executor: add --label flag

Signed-off-by: Yoan Blanc <yoan@dosimple.ch>

integration/integration_test.go

@@ -309,6 +309,49 @@ func TestBuildViaRegistryMirror(t *testing.T) {
 	checkContainerDiffOutput(t, diff, expected)
 }
 
+func TestBuildWithLabels(t *testing.T) {
+	repo := getGitRepo()
+	dockerfile := "integration/dockerfiles/Dockerfile_test_label"
+
+	testLabel := "mylabel=myvalue"
+
+	// Build with docker
+	dockerImage := GetDockerImage(config.imageRepo, "Dockerfile_test_label:mylabel")
+	dockerCmd := exec.Command("docker",
+		append([]string{"build",
+			"-t", dockerImage,
+			"-f", dockerfile,
+			"--label", testLabel,
+			repo})...)
+	out, err := RunCommandWithoutTest(dockerCmd)
+	if err != nil {
+		t.Errorf("Failed to build image %s with docker command %q: %s %s", dockerImage, dockerCmd.Args, err, string(out))
+	}
+
+	// Build with kaniko
+	kanikoImage := GetKanikoImage(config.imageRepo, "Dockerfile_test_label:mylabel")
+	dockerRunFlags := []string{"run", "--net=host"}
+	dockerRunFlags = addServiceAccountFlags(dockerRunFlags, config.serviceAccount)
+	dockerRunFlags = append(dockerRunFlags, ExecutorImage,
+		"-f", dockerfile,
+		"-d", kanikoImage,
+		"--label", testLabel,
+		"-c", fmt.Sprintf("git://%s", repo),
+	)
+
+	kanikoCmd := exec.Command("docker", dockerRunFlags...)
+
+	out, err = RunCommandWithoutTest(kanikoCmd)
+	if err != nil {
+		t.Errorf("Failed to build image %s with kaniko command %q: %v %s", dockerImage, kanikoCmd.Args, err, string(out))
+	}
+
+	diff := containerDiff(t, daemonPrefix+dockerImage, kanikoImage, "--no-cache")
+
+	expected := fmt.Sprintf(emptyContainerDiff, dockerImage, kanikoImage, dockerImage, kanikoImage)
+	checkContainerDiffOutput(t, diff, expected)
+}
+
 func TestLayers(t *testing.T) {
 	offset := map[string]int{
 		"Dockerfile_test_add":     12,