support unique hostpath for fuse sidecar mode in webhook

Signed-off-by: 玖宇 <guotongyu.gty@alibaba-inc.com>

Author: 玖宇

pkg/application/inject/fuse/mutator/mutating_context.go

@@ -92,6 +92,7 @@ type mutatingContext struct {
 	appendedVolumeNames         map[string]string
 	datasetUsedInContainers     *bool
 	datasetUsedInInitContainers *bool
+	generateUniqueHostMountPath string
 }
 
 func (ctx *mutatingContext) GetAppendedVolumeNames() (nameMapping map[string]string, err error) {

pkg/application/inject/fuse/mutator/mutator_default.go

@@ -18,8 +18,12 @@ package mutator
 
 import (
 	"context"
+	"crypto/rand"
+	"encoding/hex"
 	"fmt"
+	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/go-logr/logr"
 	"github.com/pkg/errors"
@@ -180,10 +184,16 @@ func (helper *defaultMutatorHelper) Mutate() (*MutatingPodSpecs, error) {
 	return helper.Specs, nil
 }
 
-func (helper *defaultMutatorHelper) mutateDatasetVolumes() error {
+func (helper *defaultMutatorHelper) mutateDatasetVolumes() (err error) {
 	volumes := helper.Specs.Volumes
-
 	mountPath := helper.template.FuseMountInfo.HostMountPath
+	if common.HostPathMode(helper.Specs.MetaObj.Annotations[common.HostMountPathModeOnDefaultPlatformKey]) == common.HostPathModeRandomSuffix {
+		mountPath, err = helper.generateUniqueHostPath(mountPath)
+		if err != nil {
+			return err
+		}
+	}
+
 	if helper.template.FuseMountInfo.SubPath != "" {
 		mountPath = mountPath + "/" + helper.template.FuseMountInfo.SubPath
 	}
@@ -243,6 +253,17 @@ func (helper *defaultMutatorHelper) appendFuseContainerVolumes() (err error) {
 		volumeNames = append(volumeNames, volume.Name)
 	}
 
+	if common.HostPathMode(helper.Specs.MetaObj.Annotations[common.HostMountPathModeOnDefaultPlatformKey]) == common.HostPathModeRandomSuffix {
+		for index, volume := range volumesToAdd {
+			if utils.IsVolumeNameHasPrefixes(volume, hostMountNames) {
+				if volume.HostPath != nil {
+					volume.HostPath.Path = fmt.Sprintf("%s/%s", volume.HostPath.Path, helper.ctx.generateUniqueHostMountPath)
+					volumesToAdd[index] = volume
+				}
+			}
+		}
+	}
+
 	// Append volumes
 	ctxAppenedVolumeNames, err := helper.ctx.GetAppendedVolumeNames()
 	if err != nil {
@@ -393,6 +414,29 @@ func (helper *defaultMutatorHelper) enablePrometheusMetricsScrape() {
 		helper.Specs.MetaObj.Annotations[common.AnnotationPrometheusFuseMetricsScrapeKey] = "true"
 	}
 }
+func (helper *defaultMutatorHelper) generateUniqueHostPath(originalMountPath string) (string, error) {
+	bytes := make([]byte, 8)
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+	uniqueDirName := hex.EncodeToString(bytes)[:8]
+
+	name := helper.Specs.MetaObj.Name
+	if helper.Specs.MetaObj.Name == "" {
+		name = helper.Specs.MetaObj.GenerateName + "--generate-name"
+	}
+	generateUniqueHostMountPath := fmt.Sprintf("%s/%d-%s", name, time.Now().UnixMicro(), uniqueDirName)
+	helper.ctx.generateUniqueHostMountPath = generateUniqueHostMountPath
+
+	mountPathParts := strings.Split(originalMountPath, string(filepath.Separator))
+	if len(mountPathParts) < 2 {
+		return "", fmt.Errorf("unsupported host mount path format: %s", originalMountPath)
+	}
+	baseComponents := mountPathParts[:len(mountPathParts)-1]
+	lastComponent := mountPathParts[len(mountPathParts)-1]
+	newPathComponents := append(baseComponents, generateUniqueHostMountPath, lastComponent)
+	return fmt.Sprintf("/%s", filepath.Join(newPathComponents...)), nil
+}
 
 func (helper *defaultMutatorHelper) removeFuseMetricsContainerPort() {
 	if len(helper.template.FuseContainer.Ports) == 0 {

pkg/common/constants.go

@@ -143,6 +143,13 @@ const (
 	VolumeTypeVolumeTemplate VolumeType = "volumeTemplate"
 )
 
+type HostPathMode string
+
+const (
+	HostPathModeFixed        HostPathMode = "fixed"
+	HostPathModeRandomSuffix HostPathMode = "random-suffix"
+)
+
 // GetDefaultTieredStoreOrder get the TieredStoreOrder from the default Map
 // because the crd has validated the value, It's not possible to meet unknown MediumType
 func GetDefaultTieredStoreOrder(MediumType MediumType) (order int) {
@@ -215,5 +222,6 @@ const (
 )
 
 const (
-	SkipPrecheckAnnotationKey = "sidecar.fluid.io/skip-precheck"
+	SkipPrecheckAnnotationKey             = "sidecar.fluid.io/skip-precheck"
+	HostMountPathModeOnDefaultPlatformKey = "default.fuse-sidecar.fluid.io/host-mount-path-mode"
 )

pkg/utils/volumes.go

@@ -59,6 +59,16 @@ outer:
 	return
 }
 
+func IsVolumeNameHasPrefixes(input corev1.Volume, prefixes []string) bool {
+	for _, prefix := range prefixes {
+		if strings.HasPrefix(input.Name, prefix) {
+			return true
+		}
+	}
+
+	return false
+}
+
 func FindVolumeByVolumeMount(volumeMount corev1.VolumeMount, volumes []corev1.Volume) *corev1.Volume {
 	for _, vol := range volumes {
 		if vol.Name == volumeMount.Name {