Merge pull request #51914 from sergeylanzman/master

Automatic merge from submit-queue (batch tested with PRs 55392, 55491, 51914, 55831, 55836). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Move regexp.MustCompile to global variable

Move regexp.MustCompile to global variable.
regexp.MustCompile heavy function and can be run on init app
```release-note
NONE
```

pkg/kubectl/cmd/set/set_env.go

@@ -39,7 +39,8 @@ import (
 )
 
 var (
-	envResources = `
+	validEnvNameRegexp = regexp.MustCompile("[^a-zA-Z0-9_]")
+	envResources       = `
   	pod (po), replicationcontroller (rc), deployment (deploy), daemonset (ds), job, replicaset (rs)`
 
 	envLong = templates.LongDesc(`
@@ -172,7 +173,6 @@ func validateNoOverwrites(existing []v1.EnvVar, env []v1.EnvVar) error {
 }
 
 func keyToEnvName(key string) string {
-	validEnvNameRegexp := regexp.MustCompile("[^a-zA-Z0-9_]")
 	return strings.ToUpper(validEnvNameRegexp.ReplaceAllString(key, "_"))
 }
 

pkg/kubelet/gpu/nvidia/nvidia_gpu_manager.go

@@ -44,8 +44,11 @@ const (
 	// Optional device.
 	nvidiaUVMToolsDevice string = "/dev/nvidia-uvm-tools"
 	devDirectory                = "/dev"
-	nvidiaDeviceRE              = `^nvidia[0-9]*$`
-	nvidiaFullpathRE            = `^/dev/nvidia[0-9]*$`
+)
+
+var (
+	nvidiaDeviceRE   = regexp.MustCompile(`^nvidia[0-9]*$`)
+	nvidiaFullpathRE = regexp.MustCompile(`^/dev/nvidia[0-9]*$`)
 )
 
 type activePodsLister interface {
@@ -194,7 +197,6 @@ func (ngm *nvidiaGPUManager) updateAllocatedGPUs() {
 // we want more features, features like schedule containers according to GPU family
 // name.
 func (ngm *nvidiaGPUManager) discoverGPUs() error {
-	reg := regexp.MustCompile(nvidiaDeviceRE)
 	files, err := ioutil.ReadDir(devDirectory)
 	if err != nil {
 		return err
@@ -203,7 +205,7 @@ func (ngm *nvidiaGPUManager) discoverGPUs() error {
 		if f.IsDir() {
 			continue
 		}
-		if reg.MatchString(f.Name()) {
+		if nvidiaDeviceRE.MatchString(f.Name()) {
 			glog.V(2).Infof("Found Nvidia GPU %q", f.Name())
 			ngm.allGPUs.Insert(path.Join(devDirectory, f.Name()))
 		}
@@ -274,5 +276,5 @@ func (ngm *nvidiaGPUManager) gpusInUse() *podGPUs {
 }
 
 func isValidPath(path string) bool {
-	return regexp.MustCompile(nvidiaFullpathRE).MatchString(path)
+	return nvidiaFullpathRE.MatchString(path)
 }

pkg/volume/iscsi/iscsi_util.go

@@ -43,6 +43,8 @@ var (
 		"node.session.auth.password",
 		"node.session.auth.username_in",
 		"node.session.auth.password_in"}
+	ifaceTransportNameRe = regexp.MustCompile(`iface.transport_name = (.*)\n`)
+	ifaceRe              = regexp.MustCompile(`.+/iface-([^/]+)/.+`)
 )
 
 func updateISCSIDiscoverydb(b iscsiDiskMounter, tp string) error {
@@ -429,9 +431,7 @@ func (util *ISCSIUtil) DetachDisk(c iscsiDiskUnmounter, mntPath string) error {
 }
 
 func extractTransportname(ifaceOutput string) (iscsiTransport string) {
-	re := regexp.MustCompile(`iface.transport_name = (.*)\n`)
-
-	rexOutput := re.FindStringSubmatch(ifaceOutput)
+	rexOutput := ifaceTransportNameRe.FindStringSubmatch(ifaceOutput)
 	if rexOutput == nil {
 		return ""
 	}
@@ -460,9 +460,7 @@ func extractDeviceAndPrefix(mntPath string) (string, string, error) {
 }
 
 func extractIface(mntPath string) (string, bool) {
-	re := regexp.MustCompile(`.+/iface-([^/]+)/.+`)
-
-	reOutput := re.FindStringSubmatch(mntPath)
+	reOutput := ifaceRe.FindStringSubmatch(mntPath)
 	if reOutput != nil {
 		return reOutput[1], true
 	}

pkg/volume/rbd/rbd_util.go

@@ -46,6 +46,10 @@ const (
 	rbdCmdErr       = "executable file not found in $PATH"
 )
 
+var (
+	clientKubeLockMagicRe = regexp.MustCompile("client.* " + kubeLockMagic + ".*")
+)
+
 // search /sys/bus for rbd device that matches given pool and image
 func getDevFromImageAndPool(pool, image string) (string, bool) {
 	// /sys/bus/rbd/devices/X/name and /sys/bus/rbd/devices/X/pool
@@ -183,8 +187,7 @@ func (util *RBDUtil) rbdLock(b rbdMounter, lock bool) error {
 			}
 
 			// best effort clean up orphaned locked if not used
-			re := regexp.MustCompile("client.* " + kubeLockMagic + ".*")
-			locks := re.FindAllStringSubmatch(output, -1)
+			locks := clientKubeLockMagicRe.FindAllStringSubmatch(output, -1)
 			for _, v := range locks {
 				if len(v) > 0 {
 					lockInfo := strings.Split(v[0], " ")

staging/src/k8s.io/client-go/util/jsonpath/parser.go

@@ -43,7 +43,11 @@ type Parser struct {
 	width int
 }
 
-var ErrSyntax = errors.New("invalid syntax")
+var (
+	ErrSyntax        = errors.New("invalid syntax")
+	dictKeyRex       = regexp.MustCompile(`^'([^']*)'$`)
+	sliceOperatorRex = regexp.MustCompile(`^(-?[\d]*)(:-?[\d]*)?(:[\d]*)?$`)
+)
 
 // Parse parsed the given text and return a node Parser.
 // If an error is encountered, parsing stops and an empty
@@ -283,8 +287,7 @@ Loop:
 	}
 
 	// dict key
-	reg := regexp.MustCompile(`^'([^']*)'$`)
-	value := reg.FindStringSubmatch(text)
+	value := dictKeyRex.FindStringSubmatch(text)
 	if value != nil {
 		parser, err := parseAction("arraydict", fmt.Sprintf(".%s", value[1]))
 		if err != nil {
@@ -297,8 +300,7 @@ Loop:
 	}
 
 	//slice operator
-	reg = regexp.MustCompile(`^(-?[\d]*)(:-?[\d]*)?(:[\d]*)?$`)
-	value = reg.FindStringSubmatch(text)
+	value = sliceOperatorRex.FindStringSubmatch(text)
 	if value == nil {
 		return fmt.Errorf("invalid array index %s", text)
 	}