Merge pull request #3213 from ywk253100/170914_image_size

Return image size when getting detail information of tag

docs/swagger.yaml

@@ -2586,6 +2586,9 @@ definitions:
       name:
         type: string
         description: The name of the tag.
+      size:
+        type: integer
+        description: The size of the image.
       architecture:
         type: string
         description: The architecture of the image.

src/ui/api/repository.go

@@ -54,9 +54,10 @@ type repoResp struct {
 	UpdateTime   time.Time `json:"update_time"`
 }
 
-type tag struct {
+type tagDetail struct {
 	Digest        string    `json:"digest"`
 	Name          string    `json:"name"`
+	Size          int64     `json:"size"`
 	Architecture  string    `json:"architecture"`
 	OS            string    `json:"os"`
 	DockerVersion string    `json:"docker_version"`
@@ -65,7 +66,7 @@ type tag struct {
 }
 
 type tagResp struct {
-	tag
+	tagDetail
 	Signature    *notary.Target          `json:"signature"`
 	ScanOverview *models.ImgScanOverview `json:"scan_overview,omitempty"`
 }
@@ -390,17 +391,13 @@ func assemble(client *registry.Repository, repository string,
 	for _, t := range tags {
 		item := &tagResp{}
 
-		// tag configuration
-		digest, _, cfg, err := getV2Manifest(client, t)
+		// the detail information of tag
+		tagDetail, err := getTagDetail(client, t)
 		if err != nil {
-			cfg = &tag{
-				Digest: digest,
-				Name:   t,
-			}
 			log.Errorf("failed to get v2 manifest of %s:%s: %v", repository, t, err)
 		}
-		if cfg != nil {
-			item.tag = *cfg
+		if tagDetail != nil {
+			item.tagDetail = *tagDetail
 		}
 
 		// scan overview
@@ -425,40 +422,45 @@ func assemble(client *registry.Repository, repository string,
 	return result
 }
 
-// get v2 manifest of tag, returns digest, manifest,
-// manifest config and error. The manifest config contains
-// architecture, os, author, etc.
-func getV2Manifest(client *registry.Repository, tagName string) (
-	string, *schema2.DeserializedManifest, *tag, error) {
-	digest, _, payload, err := client.PullManifest(tagName, []string{schema2.MediaTypeManifest})
-	if err != nil {
-		return "", nil, nil, err
+// getTagDetail returns the detail information for v2 manifest image
+// The information contains architecture, os, author, size, etc.
+func getTagDetail(client *registry.Repository, tag string) (*tagDetail, error) {
+	detail := &tagDetail{
+		Name: tag,
 	}
 
+	digest, _, payload, err := client.PullManifest(tag, []string{schema2.MediaTypeManifest})
+	if err != nil {
+		return detail, err
+	}
+	detail.Digest = digest
+
 	manifest := &schema2.DeserializedManifest{}
 	if err = manifest.UnmarshalJSON(payload); err != nil {
-		return digest, nil, nil, err
+		return detail, err
+	}
+
+	// size of manifest + size of layers
+	detail.Size = int64(len(payload))
+	for _, ref := range manifest.References() {
+		detail.Size += ref.Size
 	}
 
 	_, reader, err := client.PullBlob(manifest.Target().Digest.String())
 	if err != nil {
-		return digest, manifest, nil, err
+		return detail, err
 	}
 
 	configData, err := ioutil.ReadAll(reader)
 	if err != nil {
-		return digest, manifest, nil, err
+		return detail, err
 	}
 
-	config := &tag{}
-	if err = json.Unmarshal(configData, config); err != nil {
-		return digest, manifest, nil, err
+	if err = json.Unmarshal(configData, detail); err != nil {
+		return detail, err
 	}
 
-	config.Name = tagName
-	config.Digest = digest
-
-	return digest, manifest, config, nil
+	return detail, nil
 }
 
 // GetManifests returns the manifest of a tag