Merge pull request containers#12440 from umohnani8/cm

Add support for configmap volumes to play kube

pkg/domain/infra/abi/play.go

@@ -239,27 +239,6 @@ func (ic *ContainerEngine) playKubePod(ctx context.Context, podName string, podY
 		return nil, err
 	}
 	podSpec := entities.PodSpec{PodSpecGen: *p}
-	volumes, err := kube.InitializeVolumes(podYAML.Spec.Volumes)
-	if err != nil {
-		return nil, err
-	}
-
-	seccompPaths, err := kube.InitializeSeccompPaths(podYAML.ObjectMeta.Annotations, options.SeccompProfileRoot)
-	if err != nil {
-		return nil, err
-	}
-
-	var ctrRestartPolicy string
-	switch podYAML.Spec.RestartPolicy {
-	case v1.RestartPolicyAlways:
-		ctrRestartPolicy = define.RestartPolicyAlways
-	case v1.RestartPolicyOnFailure:
-		ctrRestartPolicy = define.RestartPolicyOnFailure
-	case v1.RestartPolicyNever:
-		ctrRestartPolicy = define.RestartPolicyNo
-	default: // Default to Always
-		ctrRestartPolicy = define.RestartPolicyAlways
-	}
 
 	configMapIndex := make(map[string]struct{})
 	for _, configMap := range configMaps {
@@ -284,6 +263,56 @@ func (ic *ContainerEngine) playKubePod(ctx context.Context, podName string, podY
 		configMaps = append(configMaps, cm)
 	}
 
+	volumes, err := kube.InitializeVolumes(podYAML.Spec.Volumes, configMaps)
+	if err != nil {
+		return nil, err
+	}
+
+	// Go through the volumes and create a podman volume for all volumes that have been
+	// defined by a configmap
+	for _, v := range volumes {
+		if v.Type == kube.KubeVolumeTypeConfigMap && !v.Optional {
+			vol, err := ic.Libpod.NewVolume(ctx, libpod.WithVolumeName(v.Source))
+			if err != nil {
+				return nil, errors.Wrapf(err, "cannot create a local volume for volume from configmap %q", v.Source)
+			}
+			mountPoint, err := vol.MountPoint()
+			if err != nil || mountPoint == "" {
+				return nil, errors.Wrapf(err, "unable to get mountpoint of volume %q", vol.Name())
+			}
+			// Create files and add data to the volume mountpoint based on the Items in the volume
+			for k, v := range v.Items {
+				dataPath := filepath.Join(mountPoint, k)
+				f, err := os.Create(dataPath)
+				if err != nil {
+					return nil, errors.Wrapf(err, "cannot create file %q at volume mountpoint %q", k, mountPoint)
+				}
+				defer f.Close()
+				_, err = f.WriteString(v)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+	}
+
+	seccompPaths, err := kube.InitializeSeccompPaths(podYAML.ObjectMeta.Annotations, options.SeccompProfileRoot)
+	if err != nil {
+		return nil, err
+	}
+
+	var ctrRestartPolicy string
+	switch podYAML.Spec.RestartPolicy {
+	case v1.RestartPolicyAlways:
+		ctrRestartPolicy = define.RestartPolicyAlways
+	case v1.RestartPolicyOnFailure:
+		ctrRestartPolicy = define.RestartPolicyOnFailure
+	case v1.RestartPolicyNever:
+		ctrRestartPolicy = define.RestartPolicyNo
+	default: // Default to Always
+		ctrRestartPolicy = define.RestartPolicyAlways
+	}
+
 	if podOpt.Infra {
 		infraImage := util.DefaultContainerConfig().Engine.InfraImage
 		infraOptions := entities.NewInfraContainerCreateOptions()

pkg/specgen/generate/kube/kube.go

@@ -310,6 +310,11 @@ func ToSpecGen(ctx context.Context, opts *CtrSpecGenOptions) (*specgen.SpecGener
 		if !exists {
 			return nil, errors.Errorf("Volume mount %s specified for container but not configured in volumes", volume.Name)
 		}
+		// Skip if the volume is optional. This means that a configmap for a configmap volume was not found but it was
+		// optional so we can move on without throwing an error
+		if exists && volumeSource.Optional {
+			continue
+		}
 
 		dest, options, err := parseMountPath(volume.MountPath, volume.ReadOnly)
 		if err != nil {
@@ -341,6 +346,13 @@ func ToSpecGen(ctx context.Context, opts *CtrSpecGenOptions) (*specgen.SpecGener
 				Options: options,
 			}
 			s.Volumes = append(s.Volumes, &namedVolume)
+		case KubeVolumeTypeConfigMap:
+			cmVolume := specgen.NamedVolume{
+				Dest:    volume.MountPath,
+				Name:    volumeSource.Source,
+				Options: options,
+			}
+			s.Volumes = append(s.Volumes, &cmVolume)
 		default:
 			return nil, errors.Errorf("Unsupported volume source type")
 		}

pkg/specgen/generate/kube/volume.go

@@ -23,6 +23,7 @@ type KubeVolumeType int
 const (
 	KubeVolumeTypeBindMount KubeVolumeType = iota
 	KubeVolumeTypeNamed     KubeVolumeType = iota
+	KubeVolumeTypeConfigMap KubeVolumeType = iota
 )
 
 // nolint:golint
@@ -31,6 +32,14 @@ type KubeVolume struct {
 	Type KubeVolumeType
 	// Path for bind mount or volume name for named volume
 	Source string
+	// Items to add to a named volume created where the key is the file name and the value is the data
+	// This is only used when there are volumes in the yaml that refer to a configmap
+	// Example: if configmap has data "SPECIAL_LEVEL: very" then the file name is "SPECIAL_LEVEL" and the
+	// data in that file is "very".
+	Items map[string]string
+	// If the volume is optional, we can move on if it is not found
+	// Only used when there are volumes in a yaml that refer to a configmap
+	Optional bool
 }
 
 // Create a KubeVolume from an HostPathVolumeSource
@@ -98,23 +107,64 @@ func VolumeFromPersistentVolumeClaim(claim *v1.PersistentVolumeClaimVolumeSource
 	}, nil
 }
 
+func VolumeFromConfigMap(configMapVolumeSource *v1.ConfigMapVolumeSource, configMaps []v1.ConfigMap) (*KubeVolume, error) {
+	var configMap *v1.ConfigMap
+	kv := &KubeVolume{Type: KubeVolumeTypeConfigMap, Items: map[string]string{}}
+	for _, cm := range configMaps {
+		if cm.Name == configMapVolumeSource.Name {
+			matchedCM := cm
+			// Set the source to the config map name
+			kv.Source = cm.Name
+			configMap = &matchedCM
+			break
+		}
+	}
+
+	if configMap == nil {
+		// If the volumeSource was optional, move on even if a matching configmap wasn't found
+		if *configMapVolumeSource.Optional {
+			kv.Source = configMapVolumeSource.Name
+			kv.Optional = *configMapVolumeSource.Optional
+			return kv, nil
+		}
+		return nil, errors.Errorf("no such ConfigMap %q", configMapVolumeSource.Name)
+	}
+
+	// If there are Items specified in the volumeSource, that overwrites the Data from the configmap
+	if len(configMapVolumeSource.Items) > 0 {
+		for _, item := range configMapVolumeSource.Items {
+			if val, ok := configMap.Data[item.Key]; ok {
+				kv.Items[item.Path] = val
+			}
+		}
+	} else {
+		for k, v := range configMap.Data {
+			kv.Items[k] = v
+		}
+	}
+	return kv, nil
+}
+
 // Create a KubeVolume from one of the supported VolumeSource
-func VolumeFromSource(volumeSource v1.VolumeSource) (*KubeVolume, error) {
-	if volumeSource.HostPath != nil {
+func VolumeFromSource(volumeSource v1.VolumeSource, configMaps []v1.ConfigMap) (*KubeVolume, error) {
+	switch {
+	case volumeSource.HostPath != nil:
 		return VolumeFromHostPath(volumeSource.HostPath)
-	} else if volumeSource.PersistentVolumeClaim != nil {
+	case volumeSource.PersistentVolumeClaim != nil:
 		return VolumeFromPersistentVolumeClaim(volumeSource.PersistentVolumeClaim)
-	} else {
-		return nil, errors.Errorf("HostPath and PersistentVolumeClaim are currently the only supported VolumeSource")
+	case volumeSource.ConfigMap != nil:
+		return VolumeFromConfigMap(volumeSource.ConfigMap, configMaps)
+	default:
+		return nil, errors.Errorf("HostPath, ConfigMap, and PersistentVolumeClaim are currently the only supported VolumeSource")
 	}
 }
 
 // Create a map of volume name to KubeVolume
-func InitializeVolumes(specVolumes []v1.Volume) (map[string]*KubeVolume, error) {
+func InitializeVolumes(specVolumes []v1.Volume, configMaps []v1.ConfigMap) (map[string]*KubeVolume, error) {
 	volumes := make(map[string]*KubeVolume)
 
 	for _, specVolume := range specVolumes {
-		volume, err := VolumeFromSource(specVolume.VolumeSource)
+		volume, err := VolumeFromSource(specVolume.VolumeSource, configMaps)
 		if err != nil {
 			return nil, errors.Wrapf(err, "failed to create volume %q", specVolume.Name)
 		}

test/e2e/play_kube_test.go

@@ -379,6 +379,18 @@ spec:
     {{- if (eq .VolumeType "PersistentVolumeClaim") }}
     persistentVolumeClaim:
       claimName: {{ .PersistentVolumeClaim.ClaimName }}
+    {{- end }}
+	{{- if (eq .VolumeType "ConfigMap") }}
+    configMap:
+      name: {{ .ConfigMap.Name }}
+      optional: {{ .ConfigMap.Optional }}
+      {{- with .ConfigMap.Items }}
+      items:
+      {{- range . }}
+        - key: {{ .key }}
+          path: {{ .path }}
+    {{- end }}
+    {{- end }}
     {{- end }}
   {{ end }}
 {{ end }}
@@ -619,14 +631,14 @@ func createSecret(podmanTest *PodmanTestIntegration, name string, value []byte)
 	Expect(secret).Should(Exit(0))
 }
 
-// ConfigMap describes the options a kube yaml can be configured at configmap level
-type ConfigMap struct {
+// CM describes the options a kube yaml can be configured at configmap level
+type CM struct {
 	Name string
 	Data map[string]string
 }
 
-func getConfigMap(options ...configMapOption) *ConfigMap {
-	cm := ConfigMap{
+func getConfigMap(options ...configMapOption) *CM {
+	cm := CM{
 		Name: defaultConfigMapName,
 		Data: map[string]string{},
 	}
@@ -638,16 +650,16 @@ func getConfigMap(options ...configMapOption) *ConfigMap {
 	return &cm
 }
 
-type configMapOption func(*ConfigMap)
+type configMapOption func(*CM)
 
 func withConfigMapName(name string) configMapOption {
-	return func(configmap *ConfigMap) {
+	return func(configmap *CM) {
 		configmap.Name = name
 	}
 }
 
 func withConfigMapData(k, v string) configMapOption {
-	return func(configmap *ConfigMap) {
+	return func(configmap *CM) {
 		configmap.Data[k] = v
 	}
 }
@@ -1047,11 +1059,18 @@ type PersistentVolumeClaim struct {
 	ClaimName string
 }
 
+type ConfigMap struct {
+	Name     string
+	Items    []map[string]string
+	Optional bool
+}
+
 type Volume struct {
 	VolumeType string
 	Name       string
 	HostPath
 	PersistentVolumeClaim
+	ConfigMap
 }
 
 // getHostPathVolume takes a type and a location for a HostPath
@@ -1079,6 +1098,20 @@ func getPersistentVolumeClaimVolume(vName string) *Volume {
 	}
 }
 
+// getConfigMap returns a new ConfigMap Volume given the name and items
+// of the ConfigMap.
+func getConfigMapVolume(vName string, items []map[string]string, optional bool) *Volume {
+	return &Volume{
+		VolumeType: "ConfigMap",
+		Name:       defaultVolName,
+		ConfigMap: ConfigMap{
+			Name:     vName,
+			Items:    items,
+			Optional: optional,
+		},
+	}
+}
+
 type Env struct {
 	Name      string
 	Value     string
@@ -2311,6 +2344,75 @@ VOLUME %s`, ALPINE, hostPathDir+"/")
 		Expect(inspect.OutputToString()).To(Equal(correct))
 	})
 
+	It("podman play kube ConfigMap volume with no items", func() {
+		volumeName := "cmVol"
+		cm := getConfigMap(withConfigMapName(volumeName), withConfigMapData("FOO", "foobar"))
+		cmYaml, err := getKubeYaml("configmap", cm)
+		Expect(err).To(BeNil())
+
+		ctr := getCtr(withVolumeMount("/test", false), withImage(BB))
+		pod := getPod(withVolume(getConfigMapVolume(volumeName, []map[string]string{}, false)), withCtr(ctr))
+		podYaml, err := getKubeYaml("pod", pod)
+		Expect(err).To(BeNil())
+		yamls := []string{cmYaml, podYaml}
+		err = generateMultiDocKubeYaml(yamls, kubeYaml)
+		Expect(err).To(BeNil())
+
+		kube := podmanTest.Podman([]string{"play", "kube", kubeYaml})
+		kube.WaitWithDefaultTimeout()
+		Expect(kube).Should(Exit(0))
+
+		cmData := podmanTest.Podman([]string{"exec", getCtrNameInPod(pod), "cat", "/test/FOO"})
+		cmData.WaitWithDefaultTimeout()
+		Expect(cmData).Should(Exit(0))
+		Expect(cmData.OutputToString()).To(Equal("foobar"))
+	})
+
+	It("podman play kube ConfigMap volume with items", func() {
+		volumeName := "cmVol"
+		cm := getConfigMap(withConfigMapName(volumeName), withConfigMapData("FOO", "foobar"))
+		cmYaml, err := getKubeYaml("configmap", cm)
+		Expect(err).To(BeNil())
+		volumeContents := []map[string]string{{
+			"key":  "FOO",
+			"path": "BAR",
+		}}
+
+		ctr := getCtr(withVolumeMount("/test", false), withImage(BB))
+		pod := getPod(withVolume(getConfigMapVolume(volumeName, volumeContents, false)), withCtr(ctr))
+		podYaml, err := getKubeYaml("pod", pod)
+		Expect(err).To(BeNil())
+		yamls := []string{cmYaml, podYaml}
+		err = generateMultiDocKubeYaml(yamls, kubeYaml)
+		Expect(err).To(BeNil())
+
+		kube := podmanTest.Podman([]string{"play", "kube", kubeYaml})
+		kube.WaitWithDefaultTimeout()
+		Expect(kube).Should(Exit(0))
+
+		cmData := podmanTest.Podman([]string{"exec", getCtrNameInPod(pod), "cat", "/test/BAR"})
+		cmData.WaitWithDefaultTimeout()
+		Expect(cmData).Should(Exit(0))
+		Expect(cmData.OutputToString()).To(Equal("foobar"))
+
+		cmData = podmanTest.Podman([]string{"exec", getCtrNameInPod(pod), "cat", "/test/FOO"})
+		cmData.WaitWithDefaultTimeout()
+		Expect(cmData).Should(Not(Exit(0)))
+	})
+
+	It("podman play kube with a missing optional ConfigMap volume", func() {
+		volumeName := "cmVol"
+
+		ctr := getCtr(withVolumeMount("/test", false), withImage(BB))
+		pod := getPod(withVolume(getConfigMapVolume(volumeName, []map[string]string{}, true)), withCtr(ctr))
+		err = generateKubeYaml("pod", pod, kubeYaml)
+		Expect(err).To(BeNil())
+
+		kube := podmanTest.Podman([]string{"play", "kube", kubeYaml})
+		kube.WaitWithDefaultTimeout()
+		Expect(kube).Should(Exit(0))
+	})
+
 	It("podman play kube applies labels to pods", func() {
 		var numReplicas int32 = 5
 		expectedLabelKey := "key1"