Added subpath functionality to --mount flag

CHANGELOG.adoc

@@ -32,6 +32,10 @@
 | Added --scale-metric flag to configure metric name
 | https://github.com/knative/client/pull/1653[#1653]
 
+| 🎁
+| Added subpath functionality to --mount flag
+| https://github.com/knative/client/pull/1655[#1655]
+
 |===
 ## v1.3.0 (2022-03-08)
 [cols="1,10,3", options="header", width="100%"]

docs/cmd/kn_container_add.md

@@ -38,7 +38,7 @@ kn container add NAME
   -h, --help                         help for add
       --image string                 Image to run.
       --limit strings                The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
-      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -p, --port string                  The port where application listens on, in the format 'NAME:PORT', where 'NAME' is optional. Examples: '--port h2c:8080' , '--port 8080'.
       --pull-policy string           Image pull policy. Valid values (case insensitive): Always | Never | IfNotPresent
       --pull-secret string           Image pull secret to set. An empty argument ("") clears the pull secret. The referenced secret must exist in the service's namespace.

docs/cmd/kn_service_apply.md

@@ -50,7 +50,7 @@ kn service apply s0 --filename my-svc.yml
       --label-service stringArray         Service label to set. name=value; you may provide this flag any number of times to set multiple labels. To unset, specify the label name followed by a "-" (e.g., name-). This flag takes precedence over the "label" flag.
       --limit strings                     The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
       --lock-to-digest                    Keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision) (default true)
-      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -n, --namespace string                  Specify the namespace to operate in.
       --no-cluster-local                  Do not specify that the service be private. (--no-cluster-local will make the service publicly available) (default true)
       --no-lock-to-digest                 Do not keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision)

docs/cmd/kn_service_create.md

@@ -75,7 +75,7 @@ kn service create NAME --image IMAGE
       --label-service stringArray         Service label to set. name=value; you may provide this flag any number of times to set multiple labels. To unset, specify the label name followed by a "-" (e.g., name-). This flag takes precedence over the "label" flag.
       --limit strings                     The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
       --lock-to-digest                    Keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision) (default true)
-      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -n, --namespace string                  Specify the namespace to operate in.
       --no-cluster-local                  Do not specify that the service be private. (--no-cluster-local will make the service publicly available) (default true)
       --no-lock-to-digest                 Do not keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision)

docs/cmd/kn_service_update.md

@@ -62,7 +62,7 @@ kn service update NAME
       --label-service stringArray         Service label to set. name=value; you may provide this flag any number of times to set multiple labels. To unset, specify the label name followed by a "-" (e.g., name-). This flag takes precedence over the "label" flag.
       --limit strings                     The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
       --lock-to-digest                    Keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision) (default true)
-      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray                 Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -n, --namespace string                  Specify the namespace to operate in.
       --no-cluster-local                  Do not specify that the service be private. (--no-cluster-local will make the service publicly available) (default true)
       --no-lock-to-digest                 Do not keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision)

docs/cmd/kn_source_container_create.md

@@ -27,7 +27,7 @@ kn source container create NAME --image IMAGE --sink SINK
   -h, --help                         help for create
       --image string                 Image to run.
       --limit strings                The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
-      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -n, --namespace string             Specify the namespace to operate in.
   -p, --port string                  The port where application listens on, in the format 'NAME:PORT', where 'NAME' is optional. Examples: '--port h2c:8080' , '--port 8080'.
       --pull-policy string           Image pull policy. Valid values (case insensitive): Always | Never | IfNotPresent

docs/cmd/kn_source_container_update.md

@@ -27,7 +27,7 @@ kn source container update NAME --image IMAGE
   -h, --help                         help for update
       --image string                 Image to run.
       --limit strings                The resource requirement limits for this Service. For example, 'cpu=100m,memory=256Mi'. You can use this flag multiple times. To unset a resource limit, append "-" to the resource name, e.g. '--limit memory-'.
-      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
+      --mount stringArray            Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can specify a volume subpath by following the volume name with slash separated path. Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
   -n, --namespace string             Specify the namespace to operate in.
   -p, --port string                  The port where application listens on, in the format 'NAME:PORT', where 'NAME' is optional. Examples: '--port h2c:8080' , '--port 8080'.
       --pull-policy string           Image pull policy. Valid values (case insensitive): Always | Never | IfNotPresent

pkg/kn/flags/podspec.go

@@ -140,6 +140,8 @@ func (p *PodSpecFlags) AddFlags(flagset *pflag.FlagSet) []string {
 		"Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. "+
 			"Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. "+
 			"When a configmap or a secret is specified, a corresponding volume is automatically generated. "+
+			"You can specify a volume subpath by following the volume name with slash separated path. "+
+			"Example: --mount /mydir=cm:myconfigmap/subpath/to/be/mounted. "+
 			"You can use this flag multiple times. "+
 			"For unmounting a directory, append \"-\", e.g. --mount /mydir-, which also removes any auto-generated volume.")
 	flagNames = append(flagNames, "mount")

pkg/kn/flags/podspec_helper.go

@@ -38,6 +38,11 @@ const (
 	PortFormatErr = "the port specification '%s' is not valid. Please provide in the format 'NAME:PORT', where 'NAME' is optional. Examples: '--port h2c:8080' , '--port 8080'."
 )
 
+type MountInfo struct {
+	VolumeName string
+	SubPath    string
+}
+
 func (vt VolumeSourceType) String() string {
 	names := [...]string{"config-map", "secret"}
 	if vt < ConfigMapVolumeSourceType || vt > SecretVolumeSourceType {
@@ -473,26 +478,32 @@ func updateVolumeMountsFromMap(volumeMounts []corev1.VolumeMount, toUpdate *util
 
 	for i := range volumeMounts {
 		volumeMount := &volumeMounts[i]
-		name, present := toUpdate.GetString(volumeMount.MountPath)
+		mountInfo, present := toUpdate.Get(volumeMount.MountPath)
 
 		if present {
+			volumeMountInfo := mountInfo.(*MountInfo)
+			name := volumeMountInfo.VolumeName
 			if !existsVolumeNameInVolumes(name, volumes) {
 				return nil, fmt.Errorf("There is no volume matched with %q", name)
 			}
 
 			volumeMount.ReadOnly = true
 			volumeMount.Name = name
+			volumeMount.SubPath = volumeMountInfo.SubPath
 			set[volumeMount.MountPath] = true
 		}
 	}
 
 	it := toUpdate.Iterator()
-	for mountPath, name, ok := it.NextString(); ok; mountPath, name, ok = it.NextString() {
+	for mountPath, mountInfo, ok := it.Next(); ok; mountPath, mountInfo, ok = it.Next() {
+		volumeMountInfo := mountInfo.(*MountInfo)
+		name := volumeMountInfo.VolumeName
 		if !set[mountPath] {
 			volumeMounts = append(volumeMounts, corev1.VolumeMount{
 				Name:      name,
 				ReadOnly:  true,
 				MountPath: mountPath,
+				SubPath:   volumeMountInfo.SubPath,
 			})
 		}
 	}
@@ -658,6 +669,19 @@ func existsVolumeNameInVolumeMounts(volumeName string, volumeMounts []corev1.Vol
 
 // =======================================================================================
 
+func getMountInfo(volume string) *MountInfo {
+	slices := strings.SplitN(volume, "/", 2)
+	if len(slices) == 1 || slices[1] == "" {
+		return &MountInfo{
+			VolumeName: slices[0],
+		}
+	}
+	return &MountInfo{
+		VolumeName: slices[0],
+		SubPath:    slices[1],
+	}
+}
+
 func reviseVolumeInfoAndMountsToUpdate(mountsToUpdate *util.OrderedMap, volumesToUpdate *util.OrderedMap) (*util.OrderedMap, *util.OrderedMap, error) {
 	volumeSourceInfoByName := util.NewOrderedMap() //make(map[string]*volumeSourceInfo)
 	mountsToUpdateRevised := util.NewOrderedMap()  //make(map[string]string)
@@ -668,23 +692,28 @@ func reviseVolumeInfoAndMountsToUpdate(mountsToUpdate *util.OrderedMap, volumesT
 		// slices[1] -> secret, config-map, or volume name
 		slices := strings.SplitN(value, ":", 2)
 		if len(slices) == 1 {
-			mountsToUpdateRevised.Set(path, slices[0])
+			mountInfo := getMountInfo(slices[0])
+			mountsToUpdateRevised.Set(path, mountInfo)
 		} else {
 			switch volumeType := slices[0]; volumeType {
 			case "config-map", "cm":
 				generatedName := util.GenerateVolumeName(path)
+				mountInfo := getMountInfo(slices[1])
 				volumeSourceInfoByName.Set(generatedName, &volumeSourceInfo{
 					volumeSourceType: ConfigMapVolumeSourceType,
-					volumeSourceName: slices[1],
+					volumeSourceName: mountInfo.VolumeName,
 				})
-				mountsToUpdateRevised.Set(path, generatedName)
+				mountInfo.VolumeName = generatedName
+				mountsToUpdateRevised.Set(path, mountInfo)
 			case "secret", "sc":
 				generatedName := util.GenerateVolumeName(path)
+				mountInfo := getMountInfo(slices[1])
 				volumeSourceInfoByName.Set(generatedName, &volumeSourceInfo{
 					volumeSourceType: SecretVolumeSourceType,
-					volumeSourceName: slices[1],
+					volumeSourceName: mountInfo.VolumeName,
 				})
-				mountsToUpdateRevised.Set(path, generatedName)
+				mountInfo.VolumeName = generatedName
+				mountsToUpdateRevised.Set(path, mountInfo)
 
 			default:
 				return nil, nil, fmt.Errorf("unsupported volume type \"%q\"; supported volume types are \"config-map or cm\", \"secret or sc\", and \"volume or vo\"", slices[0])

pkg/kn/flags/podspec_test.go

@@ -136,6 +136,54 @@ func TestPodSpecResolve(t *testing.T) {
 	testCmd.Execute()
 }
 
+func TestPodSpecMountResolveSubPath(t *testing.T) {
+	args := map[string]*MountInfo{
+		"/mydir=cm:my-cm": {
+			VolumeName: "my-cm",
+		},
+		"/mydir=sc:my-sec": {
+			VolumeName: "my-sec",
+		},
+		"/mydir=myvol": {
+			VolumeName: "myvol",
+		},
+
+		"/mydir=cm:my-cm/subpath/to/mount": {
+			VolumeName: "my-cm",
+			SubPath:    "subpath/to/mount",
+		},
+		"/mydir=sc:my-sec/subpath/to/mount": {
+			VolumeName: "my-sec",
+			SubPath:    "subpath/to/mount",
+		},
+		"/mydir=myvol/subpath/to/mount": {
+			VolumeName: "myvol",
+			SubPath:    "subpath/to/mount",
+		},
+	}
+
+	for arg, mountInfo := range args {
+		outBuf := bytes.Buffer{}
+		flags := &PodSpecFlags{}
+		inputArgs := append([]string{"--image", "repo/user/imageID:tag", "--mount"}, arg)
+		testCmd := &cobra.Command{
+			Use: "test",
+			Run: func(cmd *cobra.Command, args []string) {
+				podSpec := &corev1.PodSpec{Containers: []corev1.Container{{}}}
+				err := flags.ResolvePodSpec(podSpec, cmd.Flags(), inputArgs)
+				assert.NilError(t, err)
+				assert.Equal(t, podSpec.Containers[0].VolumeMounts[0].SubPath, mountInfo.SubPath)
+			},
+		}
+		testCmd.SetOut(&outBuf)
+
+		testCmd.SetArgs(inputArgs)
+		flags.AddFlags(testCmd.Flags())
+		flags.AddCreateFlags(testCmd.Flags())
+		testCmd.Execute()
+	}
+}
+
 func TestPodSpecResolveContainers(t *testing.T) {
 	rawInput := `
 containers: