search: graphql api to give detailed repo info

DetailedRepoInfo graphql api returns detailed repo info given repo name
repo contains its manifests info
Each manifest entry contains digest,signed, tag and layers info
Each layer info containes digest, size

Signed-off-by: Shivam Mishra <shimish2@cisco.com>

pkg/extensions/search/common/oci_layout.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	goerrors "errors"
 	"path"
+	"strconv"
 	"strings"
 	"time"
 
@@ -17,12 +18,30 @@ import (
 	"zotregistry.io/zot/pkg/storage"
 )
 
+const cosignedAnnotation = "dev.cosign.signature.baseimage"
+
 // OciLayoutInfo ...
 type OciLayoutUtils struct {
 	Log             log.Logger
 	StoreController storage.StoreController
 }
 
+type RepoInfo struct {
+	Manifests []Manifest `json:"manifests"`
+}
+
+type Manifest struct {
+	Tag      string  `json:"tag"`
+	Digest   string  `json:"digest"`
+	IsSigned bool    `json:"isSigned"`
+	Layers   []Layer `json:"layers"`
+}
+
+type Layer struct {
+	Size   string `json:"size"`
+	Digest string `json:"digest"`
+}
+
 // NewOciLayoutUtils initializes a new OciLayoutUtils object.
 func NewOciLayoutUtils(storeController storage.StoreController, log log.Logger) *OciLayoutUtils {
 	return &OciLayoutUtils{Log: log, StoreController: storeController}
@@ -183,6 +202,65 @@ func (olu OciLayoutUtils) GetImageTagsWithTimestamp(repo string) ([]TagInfo, err
 	return tagsInfo, nil
 }
 
+func (olu OciLayoutUtils) GetExpandedRepoInfo(name string) (RepoInfo, error) {
+	repo := RepoInfo{}
+
+	manifests := make([]Manifest, 0)
+
+	manifestList, err := olu.GetImageManifests(name)
+	if err != nil {
+		olu.Log.Error().Err(err).Msg("error getting image manifests")
+
+		return RepoInfo{}, err
+	}
+
+	for _, manifest := range manifestList {
+		manifestInfo := Manifest{}
+
+		manifestInfo.Digest = manifest.Digest.Encoded()
+
+		manifestInfo.IsSigned = false
+
+		tag, ok := manifest.Annotations[ispec.AnnotationRefName]
+		if !ok {
+			tag = "latest"
+		}
+
+		manifestInfo.Tag = tag
+
+		manifest, err := olu.GetImageBlobManifest(name, manifest.Digest)
+		if err != nil {
+			olu.Log.Error().Err(err).Msg("error getting image manifest blob")
+
+			return RepoInfo{}, err
+		}
+
+		layers := make([]Layer, 0)
+
+		for _, layer := range manifest.Layers {
+			layerInfo := Layer{}
+
+			layerInfo.Digest = layer.Digest.Hex
+
+			layerInfo.Size = strconv.FormatInt(layer.Size, 10)
+
+			layers = append(layers, layerInfo)
+
+			if _, ok := layer.Annotations[cosignedAnnotation]; ok {
+				manifestInfo.IsSigned = true
+			}
+		}
+
+		manifestInfo.Layers = layers
+
+		manifests = append(manifests, manifestInfo)
+	}
+
+	repo.Manifests = manifests
+
+	return repo, nil
+}
+
 func GetImageDirAndTag(imageName string) (string, string) {
 	var imageDir string