load: add usage doc for load command

fix: #I1PFQX

reason: add usage doc for load command
Signed-off-by: Nyangfeiyu <yangfeiyu2@huawei.com>

cmd/cli/build.go

@@ -260,12 +260,13 @@ func parseStaticBuildOpts() (*pb.BuildStatic, error) {
 
 func runBuild(ctx context.Context, cli Cli) (string, error) {
 	var (
-		err      error
-		content  string
-		dest     string
-		isIsulad bool
-		imageID  string
-		msg      *pb.BuildResponse
+		isIsulad        bool
+		msg             *pb.BuildResponse
+		err             error
+		content         string
+		dest            string
+		imageID         string
+		imageIDFilePath string
 	)
 
 	if dest, isIsulad, err = checkAndProcessOutput(); err != nil {
@@ -277,6 +278,12 @@ func runBuild(ctx context.Context, cli Cli) (string, error) {
 	if err = encryptBuildArgs(); err != nil {
 		return "", errors.Wrap(err, "encrypt --build-arg failed")
 	}
+	imageIDFilePath, err = getAbsPath(buildOpts.imageIDFile)
+	if err != nil {
+		return "", err
+	}
+	buildOpts.imageIDFile = imageIDFilePath
+
 	buildStatic, err := parseStaticBuildOpts()
 	if err != nil {
 		return "", err
@@ -457,3 +464,18 @@ func resolveDockerfilePath() (string, error) {
 	}
 	return resolvedPath, nil
 }
+
+func getAbsPath(path string) (string, error) {
+	if path == "" {
+		return "", nil
+	}
+	if filepath.IsAbs(path) {
+		return path, nil
+	}
+	pwd, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+
+	return util.MakeAbsolute(path, pwd), nil
+}

cmd/cli/build_test.go

@@ -613,3 +613,41 @@ func TestEncryptBuildArgs(t *testing.T) {
 		})
 	}
 }
+
+func TestGetAbsPath(t *testing.T) {
+	pwd, _ := os.Getwd()
+	type args struct {
+		path string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    string
+		wantErr bool
+	}{
+		{
+			name:    "TC1 - normal case with relative path",
+			args:    args{path: "./imageID.txt"},
+			want:    filepath.Join(pwd, "imageID.txt"),
+			wantErr: false,
+		},
+		{
+			name:    "TC2 - normal case with abs path",
+			args:    args{path: filepath.Join(pwd, "imageID.txt")},
+			want:    filepath.Join(pwd, "imageID.txt"),
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := getAbsPath(tt.args.path)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("getAbsPath() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("getAbsPath() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

doc/usage.md

@@ -24,6 +24,7 @@
             * [-a, --all](#-a---all-1)
         * [Version query](#version-query)
         * [Tag an image](#tag-an-image)
+        * [Load an image](#load-an-image)
 
 <!-- vim-markdown-toc -->
 # Usage
@@ -387,3 +388,31 @@ $ sudo isula-build ctr-img images
 ----------------------------------------------  -----------  -----------------  --------------------------  ------------
 ```
 
+### Load an image
+
+We can use the `load` command to load an image from the tarfile.
+
+Usage:
+
+`isula-build ctr-img load [flags]`
+
+Currently, the following flags are supported:
+
+```bash
+Flags:
+  -i, --input string   Path to local tarball
+```
+
+Use this command as follow:
+
+```bash
+$ sudo isula-build ctr-img load -i image.tar
+Getting image source signatures
+Copying blob sha256:37841116ad3b1eeea972c75ab8bad05f48f721a7431924bc547fc91c9076c1c8
+Copying blob sha256:6eb4c21cc3fcb729a9df230ae522c1d3708ca66e5cf531713dbfa679837aa287
+Copying config sha256:76a4dd2d5d6a18323ac8d90f959c3c8562bf592e2a559bab9b462ab600e9e5fc
+Writing manifest to image destination
+Storing signatures
+Loaded image as 76a4dd2d5d6a18323ac8d90f959c3c8562bf592e2a559bab9b462ab600e9e5fc
+```
+