feature: add --working-mode flag for yurthub (#483)

cmd/yurthub/app/config/config.go

@@ -34,6 +34,7 @@ import (
 	"github.com/openyurtio/openyurt/pkg/yurthub/kubernetes/meta"
 	"github.com/openyurtio/openyurt/pkg/yurthub/kubernetes/serializer"
 	"github.com/openyurtio/openyurt/pkg/yurthub/storage/factory"
+	"github.com/openyurtio/openyurt/pkg/yurthub/util"
 	yurtclientset "github.com/openyurtio/yurt-app-manager-api/pkg/yurtappmanager/client/clientset/versioned"
 	yurtinformers "github.com/openyurtio/yurt-app-manager-api/pkg/yurtappmanager/client/informers/externalversions"
 
@@ -78,6 +79,7 @@ type YurtHubConfiguration struct {
 	Filters                           *filter.Filters
 	SharedFactory                     informers.SharedInformerFactory
 	YurtSharedFactory                 yurtinformers.SharedInformerFactory
+	WorkingMode                       util.WorkingMode
 }
 
 // Complete converts *options.YurtHubOptions to *YurtHubConfiguration
@@ -109,6 +111,9 @@ func Complete(options *options.YurtHubOptions) (*YurtHubConfiguration, error) {
 	var filters *filter.Filters
 	var mutatedMasterServiceAddr string
 	if options.EnableResourceFilter {
+		if options.WorkingMode == string(util.WorkingModeCloud) {
+			options.DisabledResourceFilters = append(options.DisabledResourceFilters, filter.DisabledInCloudMode...)
+		}
 		filters = filter.NewFilters(options.DisabledResourceFilters)
 		registerAllFilters(filters)
 
@@ -145,6 +150,7 @@ func Complete(options *options.YurtHubOptions) (*YurtHubConfiguration, error) {
 		EnableDummyIf:                     options.EnableDummyIf,
 		EnableIptables:                    options.EnableIptables,
 		HubAgentDummyIfName:               options.HubAgentDummyIfName,
+		WorkingMode:                       util.WorkingMode(options.WorkingMode),
 		StorageWrapper:                    storageWrapper,
 		SerializerManager:                 serializerManager,
 		RESTMapperManager:                 restMapperManager,

cmd/yurthub/app/options/options.go

@@ -62,6 +62,7 @@ type YurtHubOptions struct {
 	AccessServerThroughHub    bool
 	EnableResourceFilter      bool
 	DisabledResourceFilters   []string
+	WorkingMode               string
 }
 
 // NewYurtHubOptions creates a new YurtHubOptions with a default config.
@@ -90,6 +91,7 @@ func NewYurtHubOptions() *YurtHubOptions {
 		AccessServerThroughHub:    true,
 		EnableResourceFilter:      true,
 		DisabledResourceFilters:   make([]string, 0),
+		WorkingMode:               string(util.WorkingModeEdge),
 	}
 	return o
 }
@@ -112,6 +114,10 @@ func ValidateOptions(options *YurtHubOptions) error {
 		return fmt.Errorf("cert manage mode %s is not supported", options.CertMgrMode)
 	}
 
+	if !util.IsSupportedWorkingMode(util.WorkingMode(options.WorkingMode)) {
+		return fmt.Errorf("working mode %s is not supported", options.WorkingMode)
+	}
+
 	if err := verifyDummyIP(options.HubAgentDummyIfIP); err != nil {
 		return fmt.Errorf("dummy ip %s is not invalid, %v", options.HubAgentDummyIfIP, err)
 	}
@@ -139,7 +145,7 @@ func (o *YurtHubOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&o.JoinToken, "join-token", o.JoinToken, "the Join token for bootstrapping hub agent when --cert-mgr-mode=hubself.")
 	fs.StringVar(&o.RootDir, "root-dir", o.RootDir, "directory path for managing hub agent files(pki, cache etc).")
 	fs.BoolVar(&o.Version, "version", o.Version, "print the version information.")
-	fs.BoolVar(&o.EnableProfiling, "profiling", o.EnableProfiling, "Enable profiling via web interface host:port/debug/pprof/")
+	fs.BoolVar(&o.EnableProfiling, "profiling", o.EnableProfiling, "enable profiling via web interface host:port/debug/pprof/")
 	fs.BoolVar(&o.EnableDummyIf, "enable-dummy-if", o.EnableDummyIf, "enable dummy interface or not")
 	fs.BoolVar(&o.EnableIptables, "enable-iptables", o.EnableIptables, "enable iptables manager to setup rules for accessing hub agent")
 	fs.StringVar(&o.HubAgentDummyIfIP, "dummy-if-ip", o.HubAgentDummyIfIP, "the ip address of dummy interface that used for container connect hub agent(exclusive ips: 169.254.31.0/24, 169.254.1.1/32)")
@@ -149,6 +155,7 @@ func (o *YurtHubOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.BoolVar(&o.EnableResourceFilter, "enable-resource-filter", o.EnableResourceFilter, "enable to filter response that comes back from reverse proxy")
 	fs.StringSliceVar(&o.DisabledResourceFilters, "disabled-resource-filters", o.DisabledResourceFilters, "disable resource filters to handle response")
 	fs.StringVar(&o.NodePoolName, "nodepool-name", o.NodePoolName, "the name of node pool that runs hub agent")
+	fs.StringVar(&o.WorkingMode, "working-mode", o.WorkingMode, "the working mode of yurthub(edge, cloud).")
 }
 
 // verifyDummyIP verify the specified ip is valid or not

cmd/yurthub/app/start.go

@@ -36,6 +36,7 @@ import (
 	"github.com/openyurtio/openyurt/pkg/yurthub/proxy"
 	"github.com/openyurtio/openyurt/pkg/yurthub/server"
 	"github.com/openyurtio/openyurt/pkg/yurthub/transport"
+	"github.com/openyurtio/openyurt/pkg/yurthub/util"
 
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -125,19 +126,28 @@ func Run(cfg *config.YurtHubConfiguration, stopCh <-chan struct{}) error {
 	}
 	trace++
 
-	klog.Infof("%d. new cache manager with storage wrapper and serializer manager", trace)
-	cacheMgr, err := cachemanager.NewCacheManager(cfg.StorageWrapper, cfg.SerializerManager, cfg.RESTMapperManager, cfg.SharedFactory)
-	if err != nil {
-		return fmt.Errorf("could not new cache manager, %v", err)
+	var cacheMgr cachemanager.CacheManager
+	if cfg.WorkingMode == util.WorkingModeEdge {
+		klog.Infof("%d. new cache manager with storage wrapper and serializer manager", trace)
+		cacheMgr, err = cachemanager.NewCacheManager(cfg.StorageWrapper, cfg.SerializerManager, cfg.RESTMapperManager, cfg.SharedFactory)
+		if err != nil {
+			return fmt.Errorf("could not new cache manager, %v", err)
+		}
+	} else {
+		klog.Infof("%d. disable cache manager for node %s because it is a cloud node", trace, cfg.NodeName)
 	}
 	trace++
 
-	klog.Infof("%d. new gc manager for node %s, and gc frequency is a random time between %d min and %d min", trace, cfg.NodeName, cfg.GCFrequency, 3*cfg.GCFrequency)
-	gcMgr, err := gc.NewGCManager(cfg, restConfigMgr, stopCh)
-	if err != nil {
-		return fmt.Errorf("could not new gc manager, %v", err)
+	if cfg.WorkingMode == util.WorkingModeEdge {
+		klog.Infof("%d. new gc manager for node %s, and gc frequency is a random time between %d min and %d min", trace, cfg.NodeName, cfg.GCFrequency, 3*cfg.GCFrequency)
+		gcMgr, err := gc.NewGCManager(cfg, restConfigMgr, stopCh)
+		if err != nil {
+			return fmt.Errorf("could not new gc manager, %v", err)
+		}
+		gcMgr.Run()
+	} else {
+		klog.Infof("%d. disable gc manager for node %s because it is a cloud node", trace, cfg.NodeName)
 	}
-	gcMgr.Run()
 	trace++
 
 	klog.Infof("%d. new filter chain for mutating response body", trace)

pkg/yurthub/filter/constant.go

@@ -29,3 +29,6 @@ const (
 	// on kube-proxy list/watch service request from edge nodes.
 	DiscardCloudServiceFilterName = "discardcloudservice"
 )
+
+// DisabledInCloudMode contains the filters that should be disabled when yurthub is working in cloud mode.
+var DisabledInCloudMode = []string{DiscardCloudServiceFilterName}

pkg/yurthub/proxy/proxy.go

@@ -73,10 +73,17 @@ func NewYurtReverseProxyHandler(
 		return nil, err
 	}
 
+	var localProxy *local.LocalProxy
+	// When yurthub is working in cloud mode, cacheMgr will be set to nil which means the local cache is disabled,
+	// so we don't need to create a LocalProxy.
+	if cacheMgr != nil {
+		localProxy = local.NewLocalProxy(cacheMgr, lb.IsHealthy)
+	}
+
 	yurtProxy := &yurtReverseProxy{
 		resolver:            resolver,
 		loadBalancer:        lb,
-		localProxy:          local.NewLocalProxy(cacheMgr, lb.IsHealthy),
+		localProxy:          localProxy,
 		cacheMgr:            cacheMgr,
 		maxRequestsInFlight: yurtHubCfg.MaxRequestInFlight,
 		stopCh:              stopCh,
@@ -88,17 +95,21 @@ func NewYurtReverseProxyHandler(
 func (p *yurtReverseProxy) buildHandlerChain(handler http.Handler) http.Handler {
 	handler = util.WithRequestTrace(handler)
 	handler = util.WithRequestContentType(handler)
-	handler = util.WithCacheHeaderCheck(handler)
+	if p.cacheMgr != nil {
+		handler = util.WithCacheHeaderCheck(handler)
+	}
 	handler = util.WithRequestTimeout(handler)
-	handler = util.WithListRequestSelector(handler)
+	if p.cacheMgr != nil {
+		handler = util.WithListRequestSelector(handler)
+	}
 	handler = util.WithMaxInFlightLimit(handler, p.maxRequestsInFlight)
 	handler = util.WithRequestClientComponent(handler)
 	handler = filters.WithRequestInfo(handler, p.resolver)
 	return handler
 }
 
 func (p *yurtReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
-	if !hubutil.IsKubeletLeaseReq(req) && p.loadBalancer.IsHealthy() {
+	if !hubutil.IsKubeletLeaseReq(req) && p.loadBalancer.IsHealthy() || p.localProxy == nil {
 		p.loadBalancer.ServeHTTP(rw, req)
 	} else {
 		p.localProxy.ServeHTTP(rw, req)

pkg/yurthub/proxy/remote/remote.go

@@ -130,30 +130,32 @@ func (rp *RemoteProxy) modifyResponse(resp *http.Response) error {
 		}
 	}
 
-	// cache resp with storage interface
 	if resp.StatusCode >= http.StatusOK && resp.StatusCode <= http.StatusPartialContent {
-		if rp.cacheMgr.CanCacheFor(req) {
-			reqContentType, _ := util.ReqContentTypeFrom(ctx)
-			respContentType := resp.Header.Get("Content-Type")
-			if len(respContentType) == 0 {
-				respContentType = reqContentType
+		// prepare response content type
+		reqContentType, _ := util.ReqContentTypeFrom(ctx)
+		respContentType := resp.Header.Get("Content-Type")
+		if len(respContentType) == 0 {
+			respContentType = reqContentType
+		}
+		ctx = util.WithRespContentType(ctx, respContentType)
+		req = req.WithContext(ctx)
+
+		// filter response data
+		if rp.filterChain != nil {
+			size, filterRc, err := rp.filterChain.Filter(req, resp.Body, rp.stopCh)
+			if err != nil {
+				klog.Errorf("failed to filter response for %s, %v", util.ReqString(req), err)
+				return err
 			}
-			ctx = util.WithRespContentType(ctx, respContentType)
-			req = req.WithContext(ctx)
-
-			if rp.filterChain != nil {
-				size, filterRc, err := rp.filterChain.Filter(req, resp.Body, rp.stopCh)
-				if err != nil {
-					klog.Errorf("failed to filter response for %s, %v", util.ReqString(req), err)
-					return err
-				}
-				resp.Body = filterRc
-				if size > 0 {
-					resp.ContentLength = int64(size)
-					resp.Header.Set("Content-Length", fmt.Sprint(size))
-				}
+			resp.Body = filterRc
+			if size > 0 {
+				resp.ContentLength = int64(size)
+				resp.Header.Set("Content-Length", fmt.Sprint(size))
 			}
+		}
 
+		// cache resp with storage interface
+		if rp.cacheMgr != nil && rp.cacheMgr.CanCacheFor(req) {
 			rc, prc := util.NewDualReadCloser(req, resp.Body, true)
 			go func(req *http.Request, prc io.ReadCloser, stopCh <-chan struct{}) {
 				err := rp.cacheMgr.CacheResponse(req, prc, stopCh)
@@ -164,7 +166,7 @@ func (rp *RemoteProxy) modifyResponse(resp *http.Response) error {
 
 			resp.Body = rc
 		}
-	} else if resp.StatusCode == http.StatusNotFound && info.Verb == "list" {
+	} else if resp.StatusCode == http.StatusNotFound && info.Verb == "list" && rp.cacheMgr != nil {
 		// 404 Not Found: The CRD may have been unregistered and should be updated locally as well.
 		// Other types of requests may return a 404 response for other reasons (for example, getting a pod that doesn't exist).
 		// And the main purpose is to return 404 when list an unregistered resource locally, so here only consider the list request.
@@ -184,7 +186,7 @@ func (rp *RemoteProxy) modifyResponse(resp *http.Response) error {
 
 func (rp *RemoteProxy) errorHandler(rw http.ResponseWriter, req *http.Request, err error) {
 	klog.V(2).Infof("remote proxy error handler: %s, %v", util.ReqString(req), err)
-	if !rp.cacheMgr.CanCacheFor(req) {
+	if rp.cacheMgr == nil || !rp.cacheMgr.CanCacheFor(req) {
 		rw.WriteHeader(http.StatusBadGateway)
 		return
 	}

pkg/yurthub/util/util.go

@@ -45,6 +45,16 @@ import (
 // ProxyKeyType represents the key in proxy request context
 type ProxyKeyType int
 
+// WorkingMode represents the working mode of yurthub.
+type WorkingMode string
+
+const (
+	// WorkingModeCloud represents yurthub is working in cloud mode, which means yurthub is deployed on the cloud side.
+	WorkingModeCloud WorkingMode = "cloud"
+	// WorkingModeEdge represents yurthub is working in edge mode, which means yurthub is deployed on the edge side.
+	WorkingModeEdge WorkingMode = "edge"
+)
+
 const (
 	// YurtHubCertificateManagerName represents the certificateManager name in yurthub mode
 	YurtHubCertificateManagerName = "hubself"
@@ -321,6 +331,16 @@ func IsSupportedCertMode(certMode string) bool {
 	return false
 }
 
+// IsSupportedWorkingMode check working mode is supported or not
+func IsSupportedWorkingMode(workingMode WorkingMode) bool {
+	switch workingMode {
+	case WorkingModeCloud, WorkingModeEdge:
+		return true
+	}
+
+	return false
+}
+
 // FileExists checks if specified file exists.
 func FileExists(filename string) (bool, error) {
 	if _, err := os.Stat(filename); os.IsNotExist(err) {