Support inspect graph driver's metadata

Signed-off-by: NWangFengTu <wangfengtu@huawei.com>

cmd/isulad_img/grpc.go

@@ -261,12 +261,12 @@ func (s *grpcImageService) ListImages(ctx context.Context, req *pb.ListImagesReq
 
 	resp := &pb.ListImagesResponse{}
 	for _, img := range images.Images {
-		respImg, err := transImageToPBImage(img)
-		if err != nil {
+		respImg, err2 := transImageToPBImage(img)
+		if err2 != nil {
 			return &pb.ListImagesResponse{
-				Errmsg: err.Error(),
+				Errmsg: err2.Error(),
 				Cc:     1,
-			}, err
+			}, err2
 		}
 
 		resp.Images = append(resp.Images, respImg)
@@ -637,6 +637,30 @@ func (s *grpcImageService) GraphdriverStatus(ctx context.Context, req *pb.Graphd
 	return resp, nil
 }
 
+// get metadata of graphdriver
+func (s *grpcImageService) GraphdriverMetadata(ctx context.Context, req *pb.GraphdriverMetadataRequest) (*pb.GraphdriverMetadataResponse, error) {
+	var err error
+
+	if req == nil || req.NameId == "" {
+		err = errors.New("Lack infomation for driver metadata")
+		return &pb.GraphdriverMetadataResponse{
+			Errmsg: err.Error(),
+			Cc:     1,
+		}, err
+	}
+
+	resp := &pb.GraphdriverMetadataResponse{}
+	resp.Metadata, resp.Name, err = storageMetadata(s.gopts, req.NameId)
+	if err != nil {
+		return &pb.GraphdriverMetadataResponse{
+			Errmsg: err.Error(),
+			Cc:     1,
+		}, err
+	}
+
+	return resp, nil
+}
+
 // login registry
 func (s *grpcImageService) Login(ctx context.Context, req *pb.LoginRequest) (*pb.LoginResponse, error) {
 	if req == nil || req.Server == "" || req.Username == "" || req.Password == "" {

cmd/isulad_img/storage_metadata.go

+// Copyright (c) Huawei Technologies Co., Ltd. 2020. All rights reserved.
+// iSulad-img licensed under the Mulan PSL v1.
+// You can use this software according to the terms and conditions of the Mulan PSL v1.
+// You may obtain a copy of Mulan PSL v1 at:
+//     http://license.coscl.org.cn/MulanPSL
+// THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR
+// PURPOSE.
+// See the Mulan PSL v1 for more details.
+// Description: iSulad image kit
+// Author: wangfengtu
+// Create: 2020-03-20
+
+package main
+
+import "fmt"
+
+func storageMetadata(gopts *globalOptions, nameID string) (metadata map[string]string, name string, err error) {
+	imageService, err := getImageService(gopts)
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to get image service: %v", err)
+	}
+
+	runtimeService := getRuntimeService("", imageService)
+	if runtimeService == nil {
+		return nil, "", fmt.Errorf("failed to get runtime service: %v", err)
+	}
+
+	layerID, err := runtimeService.GetContainerLayerID(nameID)
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to get container layer id by %v: %v", nameID, err)
+	}
+
+	store, err := getStorageStore(gopts)
+	if err != nil {
+		return nil, "", err
+	}
+
+	driver, err := store.GraphDriver()
+	if err != nil {
+		return nil, "", err
+	}
+
+	metadata, err = driver.Metadata(layerID)
+	if err != nil {
+		return nil, "", err
+	}
+
+	return metadata, driver.String(), err
+}

isula/isula_image.proto

@@ -76,6 +76,9 @@ service ImageService {
     // get status of graphdriver
     rpc GraphdriverStatus(GraphdriverStatusRequest) returns (GraphdriverStatusResponse) {}
 
+    // get metadata of graphdriver
+    rpc GraphdriverMetadata(GraphdriverMetadataRequest) returns (GraphdriverMetadataResponse) {}
+
     // login registry
     rpc Login(LoginRequest) returns (LoginResponse) {}
     // logout registry
@@ -144,6 +147,17 @@ message GraphdriverStatusResponse {
     uint32 cc = 3;
 }
 
+message GraphdriverMetadataRequest {
+    string name_id = 1;
+}
+
+message GraphdriverMetadataResponse {
+    map<string,string> metadata = 1;
+    string name = 2;
+    string errmsg = 3;
+    uint32 cc = 4;
+}
+
 message ContainerFsUsageRequest {
     string name_id = 1;
 }