Switch to pod template file

Author: Pieter-Jan Pintens

cmd/container-structure-test/app/cmd/test.go

@@ -96,17 +96,13 @@ func NewCmdTest(out io.Writer) *cobra.Command {
 
 func run(out io.Writer) error {
 	args = &drivers.DriverConfig{
-		Image:         opts.ImagePath,
-		Save:          opts.Save,
-		Metadata:      opts.Metadata,
-		Runtime:       opts.Runtime,
-		Platform:      opts.Platform,
-		Namespace:     opts.Namespace,
-		PodnamePrefix: opts.PodnamePrefix,
-		AllowReuse:    opts.AllowReuse,
-		Labels:        opts.Labels,
-		Annotations:   opts.Annotations,
-		NodeSelector:  opts.NodeSelector,
+		Image:       opts.ImagePath,
+		Save:        opts.Save,
+		Metadata:    opts.Metadata,
+		Runtime:     opts.Runtime,
+		Platform:    opts.Platform,
+		PodTemplate: opts.PodTemplate,
+		AllowReuse:  opts.AllowReuse,
 	}
 
 	var err error
@@ -253,12 +249,8 @@ func AddTestFlags(cmd *cobra.Command) {
 	cmd.Flags().VarP(&opts.Output, "output", "o", "output format for the test report (available format: text, json, junit)")
 	cmd.Flags().BoolVar(&opts.NoColor, "no-color", false, "no color in the output")
 	cmd.Flags().StringVar(&opts.JunitSuiteName, "junit-suite-name", "", fmt.Sprintf("name to use for the junit test suite (defaults to '%s')", output.DefaultJunitSuiteName))
-	cmd.Flags().StringVar(&opts.Namespace, "namespace", "", "namespace to use with kubernetes driver")
-	cmd.Flags().StringVar(&opts.PodnamePrefix, "podname-prefix", "", "podname prefix to use with kubernetes driver")
+	cmd.Flags().StringVar(&opts.PodTemplate, "pod-template", "", "pod template to instantiate pods from with kubernetes driver")
 	cmd.Flags().BoolVar(&opts.AllowReuse, "allow-reuse", false, "if set, reuse the running pod for multiple tests, this is a lot faster but test can interfere with each other. Use with kubernetes driver")
-	cmd.Flags().StringArrayVarP(&opts.Labels, "labels", "", []string{}, "labels for k8es resources")
-	cmd.Flags().StringArrayVarP(&opts.Annotations, "annotations", "", []string{}, "annotations for k8es resources")
-	cmd.Flags().StringArrayVarP(&opts.NodeSelector, "node-selector", "", []string{}, "node selector for k8es resources")
 	cmd.Flags().StringArrayVarP(&opts.ConfigFiles, "config", "c", []string{}, "test config files")
 	cmd.MarkFlagRequired("config")
 	cmd.Flags().StringVar(&opts.TestReport, "test-report", "", "generate test report and write it to specified file (supported format: json, junit; default: json)")

pkg/config/options.go

@@ -36,11 +36,7 @@ type StructureTestOptions struct {
 	Quiet          bool
 	Force          bool
 	NoColor        bool
+	AllowReuse     bool
 
-	Namespace     string
-	PodnamePrefix string
-	AllowReuse    bool
-	Labels        []string
-	Annotations   []string
-	NodeSelector  []string
+	PodTemplate string
 }

pkg/drivers/driver.go

@@ -39,9 +39,7 @@ type DriverConfig struct {
 	Namespace     string
 	PodnamePrefix string
 	AllowReuse    bool
-	Labels        []string
-	Annotations   []string
-	NodeSelector  []string
+	PodTemplate   string
 }
 
 type Driver interface {

pkg/drivers/k8s_driver.go

@@ -40,19 +40,33 @@ import (
 	kexec "k8s.io/client-go/util/exec"
 )
 
+// PodFromFile will read a given file with pod definition and returns a corev1.Pod
+// accordingly.
+func PodFromFile(file string) (*corev1.Pod, error) {
+	decode := scheme.Codecs.UniversalDeserializer().Decode
+	stream, err := os.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+	obj, gvk, err := decode(stream, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+	if gvk.Kind == "Pod" {
+		return obj.(*corev1.Pod), nil
+	}
+	return nil, fmt.Errorf("invalid podtemplate: %s", file)
+}
+
 type K8sDriver struct {
-	Image         string
-	Client        kubernetes.Interface
-	runOpts       unversioned.ContainerRunOptions
-	KubeConfig    *rest.Config
-	Namespace     string
-	Labels        map[string]string
-	Annotations   map[string]string
-	NodeSelector  map[string]string
-	PodnamePrefix string
-	podName       string
-	AllowReuse    bool
-	env           []unversioned.EnvVar
+	Image       string
+	Client      kubernetes.Interface
+	runOpts     unversioned.ContainerRunOptions
+	KubeConfig  *rest.Config
+	PodTemplate *corev1.Pod
+	podName     string
+	AllowReuse  bool
+	env         []unversioned.EnvVar
 }
 
 func NewK8sDriver(args DriverConfig) (Driver, error) {
@@ -82,18 +96,19 @@ func NewK8sDriver(args DriverConfig) (Driver, error) {
 		return nil, err
 	}
 
+	template, err := PodFromFile(args.PodTemplate)
+	if err != nil {
+		return nil, err
+	}
+
 	return &K8sDriver{
-		Client:        clientset,
-		Image:         args.Image,
-		runOpts:       args.RunOpts,
-		PodnamePrefix: args.PodnamePrefix,
-		Namespace:     args.Namespace,
-		Labels:        convertSliceToMap(args.Labels),
-		Annotations:   convertSliceToMap(args.Annotations),
-		NodeSelector:  convertSliceToMap(args.NodeSelector),
-		KubeConfig:    k8sConfig,
-		AllowReuse:    args.AllowReuse,
-		podName:       "",
+		Client:      clientset,
+		Image:       args.Image,
+		runOpts:     args.RunOpts,
+		PodTemplate: template,
+		KubeConfig:  k8sConfig,
+		AllowReuse:  args.AllowReuse,
+		podName:     "",
 	}, nil
 }
 
@@ -293,22 +308,15 @@ func (d *K8sDriver) Destroy() {
 	if d.podName == "" {
 		return
 	}
-	err := d.Client.CoreV1().Pods(d.Namespace).Delete(context.Background(), d.podName, metav1.DeleteOptions{})
+	err := d.Client.CoreV1().Pods(d.PodTemplate.Namespace).Delete(context.Background(), d.podName, metav1.DeleteOptions{})
 	if err != nil {
 		logrus.Warnf("Error when removing pod %s: %s", d.podName, err.Error())
 	}
 	d.podName = ""
 }
 
 func (d *K8sDriver) createPod(envVars []unversioned.EnvVar, command []string) (*corev1.Pod, error) {
-	podName := d.PodnamePrefix
-	if podName == "" {
-		podName = "cst"
-	}
-	// store the name for later reference
-	d.podName = podName + "-" + rand.String(5)
-	image := d.Image
-
+	// create env vars
 	var env []corev1.EnvVar
 	for _, envVar := range envVars {
 		env = append(env, corev1.EnvVar{
@@ -317,33 +325,28 @@ func (d *K8sDriver) createPod(envVars []unversioned.EnvVar, command []string) (*
 		})
 	}
 
-	pod := &corev1.Pod{
-		ObjectMeta: metav1.ObjectMeta{
-			Name:        d.podName,
-			Namespace:   d.Namespace,
-			Labels:      d.Labels,
-			Annotations: d.Annotations,
-		},
-		Spec: corev1.PodSpec{
-			Containers: []corev1.Container{
-				{
-					Name:            "main",
-					Image:           image,
-					Command:         command,
-					Env:             env,
-					ImagePullPolicy: corev1.PullAlways,
-				},
-			},
-			RestartPolicy: corev1.RestartPolicyNever,
-			NodeSelector:  d.NodeSelector,
+	// take the template, make a copy and overwrite some fields
+	pod := d.PodTemplate.DeepCopy()
+	pod.ObjectMeta.Name = d.podName + "-" + rand.String(5)
+	pod.Spec.Containers = []corev1.Container{
+		{
+			Name:            "main",
+			Image:           d.Image,
+			Command:         command,
+			Env:             env,
+			ImagePullPolicy: corev1.PullAlways,
 		},
 	}
+	pod.Spec.RestartPolicy = corev1.RestartPolicyNever
+
+	// store the name for later reference
+	d.podName = pod.ObjectMeta.Name
 
-	return d.Client.CoreV1().Pods(d.Namespace).Create(context.Background(), pod, metav1.CreateOptions{})
+	return d.Client.CoreV1().Pods(pod.Namespace).Create(context.Background(), pod, metav1.CreateOptions{})
 }
 
 func (d *K8sDriver) waitForPod() error {
-	watcher, err := d.Client.CoreV1().Pods(d.Namespace).Watch(context.Background(), metav1.ListOptions{
+	watcher, err := d.Client.CoreV1().Pods(d.PodTemplate.Namespace).Watch(context.Background(), metav1.ListOptions{
 		FieldSelector: "metadata.name=" + d.podName,
 	})
 	if err != nil {
@@ -370,7 +373,7 @@ func (d *K8sDriver) execInPod(command []string) (string, string, int, error) {
 	req := d.Client.CoreV1().RESTClient().Post().
 		Resource("pods").
 		Name(d.podName).
-		Namespace(d.Namespace).
+		Namespace(d.PodTemplate.Namespace).
 		SubResource("exec").
 		VersionedParams(&corev1.PodExecOptions{
 			Command:   command,