:       id,

+			Checksum: checksum,

+		})

 	}

 	imgListJson, err := json.Marshal(imgList)

@@ -666,21 +691,6 @@ func (graph *Graph) PushRepository(stdout io.Writer, remote string, localRepo Re

 		}

 	}

-	for _, elem := range imgList {

-		img, err := graph.Get(elem.Id)

-		if err != nil {

-			return err

-		}

-		if elem.Checksum, err = img.Checksum(); err != nil {

-			return err

-		}

-	}

-	imgListJson, err = json.Marshal(imgList)

-	if err != nil {

-		return err

-	}

-	Debugf("json sent: %s\n", imgListJson)

-

 	req2, err := http.NewRequest("PUT", INDEX_ENDPOINT+"/repositories/"+remote+"/images", bytes.NewReader(imgListJson))

 	if err != nil {

 		return err