From 80f8bf511ceeef0dac6293058c0f80023e15710a Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Mon, 23 Mar 2020 09:28:13 +0100 Subject: [PATCH 1/8] aggregator:introduces retry mechanism --- .../k8s.io/apimachinery/pkg/util/net/util.go | 19 +- .../pkg/util/proxy/upgradeaware.go | 5 +- .../pkg/apiserver/handler_proxy.go | 35 +++- .../pkg/apiserver/retry_detector.go | 157 +++++++++++++++ .../pkg/apiserver/retry_detector_test.go | 187 ++++++++++++++++++ 5 files changed, 394 insertions(+), 9 deletions(-) create mode 100644 staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go create mode 100644 staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go diff --git a/staging/src/k8s.io/apimachinery/pkg/util/net/util.go b/staging/src/k8s.io/apimachinery/pkg/util/net/util.go index 2e7cb9499465e..5b62978456ab9 100644 --- a/staging/src/k8s.io/apimachinery/pkg/util/net/util.go +++ b/staging/src/k8s.io/apimachinery/pkg/util/net/util.go @@ -17,6 +17,7 @@ limitations under the License. package net import ( + "errors" "net" "net/url" "os" @@ -40,13 +41,16 @@ func IPNetEqual(ipnet1, ipnet2 *net.IPNet) bool { // Returns if the given err is "connection reset by peer" error. func IsConnectionReset(err error) bool { - if urlErr, ok := err.(*url.Error); ok { + var urlErr *url.Error + if errors.As(err, &urlErr) { err = urlErr.Err } - if opErr, ok := err.(*net.OpError); ok { + var opErr *net.OpError + if errors.As(err, &opErr) { err = opErr.Err } - if osErr, ok := err.(*os.SyscallError); ok { + var osErr *os.SyscallError + if errors.As(err, &osErr) { err = osErr.Err } if errno, ok := err.(syscall.Errno); ok && errno == syscall.ECONNRESET { @@ -57,13 +61,16 @@ func IsConnectionReset(err error) bool { // Returns if the given err is "connection refused" error func IsConnectionRefused(err error) bool { - if urlErr, ok := err.(*url.Error); ok { + var urlErr *url.Error + if errors.As(err, &urlErr) { err = urlErr.Err } - if opErr, ok := err.(*net.OpError); ok { + var opErr *net.OpError + if errors.As(err, &opErr) { err = opErr.Err } - if osErr, ok := err.(*os.SyscallError); ok { + var osErr *os.SyscallError + if errors.As(err, &osErr) { err = osErr.Err } if errno, ok := err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED { diff --git a/staging/src/k8s.io/apimachinery/pkg/util/proxy/upgradeaware.go b/staging/src/k8s.io/apimachinery/pkg/util/proxy/upgradeaware.go index d007c10b50621..02e02e4b4ddc7 100644 --- a/staging/src/k8s.io/apimachinery/pkg/util/proxy/upgradeaware.go +++ b/staging/src/k8s.io/apimachinery/pkg/util/proxy/upgradeaware.go @@ -232,6 +232,7 @@ func (h *UpgradeAwareHandler) ServeHTTP(w http.ResponseWriter, req *http.Request proxy.Transport = h.Transport proxy.FlushInterval = h.FlushInterval proxy.ErrorLog = log.New(noSuppressPanicError{}, "", log.LstdFlags) + proxy.ErrorHandler = h.Responder.Error proxy.ServeHTTP(w, newReq) } @@ -412,12 +413,12 @@ func getResponse(r io.Reader) (*http.Response, []byte, error) { func dial(req *http.Request, transport http.RoundTripper) (net.Conn, error) { conn, err := dialURL(req.Context(), req.URL, transport) if err != nil { - return nil, fmt.Errorf("error dialing backend: %v", err) + return nil, fmt.Errorf("error dialing backend: %w", err) } if err = req.Write(conn); err != nil { conn.Close() - return nil, fmt.Errorf("error sending request: %v", err) + return nil, fmt.Errorf("error sending request: %w", err) } return conn, err diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go index 4d1f9a6dd1bd8..1cefab780989e 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go @@ -107,6 +107,37 @@ func proxyError(w http.ResponseWriter, req *http.Request, error string, code int } func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { + w = newStatusResponseWriter(w, req) + errRsp := newHijackResponder(&responder{w: w}, req) + // TODO: to builder pattern + retryManager := newHijackProtector(w.(*statusResponseWriter), newMaxRetries(newRetryDetector(errRsp), 3)) + + for { + // TODO: do we have to clone the req ? + // TODO: detect disconnected client + // TODO: pick up a different EP on retry + // TODO: always report the status to the service resolver - this will influence available EPs pool + // TODO: what to report ? + // - success, failure + // - response time + r.serveHTTP(w, req, errRsp) + + // TODO: add logs + // TODO: backoff, jitter + if !retryManager.ShouldRetry(){ + break + } + retryManager.Reset() + } + + if w.(*statusResponseWriter).statusCode == 0 && !w.(*statusResponseWriter).wasHijacked{ + // TODO: send HTTP 503 if the error is retriable + // otherwise send HTTP 500 + proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) + } +} + +func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errResponder proxy.ErrorResponder) { value := r.handlingInfo.Load() if value == nil { r.localDelegate.ServeHTTP(w, req) @@ -123,6 +154,7 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { } if !handlingInfo.serviceAvailable { + // TODO: retry proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) return } @@ -144,6 +176,7 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { rloc, err := r.serviceResolver.ResolveEndpoint(handlingInfo.serviceNamespace, handlingInfo.serviceName, handlingInfo.servicePort) if err != nil { klog.Errorf("error resolving %s/%s: %v", handlingInfo.serviceNamespace, handlingInfo.serviceName, err) + // TODO: retry proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) return } @@ -175,7 +208,7 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { transport.SetAuthProxyHeaders(newReq, user.GetName(), user.GetGroups(), user.GetExtra()) } - handler := proxy.NewUpgradeAwareHandler(location, proxyRoundTripper, true, upgrade, &responder{w: w}) + handler := proxy.NewUpgradeAwareHandler(location, proxyRoundTripper, true, upgrade, errResponder) handler.ServeHTTP(w, newReq) } diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go new file mode 100644 index 0000000000000..ed16baa8c7899 --- /dev/null +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go @@ -0,0 +1,157 @@ +package apiserver + +import ( + "bufio" + "fmt" + "net" + "net/http" + + knet "k8s.io/apimachinery/pkg/util/net" + "k8s.io/apimachinery/pkg/util/proxy" +) + +type retriable interface { + ShouldRetry() bool + Reset() +} + +type retryDetector struct { + delegates []retriable +} + +var _ retriable = &retryDetector{} + +func newRetryDetector(delegates ...retriable) *retryDetector { + return &retryDetector{delegates: delegates} +} + +func (d *retryDetector) ShouldRetry() bool { + for _, delegate := range d.delegates { + if delegate.ShouldRetry() { + return true + } + } + return false +} + +func (d *retryDetector) Reset() { + for _, delegate := range d.delegates { + delegate.Reset() + } +} + +type statusResponseWriter struct { + http.ResponseWriter + + req *http.Request + statusCode int + wasHijacked bool +} + + +func newStatusResponseWriter(w http.ResponseWriter, req *http.Request) *statusResponseWriter { + return &statusResponseWriter{w, req, 0, false} +} + +func (w *statusResponseWriter) WriteHeader(code int) { + w.statusCode = code + w.ResponseWriter.WriteHeader(code) +} + +func (w *statusResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) { + requestHijacker, ok := w.ResponseWriter.(http.Hijacker) + if !ok { + return nil, nil, fmt.Errorf("unable to hijack response writer: %T", w.ResponseWriter) + } + + w.wasHijacked = true + return requestHijacker.Hijack() +} + +type hijackProtector struct { + delegate retriable + rw *statusResponseWriter +} + +var _ retriable = &hijackProtector{} + +func newHijackProtector(rw *statusResponseWriter, delegate retriable) *hijackProtector { + return &hijackProtector{delegate, rw} +} + +func (p *hijackProtector) ShouldRetry() bool { + if p.rw.wasHijacked { + return false + } + return p.delegate.ShouldRetry() +} + +func (p *hijackProtector) Reset() { + // no-op +} + +type maxRetries struct { + delegate retriable + counter int + max int +} + +var _ retriable = &maxRetries{} + +func newMaxRetries(delegate retriable, max int) *maxRetries { + return &maxRetries{delegate:delegate, max:max} +} + +func (r *maxRetries) Reset() { + // no-op +} + +func (r *maxRetries) ShouldRetry() bool { + r.counter++ + if r.counter > r.max { + return false + } + + return r.delegate.ShouldRetry() +} + +type hijackResponder struct { + delegate proxy.ErrorResponder + req *http.Request + retry bool +} + +var _ proxy.ErrorResponder = &hijackResponder{} +var _ retriable = &hijackResponder{} + +func newHijackResponder(delegate proxy.ErrorResponder, req *http.Request) *hijackResponder { + return &hijackResponder{delegate: delegate, req: req} +} + +func (hr *hijackResponder) Error(w http.ResponseWriter, r *http.Request, err error) { + // if we can retry the request do not send a response to the client + if !hr.canRetry(err) { + hr.delegate.Error(w, r, err) + return + } + hr.retry = true +} + +func (hr *hijackResponder) Reset() { + hr.retry = false +} + +func (hr *hijackResponder) ShouldRetry() bool { + return hr.retry +} + +func (hr *hijackResponder) canRetry(err error) bool { + if isHTTPVerbRetriable(hr.req) && (knet.IsConnectionReset(err) || knet.IsConnectionRefused(err)) { + return true + } + return false +} + +func isHTTPVerbRetriable(req *http.Request) bool { + return req.Method == "GET" +} \ No newline at end of file diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go new file mode 100644 index 0000000000000..0c03b4e89bc19 --- /dev/null +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go @@ -0,0 +1,187 @@ +package apiserver + +import ( + "crypto/tls" + "golang.org/x/net/websocket" + "k8s.io/apiserver/pkg/authentication/user" + apiregistration "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1" + "k8s.io/utils/pointer" + "net/http" + "net/http/httptest" + "net/url" + "sync/atomic" + "testing" +) + +// TODO: test proxy with an HTTP Client as this would allow to test "NewSingleHostReverseProxy" +//func TestProxyRetriesHTTPClient(t *testing.T) { } + +func TestProxyRetries(t *testing.T) { + testcases := map[string]struct { + APIService *apiregistration.APIService + StartBackend bool + BackendCustomHandler func(http.ResponseWriter, *http.Request) + ExpectError bool + ExpectCalled bool + ExpectServiceResolverCounter int + }{ + "retry when connection was refused": { + APIService: &apiregistration.APIService{ + Spec: apiregistration.APIServiceSpec{ + CABundle: testCACrt, + Group: "mygroup", + Version: "v1", + Service: &apiregistration.ServiceReference{Name: "test-service", Namespace: "test-ns", Port: pointer.Int32Ptr(443)}, + }, + Status: apiregistration.APIServiceStatus{ + Conditions: []apiregistration.APIServiceCondition{ + {Type: apiregistration.Available, Status: apiregistration.ConditionTrue}, + }, + }, + }, + ExpectError: true, + ExpectCalled: false, + ExpectServiceResolverCounter: 4, + }, + "no retry on proxy upgrade error (hijacked connections are not retriable)": { + APIService: &apiregistration.APIService{ + Spec: apiregistration.APIServiceSpec{ + CABundle: testCACrt, + Group: "mygroup", + Version: "v1", + Service: &apiregistration.ServiceReference{Name: "test-service", Namespace: "test-ns", Port: pointer.Int32Ptr(443)}, + }, + Status: apiregistration.APIServiceStatus{ + Conditions: []apiregistration.APIServiceCondition{ + {Type: apiregistration.Available, Status: apiregistration.ConditionTrue}, + }, + }, + }, + BackendCustomHandler: func(w http.ResponseWriter, req *http.Request) { + // this handler will cause proxy upgrade error + w.WriteHeader(http.StatusInternalServerError) + return + }, + StartBackend: true, + ExpectError: true, + ExpectCalled: false, + ExpectServiceResolverCounter: 1, + }, + /* + "TODO: fix me rety on io.EOF when connecting to proxy": { + APIService: &apiregistration.APIService{ + Spec: apiregistration.APIServiceSpec{ + CABundle: testCACrt, + Group: "mygroup", + Version: "v1", + Service: &apiregistration.ServiceReference{Name: "test-service", Namespace: "test-ns", Port: pointer.Int32Ptr(443)}, + }, + Status: apiregistration.APIServiceStatus{ + Conditions: []apiregistration.APIServiceCondition{ + {Type: apiregistration.Available, Status: apiregistration.ConditionTrue}, + }, + }, + }, + BackendCustomHandler: func(w http.ResponseWriter, req *http.Request) { + // TODO: this handler causes IO.EOF error which in not consider as retriable ATM + w.WriteHeader(50) + return + }, + StartBackend: true, + ExpectCalled: false, + ExpectServiceResolverCounter: 1, + },*/ + // TODO: happy path - no retries + } + + for k, tc := range testcases { + tcName := k + path := "/apis/" + tc.APIService.Spec.Group + "/" + tc.APIService.Spec.Version + "/foo" + timesCalled := int32(0) + + func() { // Cleanup after each test case. + backendHandler := http.NewServeMux() + if tc.BackendCustomHandler != nil { + backendHandler.HandleFunc(path, tc.BackendCustomHandler) + } else { + backendHandler.Handle(path, websocket.Handler(func(ws *websocket.Conn) { + atomic.AddInt32(×Called, 1) + defer ws.Close() + body := make([]byte, 5) + ws.Read(body) + ws.Write([]byte("hello " + string(body))) + })) + } + + backendServer := httptest.NewUnstartedServer(backendHandler) + cert, err := tls.X509KeyPair(svcCrt, svcKey) + if err != nil { + t.Errorf("https (valid hostname): %v", err) + return + } + backendServer.TLS = &tls.Config{Certificates: []tls.Certificate{cert}} + if tc.StartBackend { + backendServer.StartTLS() + defer backendServer.Close() + } + + defer func() { + if called := atomic.LoadInt32(×Called) > 0; called != tc.ExpectCalled { + t.Errorf("%s: expected called=%v, got %v", tcName, tc.ExpectCalled, called) + } + }() + + serverURL, _ := url.Parse(backendServer.URL) + proxyHandler := &proxyHandler{ + serviceResolver: &mockedRouterWithCounter{&mockedRouter{destinationHost: serverURL.Host}, 0}, + proxyTransport: &http.Transport{}, + } + proxyHandler.updateAPIService(tc.APIService) + aggregator := httptest.NewServer(contextHandler(proxyHandler, &user.DefaultInfo{Name: "username"})) + defer aggregator.Close() + + ws, err := websocket.Dial("ws://"+aggregator.Listener.Addr().String()+path, "", "http://127.0.0.1/") + if err != nil { + if !tc.ExpectError { + t.Errorf("%s: websocket dial err: %s", tcName, err) + } + actualRetries := proxyHandler.serviceResolver.(*mockedRouterWithCounter).counter + if tc.ExpectServiceResolverCounter != actualRetries { + t.Errorf("expected %d retries but got %d", tc.ExpectServiceResolverCounter, actualRetries) + } + return + } + defer ws.Close() + if tc.ExpectError { + t.Errorf("%s: expected websocket error, got none", tcName) + return + } + + if _, err := ws.Write([]byte("world")); err != nil { + t.Errorf("%s: write err: %s", tcName, err) + return + } + + response := make([]byte, 20) + n, err := ws.Read(response) + if err != nil { + t.Errorf("%s: read err: %s", tcName, err) + return + } + if e, a := "hello world", string(response[0:n]); e != a { + t.Errorf("%s: expected '%#v', got '%#v'", tcName, e, a) + return + } + }() + } +} + +type mockedRouterWithCounter struct { + delegate *mockedRouter + counter int +} + +func (r *mockedRouterWithCounter) ResolveEndpoint(namespace, name string, port int32) (*url.URL, error) { + r.counter++ + return r.delegate.ResolveEndpoint(name, name, port) +} From 6f6ae3f1d97492e84e30ebc13c0a00e6fbd9e221 Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Mon, 30 Mar 2020 18:43:14 +0200 Subject: [PATCH 2/8] ResolveEndpoint: considers already visited EPs Date: Mon May 8 12:21:14 2020 +0200 --- .../k8s.io/apiserver/pkg/util/proxy/proxy.go | 35 ++++- .../apiserver/pkg/util/proxy/proxy_test.go | 134 ++++++++++++++++++ .../pkg/apiserver/dynamic_resolver.go | 3 + .../pkg/apiserver/handler_proxy.go | 30 ++-- 4 files changed, 188 insertions(+), 14 deletions(-) create mode 100644 staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go diff --git a/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy.go b/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy.go index f7dd703a674b3..7ce8503e612c1 100644 --- a/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy.go +++ b/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy.go @@ -25,6 +25,7 @@ import ( "k8s.io/api/core/v1" "k8s.io/apimachinery/pkg/api/errors" + "k8s.io/apimachinery/pkg/util/sets" listersv1 "k8s.io/client-go/listers/core/v1" ) @@ -39,7 +40,8 @@ func findServicePort(svc *v1.Service, port int32) (*v1.ServicePort, error) { } // ResourceLocation returns a URL to which one can send traffic for the specified service. -func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, namespace, id string, port int32) (*url.URL, error) { +// TODO: update desc +func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, namespace, id string, port int32, seenEndpoints ...*url.URL) (*url.URL, error) { svc, err := services.Services(namespace).Get(id) if err != nil { return nil, err @@ -68,6 +70,21 @@ func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.Endpo // Pick a random Subset to start searching from. ssSeed := rand.Intn(len(eps.Subsets)) + + seenEndpointsToAddressesFn := func(scheme, port string) (sets.String, error) { + ret := sets.String{} + for _, ep := range seenEndpoints { + if ep.Scheme == scheme && ep.Port() == port { + ip, _, err := net.SplitHostPort(ep.Host) + if err != nil { + return nil, err + } + ret.Insert(ip) + } + } + return ret, nil + } + // Find a Subset that has the port. for ssi := 0; ssi < len(eps.Subsets); ssi++ { ss := &eps.Subsets[(ssSeed+ssi)%len(eps.Subsets)] @@ -77,8 +94,22 @@ func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.Endpo for i := range ss.Ports { if ss.Ports[i].Name == svcPort.Name { // Pick a random address. - ip := ss.Addresses[rand.Intn(len(ss.Addresses))].IP port := int(ss.Ports[i].Port) + seenAddresses, err := seenEndpointsToAddressesFn("https", strconv.Itoa(port)) + if err != nil { + return nil, err + } + availablePoolOfAddresses := []string{} + for _, ep := range ss.Addresses { + if seenAddresses.Has(ep.IP) { + continue + } + availablePoolOfAddresses = append(availablePoolOfAddresses, ep.IP) + } + if len(availablePoolOfAddresses) == 0 { + continue + } + ip := availablePoolOfAddresses[rand.Intn(len(availablePoolOfAddresses))] return &url.URL{ Scheme: "https", Host: net.JoinHostPort(ip, strconv.Itoa(port)), diff --git a/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy_test.go b/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy_test.go index 9539e73b020ba..523a2883da29e 100644 --- a/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy_test.go +++ b/staging/src/k8s.io/apiserver/pkg/util/proxy/proxy_test.go @@ -23,10 +23,144 @@ import ( "k8s.io/api/core/v1" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/util/intstr" + "k8s.io/apimachinery/pkg/util/sets" v1listers "k8s.io/client-go/listers/core/v1" "k8s.io/client-go/tools/cache" ) +func TestResolveWithSeenEndpoints(t *testing.T) { + type expectation struct { + urls sets.String + error bool + } + + matchingEndpoints := func(svc *v1.Service) []*v1.Endpoints { + ports := []v1.EndpointPort{} + for _, p := range svc.Spec.Ports { + if p.TargetPort.Type != intstr.Int { + continue + } + ports = append(ports, v1.EndpointPort{Name: p.Name, Port: p.TargetPort.IntVal}) + } + + return []*v1.Endpoints{{ + ObjectMeta: metav1.ObjectMeta{Namespace: svc.Namespace, Name: svc.Name}, + Subsets: []v1.EndpointSubset{ + { + Addresses: []v1.EndpointAddress{ + {Hostname: "dummy-host-1", IP: "192.168.1.1"}, + {Hostname: "dummy-host-2", IP: "192.168.1.2"}, + {Hostname: "dummy-host-3", IP: "192.168.1.3"}, + }, + Ports: ports, + }, + }, + }} + } + + scenarios := []struct { + name string + services []*v1.Service + endpoints func(svc *v1.Service) []*v1.Endpoints + seenURLs []*url.URL + expectedValues expectation + }{ + { + name: "cluster ip - clean slate", + services: []*v1.Service{ + { + ObjectMeta: metav1.ObjectMeta{Namespace: "one", Name: "alfa"}, + Spec: v1.ServiceSpec{ + Type: v1.ServiceTypeClusterIP, + ClusterIP: "hit", + Ports: []v1.ServicePort{ + {Name: "https", Port: 443, TargetPort: intstr.FromInt(1443)}, + {Port: 1234, TargetPort: intstr.FromInt(1234)}, + }, + }, + }, + }, + endpoints: matchingEndpoints, + expectedValues: expectation{sets.NewString("https://192.168.1.1:1443", "https://192.168.1.2:1443", "https://192.168.1.3:1443"), false}, + }, + { + name: "cluster ip - with seen EP", + services: []*v1.Service{ + { + ObjectMeta: metav1.ObjectMeta{Namespace: "one", Name: "alfa"}, + Spec: v1.ServiceSpec{ + Type: v1.ServiceTypeClusterIP, + ClusterIP: "hit", + Ports: []v1.ServicePort{ + {Name: "https", Port: 443, TargetPort: intstr.FromInt(1443)}, + {Port: 1234, TargetPort: intstr.FromInt(1234)}, + }, + }, + }, + }, + endpoints: matchingEndpoints, + seenURLs: []*url.URL{{Scheme: "https", Host: "192.168.1.2:1443"}}, + expectedValues: expectation{sets.NewString("https://192.168.1.1:1443", "https://192.168.1.3:1443"), false}, + }, + { + name: "cluster ip - all seen", + services: []*v1.Service{ + { + ObjectMeta: metav1.ObjectMeta{Namespace: "one", Name: "alfa"}, + Spec: v1.ServiceSpec{ + Type: v1.ServiceTypeClusterIP, + ClusterIP: "hit", + Ports: []v1.ServicePort{ + {Name: "https", Port: 443, TargetPort: intstr.FromInt(1443)}, + {Port: 1234, TargetPort: intstr.FromInt(1234)}, + }, + }, + }, + }, + endpoints: matchingEndpoints, + expectedValues: expectation{sets.NewString(), true}, + seenURLs: []*url.URL{{Scheme: "https", Host: "192.168.1.1:1443"}, {Scheme: "https", Host: "192.168.1.2:1443"}, {Scheme: "https", Host: "192.168.1.3:1443"}}, + }, + // TODO: add more cases + } + + for _, scenario := range scenarios { + t.Run(scenario.name, func(t *testing.T) { + serviceCache := cache.NewIndexer(cache.MetaNamespaceKeyFunc, cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc}) + serviceLister := v1listers.NewServiceLister(serviceCache) + for i := range scenario.services { + if err := serviceCache.Add(scenario.services[i]); err != nil { + t.Fatalf("%s unexpected service add error: %v", scenario.name, err) + } + } + + endpointCache := cache.NewIndexer(cache.MetaNamespaceKeyFunc, cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc}) + endpointLister := v1listers.NewEndpointsLister(endpointCache) + if scenario.endpoints != nil { + for _, svc := range scenario.services { + for _, ep := range scenario.endpoints(svc) { + if err := endpointCache.Add(ep); err != nil { + t.Fatalf("%s unexpected endpoint add error: %v", scenario.name, err) + } + } + } + } + + url, err := ResolveEndpoint(serviceLister, endpointLister, "one", "alfa", 443, scenario.seenURLs...) + switch { + case err == nil && scenario.expectedValues.error: + t.Error("expected an error, got none") + case err != nil && scenario.expectedValues.error: + // ignore + case err != nil: + t.Errorf("unexpected error: %v", err) + case !scenario.expectedValues.urls.Has(url.String()): + t.Fatalf("unexpected %q URL returned", url.String()) + } + }) + } +} + func TestResolve(t *testing.T) { matchingEndpoints := func(svc *v1.Service) []*v1.Endpoints { ports := []v1.EndpointPort{} diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go new file mode 100644 index 0000000000000..9e61c5f5067f2 --- /dev/null +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go @@ -0,0 +1,3 @@ +package apiserver + + diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go index 1cefab780989e..d3c46a053554f 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go @@ -112,6 +112,7 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { // TODO: to builder pattern retryManager := newHijackProtector(w.(*statusResponseWriter), newMaxRetries(newRetryDetector(errRsp), 3)) + usedEPs := []*url.URL{} for { // TODO: do we have to clone the req ? // TODO: detect disconnected client @@ -120,7 +121,10 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { // TODO: what to report ? // - success, failure // - response time - r.serveHTTP(w, req, errRsp) + ep := r.serveHTTP(w, req, errRsp, usedEPs) + if ep != nil { + usedEPs = append(usedEPs, ep) + } // TODO: add logs // TODO: backoff, jitter @@ -137,37 +141,39 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { } } -func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errResponder proxy.ErrorResponder) { +func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errResponder proxy.ErrorResponder, usedEPs []*url.URL) *url.URL { value := r.handlingInfo.Load() if value == nil { r.localDelegate.ServeHTTP(w, req) - return + return nil } handlingInfo := value.(proxyHandlingInfo) if handlingInfo.local { if r.localDelegate == nil { http.Error(w, "", http.StatusNotFound) - return + return nil } + // TODO: is localDelegate special? e.g. no retries ? r.localDelegate.ServeHTTP(w, req) - return + return nil } + // TODO: rework serviceAvailable - maybe it's not needed anymore if !handlingInfo.serviceAvailable { // TODO: retry proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) - return + return nil } if handlingInfo.transportBuildingError != nil { proxyError(w, req, handlingInfo.transportBuildingError.Error(), http.StatusInternalServerError) - return + return nil } user, ok := genericapirequest.UserFrom(req.Context()) if !ok { proxyError(w, req, "missing user", http.StatusInternalServerError) - return + return nil } // write a new location based on the existing request pointed at the target service @@ -176,9 +182,8 @@ func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errRe rloc, err := r.serviceResolver.ResolveEndpoint(handlingInfo.serviceNamespace, handlingInfo.serviceName, handlingInfo.servicePort) if err != nil { klog.Errorf("error resolving %s/%s: %v", handlingInfo.serviceNamespace, handlingInfo.serviceName, err) - // TODO: retry proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) - return + return nil } location.Host = rloc.Host location.Path = req.URL.Path @@ -189,14 +194,14 @@ func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errRe if handlingInfo.proxyRoundTripper == nil { proxyError(w, req, "", http.StatusNotFound) - return + return nil } // we need to wrap the roundtripper in another roundtripper which will apply the front proxy headers proxyRoundTripper, upgrade, err := maybeWrapForConnectionUpgrades(handlingInfo.restConfig, handlingInfo.proxyRoundTripper, req) if err != nil { proxyError(w, req, err.Error(), http.StatusInternalServerError) - return + return nil } proxyRoundTripper = transport.NewAuthProxyRoundTripper(user.GetName(), user.GetGroups(), user.GetExtra(), proxyRoundTripper) @@ -210,6 +215,7 @@ func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errRe handler := proxy.NewUpgradeAwareHandler(location, proxyRoundTripper, true, upgrade, errResponder) handler.ServeHTTP(w, newReq) + return rloc } // newRequestForProxy returns a shallow copy of the original request with a context that may include a timeout for discovery requests From 2c09ed59d7f6861bac35f3b0899c0048f5a3d95f Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Fri, 8 May 2020 12:34:14 +0200 Subject: [PATCH 3/8] wires ServiceResolverWrapper and ServiceReporter allows encapsulating possible implementations: - the old implementation - a new implementation that only supports retries (ServiceResolverWithVisited) - a new implementation that supports retries, health reporting and picking up the best possible EP at the given time by examining weights assigned to EPs (ServiceResolverWithVisited, ServiceResolverWithCollector, FailureDetector) Date: Tue May 08 12:31:08 2020 +0200 --- ...esolver.go => dynamic_service_resolver.go} | 0 .../pkg/apiserver/handler_proxy.go | 78 ++++++++++++++----- .../pkg/apiserver/resolvers.go | 13 ++++ .../pkg/apiserver/retry_detector.go | 30 ++++++- .../pkg/apiserver/retry_detector_test.go | 3 + 5 files changed, 102 insertions(+), 22 deletions(-) rename staging/src/k8s.io/kube-aggregator/pkg/apiserver/{dynamic_resolver.go => dynamic_service_resolver.go} (100%) diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go similarity index 100% rename from staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_resolver.go rename to staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go index d3c46a053554f..cae6d3fdaca86 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go @@ -112,36 +112,74 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { // TODO: to builder pattern retryManager := newHijackProtector(w.(*statusResponseWriter), newMaxRetries(newRetryDetector(errRsp), 3)) - usedEPs := []*url.URL{} + visitedEPs := []*url.URL{} for { - // TODO: do we have to clone the req ? - // TODO: detect disconnected client - // TODO: pick up a different EP on retry - // TODO: always report the status to the service resolver - this will influence available EPs pool - // TODO: what to report ? - // - success, failure - // - response time - ep := r.serveHTTP(w, req, errRsp, usedEPs) - if ep != nil { - usedEPs = append(usedEPs, ep) - } - - // TODO: add logs - // TODO: backoff, jitter - if !retryManager.ShouldRetry(){ + done := func() bool { + serviceHit := false + defer func() { + // TODO: always report the status to the service resolver - this will influence available EPs pool + // TODO: what to report ? + // - success, failure + // - response time + if serviceHit { + r.serviceReporter(w.(*statusResponseWriter).statusCode, retryManager.LastKnownError()) + } + }() + // TODO: do we have to clone the req ? + // TODO: detect disconnected client + visitedEP := r.serveHTTP(w, req, errRsp, r.serviceResolverWrapper(visitedEPs)) + if visitedEP != nil { + visitedEPs = append(visitedEPs, visitedEP) + serviceHit = true + } + + // TODO: add logs + // TODO: backoff, jitter + if !retryManager.ShouldRetry() { + return false + } + retryManager.Reset() + return true + }() + if !done { break } - retryManager.Reset() } - if w.(*statusResponseWriter).statusCode == 0 && !w.(*statusResponseWriter).wasHijacked{ + if w.(*statusResponseWriter).statusCode == 0 && !w.(*statusResponseWriter).wasHijacked { // TODO: send HTTP 503 if the error is retriable // otherwise send HTTP 500 proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) } } -func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errResponder proxy.ErrorResponder, usedEPs []*url.URL) *url.URL { +// TODO: come up with better abstractions +func (r *proxyHandler) serviceReporter(httpStatusCode int, lastKnownError error) { + if serviceReporter, ok := r.serviceResolver.(ServiceResolverWithCollector); ok { + select { + case serviceReporter.Collector() <- struct{}{}: + default: + // TODO: log that we didn't report + } + } +} + +// I am not sure what it takes to add a new feature to the aggregator. Maybe the whole thing will be hidden behind a feature flag, maybe not. +// Thus I decided to provide this wrapper as a way to encapsulate possible implementations. That is: +// - the old implementation +// - a new implementation that only supports retries (ServiceResolverWithVisited) +// - a new implementation that supports retries and picking up the best possible EP at the given time by examining weights assigned to EPs (ServiceResolverWithVisited, ServiceResolverWithCollector, FailureDetector) +func (r *proxyHandler) serviceResolverWrapper(visitedEPs []*url.URL) func(namespace, name string, port int32) (*url.URL, error) { + serviceResolverWrapper := func(namespace, name string, port int32) (*url.URL, error) { + if serviceResolver, ok := r.serviceResolver.(ServiceResolverWithVisited); ok { + return serviceResolver.ResolveEndpointWithVisited(namespace, name, port, visitedEPs) + } + return r.serviceResolver.ResolveEndpoint(namespace, name, port) + } + return serviceResolverWrapper +} + +func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errResponder proxy.ErrorResponder, serviceResolverFn func(namespace, name string, port int32) (*url.URL, error)) *url.URL { value := r.handlingInfo.Load() if value == nil { r.localDelegate.ServeHTTP(w, req) @@ -179,7 +217,7 @@ func (r *proxyHandler) serveHTTP(w http.ResponseWriter, req *http.Request, errRe // write a new location based on the existing request pointed at the target service location := &url.URL{} location.Scheme = "https" - rloc, err := r.serviceResolver.ResolveEndpoint(handlingInfo.serviceNamespace, handlingInfo.serviceName, handlingInfo.servicePort) + rloc, err := serviceResolverFn(handlingInfo.serviceNamespace, handlingInfo.serviceName, handlingInfo.servicePort) if err != nil { klog.Errorf("error resolving %s/%s: %v", handlingInfo.serviceNamespace, handlingInfo.serviceName, err) proxyError(w, req, "service unavailable", http.StatusServiceUnavailable) diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go index 74bcb24d98762..cca38a195c1b0 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go @@ -28,6 +28,19 @@ type ServiceResolver interface { ResolveEndpoint(namespace, name string, port int32) (*url.URL, error) } +// ServiceResolverWithCollector extends standard ServiceResolver by providing a method for health reporting. +type ServiceResolverWithCollector interface { + // Collector a channel for sending EndpointSamples for further processing and evaluation. + Collector() chan <- struct{} +} + +// ServiceResolverWithVisited extends standard ServiceResolver by providing a method for supporting retry mechanisms +type ServiceResolverWithVisited interface { + // ResolveEndpointWithVisited resolves an endpoint excluding already visited ones. + // Facilitates supporting retry mechanisms. + ResolveEndpointWithVisited(namespace, name string, port int32, visitedEPs []*url.URL) (*url.URL, error) +} + // NewEndpointServiceResolver returns a ServiceResolver that chooses one of the // service's endpoints. func NewEndpointServiceResolver(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister) ServiceResolver { diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go index ed16baa8c7899..82db656c4c284 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go @@ -13,6 +13,7 @@ import ( type retriable interface { ShouldRetry() bool Reset() + LastKnownError() error } type retryDetector struct { @@ -40,6 +41,17 @@ func (d *retryDetector) Reset() { } } +func (d *retryDetector) LastKnownError() error { + for _, delegate := range d.delegates { + err := delegate.LastKnownError() + if err != nil { + return err + } + } + + return nil +} + type statusResponseWriter struct { http.ResponseWriter @@ -87,7 +99,11 @@ func (p *hijackProtector) ShouldRetry() bool { } func (p *hijackProtector) Reset() { - // no-op + p.delegate.Reset() +} + +func (p *hijackProtector) LastKnownError() error { + return p.delegate.LastKnownError() } type maxRetries struct { @@ -103,7 +119,7 @@ func newMaxRetries(delegate retriable, max int) *maxRetries { } func (r *maxRetries) Reset() { - // no-op + r.delegate.Reset() } func (r *maxRetries) ShouldRetry() bool { @@ -115,10 +131,15 @@ func (r *maxRetries) ShouldRetry() bool { return r.delegate.ShouldRetry() } +func (r *maxRetries) LastKnownError() error { + return r.delegate.LastKnownError() +} + type hijackResponder struct { delegate proxy.ErrorResponder req *http.Request retry bool + lastKnownError error } var _ proxy.ErrorResponder = &hijackResponder{} @@ -139,12 +160,17 @@ func (hr *hijackResponder) Error(w http.ResponseWriter, r *http.Request, err err func (hr *hijackResponder) Reset() { hr.retry = false + hr.lastKnownError = nil } func (hr *hijackResponder) ShouldRetry() bool { return hr.retry } +func (hr *hijackResponder) LastKnownError() error { + return hr.lastKnownError +} + func (hr *hijackResponder) canRetry(err error) bool { if isHTTPVerbRetriable(hr.req) && (knet.IsConnectionReset(err) || knet.IsConnectionRefused(err)) { return true diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go index 0c03b4e89bc19..3c8822ac0a73f 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector_test.go @@ -16,6 +16,9 @@ import ( // TODO: test proxy with an HTTP Client as this would allow to test "NewSingleHostReverseProxy" //func TestProxyRetriesHTTPClient(t *testing.T) { } +// TODO: test serviceReporter +// TODO: test serviceResolverWrapper + func TestProxyRetries(t *testing.T) { testcases := map[string]struct { APIService *apiregistration.APIService From 49252b40e4a89f7961240a019868b775639fd1da Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Fri, 8 May 2020 14:48:47 +0200 Subject: [PATCH 4/8] WIP: wire FailureDetector --- cmd/kube-apiserver/app/server.go | 27 +++++++-- .../pkg/apiserver/dynamic_service_resolver.go | 58 +++++++++++++++++++ .../pkg/apiserver/handler_proxy.go | 1 + 3 files changed, 81 insertions(+), 5 deletions(-) diff --git a/cmd/kube-apiserver/app/server.go b/cmd/kube-apiserver/app/server.go index 2ad5309f22d7f..d1adfc72c9e9a 100644 --- a/cmd/kube-apiserver/app/server.go +++ b/cmd/kube-apiserver/app/server.go @@ -29,9 +29,11 @@ import ( "strconv" "strings" "time" + gcontext "context" "github.com/go-openapi/spec" "github.com/spf13/cobra" + failuredetector "github.com/p0lyn0mial/failure-detector" extensionsapiserver "k8s.io/apiextensions-apiserver/pkg/apiserver" v1 "k8s.io/apimachinery/pkg/apis/meta/v1" @@ -281,7 +283,7 @@ func CreateKubeAPIServerConfig( []admission.PluginInitializer, error, ) { - genericConfig, versionedInformers, insecureServingInfo, serviceResolver, pluginInitializers, admissionPostStartHook, storageFactory, err := buildGenericConfig(s.ServerRunOptions, proxyTransport) + genericConfig, versionedInformers, insecureServingInfo, serviceResolver, serviceResolverPostStartHook, pluginInitializers, admissionPostStartHook, storageFactory, err := buildGenericConfig(s.ServerRunOptions, proxyTransport) if err != nil { return nil, nil, nil, nil, err } @@ -375,6 +377,12 @@ func CreateKubeAPIServerConfig( return nil, nil, nil, nil, err } + if serviceResolverPostStartHook != nil { + if err := config.GenericConfig.AddPostStartHook("start-kube-apiserver-service-resolver", serviceResolverPostStartHook); err != nil { + return nil, nil, nil, nil, err + } + } + if nodeTunneler != nil { // Use the nodeTunneler's dialer to connect to the kubelet config.ExtraConfig.KubeletClientConfig.Dial = nodeTunneler.Dial @@ -422,6 +430,7 @@ func buildGenericConfig( versionedInformers clientgoinformers.SharedInformerFactory, insecureServingInfo *genericapiserver.DeprecatedInsecureServingInfo, serviceResolver aggregatorapiserver.ServiceResolver, + serviceResolverPostStartHook genericapiserver.PostStartHookFunc, pluginInitializers []admission.PluginInitializer, admissionPostStartHook genericapiserver.PostStartHookFunc, storageFactory *serverstorage.DefaultStorageFactory, @@ -518,7 +527,7 @@ func buildGenericConfig( LoopbackClientConfig: genericConfig.LoopbackClientConfig, CloudConfigFile: s.CloudProvider.CloudConfigFile, } - serviceResolver = buildServiceResolver(s.EnableAggregatorRouting, genericConfig.LoopbackClientConfig.Host, versionedInformers) + serviceResolver, serviceResolverPostStartHook = buildServiceResolver(s.EnableAggregatorRouting, genericConfig.LoopbackClientConfig.Host, versionedInformers) authInfoResolverWrapper := webhook.NewDefaultAuthenticationInfoResolverWrapper(proxyTransport, genericConfig.EgressSelector, genericConfig.LoopbackClientConfig) @@ -725,12 +734,20 @@ func Complete(s *options.ServerRunOptions) (completedServerRunOptions, error) { return options, nil } -func buildServiceResolver(enabledAggregatorRouting bool, hostname string, informer clientgoinformers.SharedInformerFactory) webhook.ServiceResolver { +func buildServiceResolver(enabledAggregatorRouting bool, hostname string, informer clientgoinformers.SharedInformerFactory) (webhook.ServiceResolver, genericapiserver.PostStartHookFunc) { var serviceResolver webhook.ServiceResolver + var serviceResolverPostStartHook func(context genericapiserver.PostStartHookContext) error if enabledAggregatorRouting { - serviceResolver = aggregatorapiserver.NewEndpointServiceResolver( + fd := failuredetector.NewDefaultFailureDetector() + serviceResolverPostStartHook = func(context genericapiserver.PostStartHookContext) error { + // TODO: wire context to PostStartHookContext or change the method signature to accept a chan + go fd.Run(gcontext.TODO()) + return nil + } + serviceResolver = aggregatorapiserver.NewEndpointServiceResolverWithFailureDetector( informer.Core().V1().Services().Lister(), informer.Core().V1().Endpoints().Lister(), + fd, ) } else { serviceResolver = aggregatorapiserver.NewClusterIPServiceResolver( @@ -741,7 +758,7 @@ func buildServiceResolver(enabledAggregatorRouting bool, hostname string, inform if localHost, err := url.Parse(hostname); err == nil { serviceResolver = aggregatorapiserver.NewLoopbackServiceResolver(serviceResolver, localHost) } - return serviceResolver + return serviceResolver, serviceResolverPostStartHook } func getServiceIPAndRanges(serviceClusterIPRanges string) (net.IP, net.IPNet, net.IPNet, error) { diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go index 9e61c5f5067f2..6f27cb7850f8a 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go @@ -1,3 +1,61 @@ package apiserver +import ( + "net/url" + + failuredetector "github.com/p0lyn0mial/failure-detector" + + listersv1 "k8s.io/client-go/listers/core/v1" + "k8s.io/apiserver/pkg/util/proxy" +) + +// FailureDetector helps to assess the health conditions of endpoints. +// +// It does that by providing `Collector()` method for collecting samples and `XYZ()` for querying the current health of endpoints for a given service. +type FailureDetector interface { + // Collector exposes a channel for collecting EndpointSamples + Collector() chan<- *failuredetector.EndpointSample +} + +// NewEndpointServiceResolverWithFailureDetector returns a service resolver with support for retry mechanisms, health reporting and failure detection +func NewEndpointServiceResolverWithFailureDetector(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, failureDetector FailureDetector) ServiceResolver { + return &serviceResolver{ + services: services, + endpoints: endpoints, + failureDetector: failureDetector, + } +} + +type serviceResolver struct { + services listersv1.ServiceLister + endpoints listersv1.EndpointsLister + failureDetector FailureDetector +} + +// ResolveEndpoint resolves (randomly) an endpoint to a given service. +// +// Note: +// Kube uses one service resolver for webhooks and the aggregator this method satisfies webhook.ServiceResolver interface +func (r *serviceResolver) ResolveEndpoint(namespace, name string, port int32) (*url.URL, error) { + return proxy.ResolveEndpoint(r.services, r.endpoints, namespace, name, port) +} + +// ResolveEndpointWithVisited resolves an endpoint excluding already visited ones. +// Facilitates supporting retry mechanisms. +func (r *serviceResolver) ResolveEndpointWithVisited(namespace, name string, port int32, visitedEPs []*url.URL) (*url.URL, error) { + // TODO: + // 1. query failureDetector to get the current list of EPs for the given service + // 2. exclude already visited ones + // 3. get all possible EPs for the service from the service resolver excluding already visited ones + // 4. assign weights to EPs from 3 based on the input returned from 2 + // 5. sort the list from 4 by weight - new EP should get the weight equal 1 (indicates a healthy condition) + // 6. pick one EP randomly taking EPs's weights into account from the list obtained in 5 + // 7. return EP from 6 + return proxy.ResolveEndpoint(r.services, r.endpoints, namespace, name, port, visitedEPs...) +} + +// Collector exposes a channel for sending EndpointSamples for further processing and evaluation. +func (r *serviceResolver) Collector() chan <- *failuredetector.EndpointSample { + return r.failureDetector.Collector() +} diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go index cae6d3fdaca86..f4c35688511f0 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go @@ -121,6 +121,7 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { // TODO: what to report ? // - success, failure // - response time + // TODO: what if the last known error is actually unknown and status code is >= 500 if serviceHit { r.serviceReporter(w.(*statusResponseWriter).statusCode, retryManager.LastKnownError()) } From e71cd7a75833fd49f33b5a871e2e253f0dd7fe91 Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Mon, 11 May 2020 14:22:40 +0200 Subject: [PATCH 5/8] implements ResolveEndpointWithVisited --- .../pkg/apiserver/dynamic_service_resolver.go | 89 +++++++-- .../dynamic_service_resolver_test.go | 181 ++++++++++++++++++ 2 files changed, 253 insertions(+), 17 deletions(-) create mode 100644 staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver_test.go diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go index 6f27cb7850f8a..a3deedb71001a 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver.go @@ -1,34 +1,40 @@ package apiserver import ( + "fmt" "net/url" + "sort" failuredetector "github.com/p0lyn0mial/failure-detector" - listersv1 "k8s.io/client-go/listers/core/v1" + "k8s.io/apimachinery/pkg/api/errors" "k8s.io/apiserver/pkg/util/proxy" + listersv1 "k8s.io/client-go/listers/core/v1" ) // FailureDetector helps to assess the health conditions of endpoints. // // It does that by providing `Collector()` method for collecting samples and `XYZ()` for querying the current health of endpoints for a given service. type FailureDetector interface { - // Collector exposes a channel for collecting EndpointSamples - Collector() chan<- *failuredetector.EndpointSample + // Collector exposes a channel for collecting EndpointSamples + Collector() chan<- *failuredetector.EndpointSample + + // EndpointStatus returns the current status of the given endpoint for the given service + EndpointStatus(namespace, service string, url *url.URL) (isHealthy bool, weight float32) } // NewEndpointServiceResolverWithFailureDetector returns a service resolver with support for retry mechanisms, health reporting and failure detection func NewEndpointServiceResolverWithFailureDetector(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, failureDetector FailureDetector) ServiceResolver { return &serviceResolver{ - services: services, - endpoints: endpoints, + services: services, + endpoints: endpoints, failureDetector: failureDetector, } } type serviceResolver struct { - services listersv1.ServiceLister - endpoints listersv1.EndpointsLister + services listersv1.ServiceLister + endpoints listersv1.EndpointsLister failureDetector FailureDetector } @@ -43,19 +49,68 @@ func (r *serviceResolver) ResolveEndpoint(namespace, name string, port int32) (* // ResolveEndpointWithVisited resolves an endpoint excluding already visited ones. // Facilitates supporting retry mechanisms. func (r *serviceResolver) ResolveEndpointWithVisited(namespace, name string, port int32, visitedEPs []*url.URL) (*url.URL, error) { - // TODO: - // 1. query failureDetector to get the current list of EPs for the given service - // 2. exclude already visited ones - // 3. get all possible EPs for the service from the service resolver excluding already visited ones - // 4. assign weights to EPs from 3 based on the input returned from 2 - // 5. sort the list from 4 by weight - new EP should get the weight equal 1 (indicates a healthy condition) - // 6. pick one EP randomly taking EPs's weights into account from the list obtained in 5 - // 7. return EP from 6 - return proxy.ResolveEndpoint(r.services, r.endpoints, namespace, name, port, visitedEPs...) + potentialEndpoints, err := r.remainingEndpoints(namespace, name, port, visitedEPs) + if err != nil { + return nil, err + } + return r.resolveEndpointHealthyPriority(namespace, name, potentialEndpoints) } // Collector exposes a channel for sending EndpointSamples for further processing and evaluation. -func (r *serviceResolver) Collector() chan <- *failuredetector.EndpointSample { +func (r *serviceResolver) Collector() chan<- *failuredetector.EndpointSample { return r.failureDetector.Collector() } +// remainingEndpoints gets all remaining end points for the given service except already visited ones +func (r *serviceResolver) remainingEndpoints(namespace, name string, port int32, visitedEPs []*url.URL) ([]*url.URL, error) { + allNewEndpoints := []*url.URL{} + + for { + // TODO: in the future simply list all EP instead of using ResolveEndpoint which assigns an EP randomly + newEndpoint, err := proxy.ResolveEndpoint(r.services, r.endpoints, namespace, name, port, visitedEPs...) + if err != nil { + break + } + allNewEndpoints = append(allNewEndpoints, newEndpoint) + visitedEPs = append(visitedEPs, newEndpoint) + } + + if len(allNewEndpoints) == 0 { + return nil, errors.NewServiceUnavailable(fmt.Sprintf("no endpoints available for service %q/%q", namespace, name)) + } + + return allNewEndpoints, nil +} + +// weightedEndpoint a helper struct for keeping weight and url together +type weightedEndpoint struct { + url *url.URL + weight float32 +} + +// weightedEndpointsByPriority a helper type for sorting weightedEndpoint by priority +type weightedEndpointsByPriority []*weightedEndpoint + +func (wep weightedEndpointsByPriority) Len() int { return len(wep) } +func (wep weightedEndpointsByPriority) Swap(i, j int) { wep[i], wep[j] = wep[j], wep[i] } +func (wep weightedEndpointsByPriority) Less(i, j int) bool { return wep[i].weight > wep[j].weight } + +// resolveEndpointHealthyPriority pick the best endpoint for the given service from potentialEndpoints +// it does that by querying failure detector, removing unhealthy endpoints and sorting the remaining by priority +func (r *serviceResolver) resolveEndpointHealthyPriority(namespace, name string, potentialEndpoints []*url.URL) (*url.URL, error) { + healthyWeightedEndpoints := weightedEndpointsByPriority{} + + for _, endpoint := range potentialEndpoints { + isHealthy, weight := r.failureDetector.EndpointStatus(namespace, name, endpoint) + if isHealthy { + healthyWeightedEndpoints = append(healthyWeightedEndpoints, &weightedEndpoint{url: endpoint, weight: weight}) + } + } + + sort.Sort(healthyWeightedEndpoints) + + if len(healthyWeightedEndpoints) == 0 { + return nil, errors.NewServiceUnavailable(fmt.Sprintf("no endpoints available for service %q/%q", namespace, name)) + } + return healthyWeightedEndpoints[0].url, nil +} diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver_test.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver_test.go new file mode 100644 index 0000000000000..f920c71534a80 --- /dev/null +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/dynamic_service_resolver_test.go @@ -0,0 +1,181 @@ +package apiserver + +import ( + "net/url" + "testing" + + failuredetector "github.com/p0lyn0mial/failure-detector" + + v1 "k8s.io/api/core/v1" + metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" + "k8s.io/apimachinery/pkg/util/intstr" + v1listers "k8s.io/client-go/listers/core/v1" + "k8s.io/client-go/tools/cache" +) + +func TestEndpointServiceResolverWithFailureDetector(t *testing.T) { + scenarios := []struct { + name string + services []*v1.Service + endpoints func(svc *v1.Service) []*v1.Endpoints + seenURLs []*url.URL + fakeEndpoints []*fakeWeightedEndpoint + expectedValues expectation + }{ + { + name: "an EP with the highest weight wins - no seenURLS", + services: defaultServices(), + endpoints: matchingEndpoints, + fakeEndpoints: []*fakeWeightedEndpoint{ + {url: "https://192.168.1.1:1443", weight: 0.8, healthy: true}, + {url: "https://192.168.1.2:1443", weight: 0.7, healthy: true}, + {url: "https://192.168.1.3:1443", weight: 0.9, healthy: true}, + }, + expectedValues: expectation{"https://192.168.1.3:1443", false}, + }, + + { + name: "an EP with the highest weight wins - with seenURLS", + services: defaultServices(), + endpoints: matchingEndpoints, + seenURLs: []*url.URL{{Scheme: "https", Host: "192.168.1.3:1443"}}, + fakeEndpoints: []*fakeWeightedEndpoint{ + {url: "https://192.168.1.1:1443", weight: 0.8, healthy: true}, + {url: "https://192.168.1.2:1443", weight: 0.7, healthy: true}, + {url: "https://192.168.1.3:1443", weight: 0.9, healthy: true}, + }, + expectedValues: expectation{"https://192.168.1.1:1443", false}, + }, + + { + name: "a healthy EP with the highest weight wins - no seenURLS", + services: defaultServices(), + endpoints: matchingEndpoints, + fakeEndpoints: []*fakeWeightedEndpoint{ + {url: "https://192.168.1.1:1443", weight: 0.8, healthy: true}, + {url: "https://192.168.1.2:1443", weight: 0.7, healthy: true}, + {url: "https://192.168.1.3:1443", weight: 0.9, healthy: false}, + }, + expectedValues: expectation{"https://192.168.1.1:1443", false}, + }, + + { + name: "no healthy endpoints", + services: defaultServices(), + endpoints: matchingEndpoints, + fakeEndpoints: []*fakeWeightedEndpoint{ + {url: "https://192.168.1.1:1443", weight: 0.8, healthy: false}, + {url: "https://192.168.1.2:1443", weight: 0.7, healthy: false}, + {url: "https://192.168.1.3:1443", weight: 0.9, healthy: false}, + }, + expectedValues: expectation{"", true}, + }, + } + + for _, scenario := range scenarios { + t.Run(scenario.name, func(t *testing.T) { + + serviceCache := cache.NewIndexer(cache.MetaNamespaceKeyFunc, cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc}) + serviceLister := v1listers.NewServiceLister(serviceCache) + for i := range scenario.services { + if err := serviceCache.Add(scenario.services[i]); err != nil { + t.Fatalf("%s unexpected service add error: %v", scenario.name, err) + } + } + + endpointCache := cache.NewIndexer(cache.MetaNamespaceKeyFunc, cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc}) + endpointLister := v1listers.NewEndpointsLister(endpointCache) + if scenario.endpoints != nil { + for _, svc := range scenario.services { + for _, ep := range scenario.endpoints(svc) { + if err := endpointCache.Add(ep); err != nil { + t.Fatalf("%s unexpected endpoint add error: %v", scenario.name, err) + } + } + } + } + + target := &serviceResolver{serviceLister, endpointLister, &fakeFailureDetector{scenario.fakeEndpoints}} + url, err := target.ResolveEndpointWithVisited("one", "alfa", 443, scenario.seenURLs) + switch { + case err == nil && scenario.expectedValues.error: + t.Error("expected an error, got none") + case err != nil && scenario.expectedValues.error: + // ignore + case err != nil: + t.Errorf("unexpected error: %v", err) + case scenario.expectedValues.url != url.String(): + t.Fatalf("unexpected %q URL returned", url.String()) + } + }) + } +} + +func defaultServices() []*v1.Service { + return []*v1.Service{ + { + ObjectMeta: metav1.ObjectMeta{Namespace: "one", Name: "alfa"}, + Spec: v1.ServiceSpec{ + Type: v1.ServiceTypeClusterIP, + ClusterIP: "hit", + Ports: []v1.ServicePort{ + {Name: "https", Port: 443, TargetPort: intstr.FromInt(1443)}, + {Port: 1234, TargetPort: intstr.FromInt(1234)}, + }, + }, + }, + } +} + +type expectation struct { + url string + error bool +} + +func matchingEndpoints(svc *v1.Service) []*v1.Endpoints { + ports := []v1.EndpointPort{} + for _, p := range svc.Spec.Ports { + if p.TargetPort.Type != intstr.Int { + continue + } + ports = append(ports, v1.EndpointPort{Name: p.Name, Port: p.TargetPort.IntVal}) + } + + return []*v1.Endpoints{{ + ObjectMeta: metav1.ObjectMeta{Namespace: svc.Namespace, Name: svc.Name}, + Subsets: []v1.EndpointSubset{ + { + Addresses: []v1.EndpointAddress{ + {Hostname: "dummy-host-1", IP: "192.168.1.1"}, + {Hostname: "dummy-host-2", IP: "192.168.1.2"}, + {Hostname: "dummy-host-3", IP: "192.168.1.3"}, + }, + Ports: ports, + }, + }, + }} +} + +type fakeWeightedEndpoint struct { + url string + healthy bool + weight float32 +} + +type fakeFailureDetector struct { + fakeWeightedEndpoints []*fakeWeightedEndpoint +} + +func (fd *fakeFailureDetector) Collector() chan<- *failuredetector.EndpointSample { + return nil +} + +func (fd *fakeFailureDetector) EndpointStatus(namespace, service string, url *url.URL) (isHealthy bool, weight float32) { + for _, fakeEndpoint := range fd.fakeWeightedEndpoints { + if fakeEndpoint.url == url.String() { + return fakeEndpoint.healthy, fakeEndpoint.weight + } + } + + return true, 1.0 +} From 1422debaed011d6974871834fe69e69f4c4c59fb Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Mon, 11 May 2020 15:59:53 +0200 Subject: [PATCH 6/8] fills in serviceReporter --- .../pkg/apiserver/handler_proxy.go | 41 +++++++++++++------ .../pkg/apiserver/resolvers.go | 4 +- 2 files changed, 31 insertions(+), 14 deletions(-) diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go index f4c35688511f0..48708a3c145c9 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go @@ -18,12 +18,15 @@ package apiserver import ( "context" + "fmt" "net/http" "net/url" "strings" "sync/atomic" "time" + failuredetector "github.com/p0lyn0mial/failure-detector" + "k8s.io/apimachinery/pkg/runtime" "k8s.io/apimachinery/pkg/util/httpstream" "k8s.io/apimachinery/pkg/util/httpstream/spdy" @@ -115,23 +118,20 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { visitedEPs := []*url.URL{} for { done := func() bool { - serviceHit := false + var visitedEP *url.URL + defer func() { - // TODO: always report the status to the service resolver - this will influence available EPs pool - // TODO: what to report ? - // - success, failure - // - response time - // TODO: what if the last known error is actually unknown and status code is >= 500 - if serviceHit { - r.serviceReporter(w.(*statusResponseWriter).statusCode, retryManager.LastKnownError()) + if visitedEP != nil { + // TODO: what to report ? + // - response time + r.serviceReporter(visitedEP, w.(*statusResponseWriter).statusCode, retryManager.LastKnownError()) } }() // TODO: do we have to clone the req ? // TODO: detect disconnected client - visitedEP := r.serveHTTP(w, req, errRsp, r.serviceResolverWrapper(visitedEPs)) + visitedEP = r.serveHTTP(w, req, errRsp, r.serviceResolverWrapper(visitedEPs)) if visitedEP != nil { visitedEPs = append(visitedEPs, visitedEP) - serviceHit = true } // TODO: add logs @@ -155,12 +155,27 @@ func (r *proxyHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { } // TODO: come up with better abstractions -func (r *proxyHandler) serviceReporter(httpStatusCode int, lastKnownError error) { +func (r *proxyHandler) serviceReporter(visitedEP *url.URL, httpStatusCode int, lastKnownError error) { if serviceReporter, ok := r.serviceResolver.(ServiceResolverWithCollector); ok { + value := r.handlingInfo.Load() + if value == nil { + // should never happen + klog.Warning("unable to report health stats no handling info for proxy handler") + return + } + handlingInfo := value.(proxyHandlingInfo) + + // create an error if the lastKnownError is unknown but the HTTP Status indicates an error + // TODO: can this ever happen ? + if lastKnownError == nil && httpStatusCode >= 500 { + lastKnownError = fmt.Errorf("%d", httpStatusCode) + } + sample := &failuredetector.EndpointSample{Namespace: handlingInfo.serviceNamespace, Service: handlingInfo.serviceName, URL: visitedEP, Err: lastKnownError} + select { - case serviceReporter.Collector() <- struct{}{}: + case serviceReporter.Collector() <- sample: default: - // TODO: log that we didn't report + klog.Warningf("unable to report health stats (slow chan consumer !) for an endpoint %s in %s/%s, the last known error was %v", visitedEP.String(), handlingInfo.serviceNamespace, handlingInfo.serviceName, lastKnownError) } } } diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go index cca38a195c1b0..e95f414a07f34 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/resolvers.go @@ -19,6 +19,8 @@ package apiserver import ( "net/url" + failuredetector "github.com/p0lyn0mial/failure-detector" + "k8s.io/apiserver/pkg/util/proxy" listersv1 "k8s.io/client-go/listers/core/v1" ) @@ -31,7 +33,7 @@ type ServiceResolver interface { // ServiceResolverWithCollector extends standard ServiceResolver by providing a method for health reporting. type ServiceResolverWithCollector interface { // Collector a channel for sending EndpointSamples for further processing and evaluation. - Collector() chan <- struct{} + Collector() chan<- *failuredetector.EndpointSample } // ServiceResolverWithVisited extends standard ServiceResolver by providing a method for supporting retry mechanisms From c7e212e92a99b76f19182e84c388b5a4e81d0ed5 Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Mon, 11 May 2020 16:21:57 +0200 Subject: [PATCH 7/8] bump(*) --- Godeps/LICENSES | 2046 +++++++++++++++++ cmd/kube-apiserver/app/BUILD | 1 + go.mod | 4 + go.sum | 6 + .../src/k8s.io/apiserver/pkg/util/proxy/BUILD | 2 + staging/src/k8s.io/kube-aggregator/go.mod | 3 + staging/src/k8s.io/kube-aggregator/go.sum | 6 + .../kube-aggregator/pkg/apiserver/BUILD | 9 + vendor/BUILD | 3 + .../p0lyn0mial/batch-working-queue/BUILD | 24 + .../p0lyn0mial/batch-working-queue/LICENSE | 674 ++++++ .../batch_working_queue.go | 73 + .../p0lyn0mial/failure-detector/BUILD | 36 + .../p0lyn0mial/failure-detector/LICENSE | 674 ++++++ .../failure-detector/batch_processor.go | 77 + .../failure-detector/failure_detector.go | 169 ++ .../p0lyn0mial/failure-detector/interfaces.go | 239 ++ .../failure-detector/simple_policy.go | 46 + vendor/github.com/p0lyn0mial/ttl-cache/BUILD | 24 + .../github.com/p0lyn0mial/ttl-cache/LICENSE | 674 ++++++ .../p0lyn0mial/ttl-cache/eviction_store.go | 85 + vendor/modules.txt | 6 + 22 files changed, 4881 insertions(+) create mode 100644 vendor/github.com/p0lyn0mial/batch-working-queue/BUILD create mode 100644 vendor/github.com/p0lyn0mial/batch-working-queue/LICENSE create mode 100644 vendor/github.com/p0lyn0mial/batch-working-queue/batch_working_queue.go create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/BUILD create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/LICENSE create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/batch_processor.go create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/failure_detector.go create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/interfaces.go create mode 100644 vendor/github.com/p0lyn0mial/failure-detector/simple_policy.go create mode 100644 vendor/github.com/p0lyn0mial/ttl-cache/BUILD create mode 100644 vendor/github.com/p0lyn0mial/ttl-cache/LICENSE create mode 100644 vendor/github.com/p0lyn0mial/ttl-cache/eviction_store.go diff --git a/Godeps/LICENSES b/Godeps/LICENSES index 4cf42cbba6ef8..27018ed553ab0 100644 --- a/Godeps/LICENSES +++ b/Godeps/LICENSES @@ -16290,6 +16290,2052 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ================================================================================ +================================================================================ += vendor/github.com/p0lyn0mial/batch-working-queue licensed under: = + + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. 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Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. + += vendor/github.com/p0lyn0mial/ttl-cache/LICENSE 1ebbd3e34237af26da5dc08a4e440464 +================================================================================ + + ================================================================================ = vendor/github.com/pelletier/go-toml licensed under: = diff --git a/cmd/kube-apiserver/app/BUILD b/cmd/kube-apiserver/app/BUILD index f7b7d4fdea1e9..15439047cc1c7 100644 --- a/cmd/kube-apiserver/app/BUILD +++ b/cmd/kube-apiserver/app/BUILD @@ -79,6 +79,7 @@ go_library( "//staging/src/k8s.io/kube-aggregator/pkg/client/informers/externalversions/apiregistration/v1:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/controllers/autoregister:go_default_library", "//vendor/github.com/go-openapi/spec:go_default_library", + "//vendor/github.com/p0lyn0mial/failure-detector:go_default_library", "//vendor/github.com/spf13/cobra:go_default_library", "//vendor/k8s.io/klog:go_default_library", ], diff --git a/go.mod b/go.mod index 4805c230a0b22..02c2573214b06 100644 --- a/go.mod +++ b/go.mod @@ -97,6 +97,7 @@ require ( github.com/opencontainers/runc v1.0.0-rc10 github.com/opencontainers/runtime-spec v1.0.0 // indirect github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52 + github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 github.com/pkg/errors v0.9.1 github.com/pmezard/go-difflib v1.0.0 github.com/pquerna/ffjson v0.0.0-20180717144149-af8b230fcd20 // indirect @@ -424,6 +425,9 @@ replace ( github.com/opencontainers/runc => github.com/opencontainers/runc v1.0.0-rc10 github.com/opencontainers/runtime-spec => github.com/opencontainers/runtime-spec v1.0.0 github.com/opencontainers/selinux => github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52 + github.com/p0lyn0mial/batch-working-queue => github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a + github.com/p0lyn0mial/failure-detector => github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 + github.com/p0lyn0mial/ttl-cache => github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f github.com/pelletier/go-toml => github.com/pelletier/go-toml v1.2.0 github.com/peterbourgon/diskv => github.com/peterbourgon/diskv v2.0.1+incompatible github.com/pkg/errors => github.com/pkg/errors v0.9.1 diff --git a/go.sum b/go.sum index 03f536ad2868a..af36fa05e6b07 100644 --- a/go.sum +++ b/go.sum @@ -410,6 +410,12 @@ github.com/opencontainers/runtime-spec v1.0.0 h1:O6L965K88AilqnxeYPks/75HLpp4IG+ github.com/opencontainers/runtime-spec v1.0.0/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/C5hL+LL3ko9hs6T5lQ0= github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52 h1:B8hYj3NxHmjsC3T+tnlZ1UhInqUgnyF1zlGPmzNg2Qk= github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52/go.mod h1:+BLncwf63G4dgOzykXAxcmnFlUaOlkDdmw/CqsW6pjs= +github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a h1:msrvrQTWCWOjUj2sJZhG8JrNeQ43PQsbVy13OnaGVuc= +github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a/go.mod h1:PTDbndC6P2gYYyqKtegbAWqprBd8/3KeeaWmZdxF8ZY= +github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 h1:x0rzTK1F1NBDFnqXuS690g67/gus8mLOVx3J39QbqKY= +github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0/go.mod h1:BkbqMoib5l6c0rSJoh0ep1W+5ZrMbyFpDSQ/cr2trPk= +github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f h1:plVsxZZZJqXa2pN1g54Mw/PAb3tvhmndXyN1zaU6IoA= +github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f/go.mod h1:HcmP7670Zfkf8tjY2fDLgRN7onbUlR83lPx0oOBa2iM= github.com/pelletier/go-toml v1.2.0 h1:T5zMGML61Wp+FlcbWjRDT7yAxhJNAiPPLOFECq181zc= github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic= github.com/peterbourgon/diskv v2.0.1+incompatible h1:UBdAOUP5p4RWqPBg048CAvpKN+vxiaj6gdUUzhl4XmI= diff --git a/staging/src/k8s.io/apiserver/pkg/util/proxy/BUILD b/staging/src/k8s.io/apiserver/pkg/util/proxy/BUILD index 796636062715d..39c0c8ef46c3c 100644 --- a/staging/src/k8s.io/apiserver/pkg/util/proxy/BUILD +++ b/staging/src/k8s.io/apiserver/pkg/util/proxy/BUILD @@ -14,6 +14,7 @@ go_test( "//staging/src/k8s.io/api/core/v1:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library", "//staging/src/k8s.io/client-go/listers/core/v1:go_default_library", "//staging/src/k8s.io/client-go/tools/cache:go_default_library", ], @@ -27,6 +28,7 @@ go_library( deps = [ "//staging/src/k8s.io/api/core/v1:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/api/errors:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library", "//staging/src/k8s.io/client-go/listers/core/v1:go_default_library", ], ) diff --git a/staging/src/k8s.io/kube-aggregator/go.mod b/staging/src/k8s.io/kube-aggregator/go.mod index bf1191a8374c0..da1251c3bbd07 100644 --- a/staging/src/k8s.io/kube-aggregator/go.mod +++ b/staging/src/k8s.io/kube-aggregator/go.mod @@ -10,6 +10,9 @@ require ( github.com/go-openapi/spec v0.19.3 github.com/gogo/protobuf v1.3.1 github.com/json-iterator/go v1.1.8 + github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a // indirect + github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 + github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f // indirect github.com/spf13/cobra v0.0.5 github.com/spf13/pflag v1.0.5 github.com/stretchr/testify v1.4.0 diff --git a/staging/src/k8s.io/kube-aggregator/go.sum b/staging/src/k8s.io/kube-aggregator/go.sum index b3e2acd84361e..5d34682a0c935 100644 --- a/staging/src/k8s.io/kube-aggregator/go.sum +++ b/staging/src/k8s.io/kube-aggregator/go.sum @@ -202,6 +202,12 @@ github.com/onsi/ginkgo v1.11.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+ github.com/onsi/gomega v0.0.0-20170829124025-dcabb60a477c/go.mod h1:C1qb7wdrVGGVU+Z6iS04AVkA3Q65CEZX59MT0QO5uiA= github.com/onsi/gomega v1.7.0 h1:XPnZz8VVBHjVsy1vzJmRwIcSwiUO+JFfrv/xGiigmME= github.com/onsi/gomega v1.7.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY= +github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a h1:msrvrQTWCWOjUj2sJZhG8JrNeQ43PQsbVy13OnaGVuc= +github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a/go.mod h1:PTDbndC6P2gYYyqKtegbAWqprBd8/3KeeaWmZdxF8ZY= +github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 h1:x0rzTK1F1NBDFnqXuS690g67/gus8mLOVx3J39QbqKY= +github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0/go.mod h1:BkbqMoib5l6c0rSJoh0ep1W+5ZrMbyFpDSQ/cr2trPk= +github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f h1:plVsxZZZJqXa2pN1g54Mw/PAb3tvhmndXyN1zaU6IoA= +github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f/go.mod h1:HcmP7670Zfkf8tjY2fDLgRN7onbUlR83lPx0oOBa2iM= github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic= github.com/peterbourgon/diskv v2.0.1+incompatible/go.mod h1:uqqh8zWWbv1HBMNONnaR/tNboyR3/BZd58JJSHlUSCU= github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0= diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/BUILD b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/BUILD index ea1dd7a5481d2..152b7d3c5164c 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/BUILD +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/BUILD @@ -9,23 +9,29 @@ load( go_test( name = "go_default_test", srcs = [ + "dynamic_service_resolver_test.go", "handler_apis_test.go", "handler_proxy_test.go", + "retry_detector_test.go", ], embed = [":go_default_library"], deps = [ + "//staging/src/k8s.io/api/core/v1:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/api/equality:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/util/diff:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/util/proxy:go_default_library", "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library", "//staging/src/k8s.io/apiserver/pkg/authentication/user:go_default_library", "//staging/src/k8s.io/apiserver/pkg/endpoints/request:go_default_library", + "//staging/src/k8s.io/client-go/listers/core/v1:go_default_library", "//staging/src/k8s.io/client-go/tools/cache:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/apis/apiregistration/v1:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/apiserver/scheme:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/client/listers/apiregistration/v1:go_default_library", + "//vendor/github.com/p0lyn0mial/failure-detector:go_default_library", "//vendor/golang.org/x/net/websocket:go_default_library", "//vendor/k8s.io/utils/pointer:go_default_library", ], @@ -36,9 +42,11 @@ go_library( srcs = [ "apiserver.go", "apiservice_controller.go", + "dynamic_service_resolver.go", "handler_apis.go", "handler_proxy.go", "resolvers.go", + "retry_detector.go", ], importmap = "k8s.io/kubernetes/vendor/k8s.io/kube-aggregator/pkg/apiserver", importpath = "k8s.io/kube-aggregator/pkg/apiserver", @@ -85,6 +93,7 @@ go_library( "//staging/src/k8s.io/kube-aggregator/pkg/controllers/openapi/aggregator:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/controllers/status:go_default_library", "//staging/src/k8s.io/kube-aggregator/pkg/registry/apiservice/rest:go_default_library", + "//vendor/github.com/p0lyn0mial/failure-detector:go_default_library", "//vendor/k8s.io/klog:go_default_library", "//vendor/k8s.io/kube-openapi/pkg/common:go_default_library", ], diff --git a/vendor/BUILD b/vendor/BUILD index af41f226d9db6..a7040d9c8b0ea 100644 --- a/vendor/BUILD +++ b/vendor/BUILD @@ -264,6 +264,9 @@ filegroup( "//vendor/github.com/opencontainers/runc/types:all-srcs", "//vendor/github.com/opencontainers/runtime-spec/specs-go:all-srcs", "//vendor/github.com/opencontainers/selinux/go-selinux:all-srcs", + "//vendor/github.com/p0lyn0mial/batch-working-queue:all-srcs", + "//vendor/github.com/p0lyn0mial/failure-detector:all-srcs", + "//vendor/github.com/p0lyn0mial/ttl-cache:all-srcs", "//vendor/github.com/pelletier/go-toml:all-srcs", "//vendor/github.com/peterbourgon/diskv:all-srcs", "//vendor/github.com/pkg/errors:all-srcs", diff --git a/vendor/github.com/p0lyn0mial/batch-working-queue/BUILD b/vendor/github.com/p0lyn0mial/batch-working-queue/BUILD new file mode 100644 index 0000000000000..8a0f0d6823e9a --- /dev/null +++ b/vendor/github.com/p0lyn0mial/batch-working-queue/BUILD @@ -0,0 +1,24 @@ +load("@io_bazel_rules_go//go:def.bzl", "go_library") + +go_library( + name = "go_default_library", + srcs = ["batch_working_queue.go"], + importmap = "k8s.io/kubernetes/vendor/github.com/p0lyn0mial/batch-working-queue", + importpath = "github.com/p0lyn0mial/batch-working-queue", + visibility = ["//visibility:public"], + deps = ["//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library"], +) + +filegroup( + name = "package-srcs", + srcs = glob(["**"]), + tags = ["automanaged"], + visibility = ["//visibility:private"], +) + +filegroup( + name = "all-srcs", + srcs = [":package-srcs"], + tags = ["automanaged"], + visibility = ["//visibility:public"], +) diff --git a/vendor/github.com/p0lyn0mial/batch-working-queue/LICENSE b/vendor/github.com/p0lyn0mial/batch-working-queue/LICENSE new file mode 100644 index 0000000000000..f288702d2fa16 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/batch-working-queue/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/vendor/github.com/p0lyn0mial/batch-working-queue/batch_working_queue.go b/vendor/github.com/p0lyn0mial/batch-working-queue/batch_working_queue.go new file mode 100644 index 0000000000000..91385c8637d86 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/batch-working-queue/batch_working_queue.go @@ -0,0 +1,73 @@ +package batch_working_queue + +import ( + "sync" + + "k8s.io/apimachinery/pkg/util/sets" +) + +type Queue struct { + lock sync.Mutex + + store map[string][]interface{} + dirty map[string][]interface{} + inProgress sets.String + + q []string +} + +func New() *Queue { + return &Queue{ + store: map[string][]interface{}{}, + dirty: map[string][]interface{}{}, + inProgress: sets.NewString(), + } +} + +func (q *Queue) Add(key string, item interface{}) { + q.lock.Lock() + defer q.lock.Unlock() + if q.inProgress.Has(key) { + q.dirty[key] = append(q.dirty[key], item) + return + } + if len(q.store[key]) == 0 { + q.q = append(q.q, key) + } + q.store[key] = append(q.store[key], item) +} + +func (q *Queue) Get() (key string, items []interface{}) { + q.lock.Lock() + defer q.lock.Unlock() + if len(q.q) == 0 { + // TODO: block until we have something in Queue ? + return "", nil + } + workKey := q.q[0] + q.q = q.q[1:] + work := q.store[workKey] + q.store[workKey] = []interface{}{} + q.inProgress.Insert(workKey) + + return workKey, work +} + +func (q *Queue) Done(key string) { + q.lock.Lock() + defer q.lock.Unlock() + + if !q.inProgress.Has(key) { + return + } + if len(q.dirty[key]) == 0 { + q.inProgress.Delete(key) + return + } + + q.store[key] = q.dirty[key] + delete(q.dirty, key) + q.q = append(q.q, key) + q.inProgress.Delete(key) +} + diff --git a/vendor/github.com/p0lyn0mial/failure-detector/BUILD b/vendor/github.com/p0lyn0mial/failure-detector/BUILD new file mode 100644 index 0000000000000..70c2b209da4ba --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/BUILD @@ -0,0 +1,36 @@ +load("@io_bazel_rules_go//go:def.bzl", "go_library") + +go_library( + name = "go_default_library", + srcs = [ + "batch_processor.go", + "failure_detector.go", + "interfaces.go", + "simple_policy.go", + ], + importmap = "k8s.io/kubernetes/vendor/github.com/p0lyn0mial/failure-detector", + importpath = "github.com/p0lyn0mial/failure-detector", + visibility = ["//visibility:public"], + deps = [ + "//staging/src/k8s.io/apimachinery/pkg/util/clock:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/runtime:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library", + "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library", + "//vendor/github.com/p0lyn0mial/batch-working-queue:go_default_library", + "//vendor/github.com/p0lyn0mial/ttl-cache:go_default_library", + ], +) + +filegroup( + name = "package-srcs", + srcs = glob(["**"]), + tags = ["automanaged"], + visibility = ["//visibility:private"], +) + +filegroup( + name = "all-srcs", + srcs = [":package-srcs"], + tags = ["automanaged"], + visibility = ["//visibility:public"], +) diff --git a/vendor/github.com/p0lyn0mial/failure-detector/LICENSE b/vendor/github.com/p0lyn0mial/failure-detector/LICENSE new file mode 100644 index 0000000000000..f288702d2fa16 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/vendor/github.com/p0lyn0mial/failure-detector/batch_processor.go b/vendor/github.com/p0lyn0mial/failure-detector/batch_processor.go new file mode 100644 index 0000000000000..a637e971c26bf --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/batch_processor.go @@ -0,0 +1,77 @@ +package failure_detector + +import ( + "context" + "time" + + utilruntime "k8s.io/apimachinery/pkg/util/runtime" + "k8s.io/apimachinery/pkg/util/wait" +) + +// processFunc a function that processes a batch of EndpointSamples +type processFunc func(objs []*EndpointSample) + +// processor retrieves EndpointSamples from the exposed channel and calls out to processFunc for processing +type processor struct { + batchKeyFn KeyFunc + queue endPointSampleBatchQueue + processFn processFunc + collectCh chan *EndpointSample +} + +// newProcessor creates a processor that adds EndpointSamples to the given queue under a key derived from the given batchKeyFn function and calls out to the given processFn function for processing +func newProcessor(batchKeyFn KeyFunc, processFn processFunc, queue endPointSampleBatchQueue) *processor { + return &processor{ + batchKeyFn: batchKeyFn, + queue: queue, + processFn: processFn, + collectCh: make(chan *EndpointSample, 1000), + } +} + +// run starts the processor that +// - runs one worker for collecting EndpointSamples from the exposed channel and adding them to the queue +// - runs the given number of workers that takes the collected data off the queue and calls out to the defined processFunc +func (p *processor) run(ctx context.Context, workers int) { + // TODO: shutdown the queue + // defer p.queue.Shutdown() + + for i := 0; i < workers; i++ { + go wait.Until(p.worker, time.Second, ctx.Done()) + } + + go wait.Until(p.collector(ctx), time.Second, ctx.Done()) + + <-ctx.Done() +} + +func (p *processor) worker() { + defer utilruntime.HandleCrash() + for p.processNextWorkItem() { + } +} + +func (p *processor) processNextWorkItem() bool { + key, items := p.queue.Get() + defer p.queue.Done(key) + + // sync + p.processFn(items) + + return true +} + +// collector adds collected EndpointSamples to the internal queue for processing +func (p *processor) collector(ctx context.Context) func() { + return func() { + defer utilruntime.HandleCrash() + for { + select { + case <-ctx.Done(): + return + case endpointSample := <-p.collectCh: + p.queue.Add(p.batchKeyFn(endpointSample), endpointSample) + } + } + } +} diff --git a/vendor/github.com/p0lyn0mial/failure-detector/failure_detector.go b/vendor/github.com/p0lyn0mial/failure-detector/failure_detector.go new file mode 100644 index 0000000000000..264efe0211b19 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/failure_detector.go @@ -0,0 +1,169 @@ +package failure_detector + +import ( + "context" + "net/url" + "sync/atomic" + "time" + + batchqueue "github.com/p0lyn0mial/batch-working-queue" + ttlstore "github.com/p0lyn0mial/ttl-cache" + + "k8s.io/apimachinery/pkg/util/clock" + "k8s.io/apimachinery/pkg/util/sets" +) + +// failureDetector is receiving endpoint samples and maintains endpoint status according to logic implemented by a policy evaluator +type failureDetector struct { + // endpointSampleKeyFn maps collected sample (EndpointSample) for a Service to the internal store + endpointSampleKeyFn KeyFunc + + //processor retrieves EndpointSamples from the exposed channel and calls out to processBatch() function for processing + processor *processor + + // store holds WeightedEndpointStatusStore (samples) per Service (Namespace/Service) + store map[string]WeightedEndpointStatusStore + + // readOnlyStore holds a copy of the store that is safe for concurrent (read) access + readOnlyStore atomic.Value + + // createStoreFn a helper function for creating the WeightedEndpointStatusStore store + createStoreFn NewStoreFunc + + // policyEvaluatorFn an external policy function for assessing the endpoints + policyEvaluatorFn EvaluateFunc +} + +func NewDefaultFailureDetector() *failureDetector { + createNewStoreFn := func(ttl time.Duration) WeightedEndpointStatusStore { + return newEndpointStore(ttlstore.New(ttl, clock.RealClock{})) + } + queue := newEndPointSampleBatchQueue(batchqueue.New()) + return newFailureDetector(EndpointSampleToServiceKeyFunction, SimpleWeightedEndpointStatusEvaluator, createNewStoreFn, queue) +} + +func newFailureDetector(endpointSampleKeyKeyFn KeyFunc, policyEvaluator EvaluateFunc, createStoreFn NewStoreFunc, queue endPointSampleBatchQueue) *failureDetector { + fd := &failureDetector{} + processor := newProcessor(endpointSampleKeyKeyFn, fd.processBatch, queue) + fd.processor = processor + fd.store = map[string]WeightedEndpointStatusStore{} + fd.endpointSampleKeyFn = endpointSampleKeyKeyFn + fd.createStoreFn = createStoreFn + fd.policyEvaluatorFn = policyEvaluator + return fd +} + +// processBatch starts processing the retrieved EndPointSamples +// first samples are added to the internal store +// then it calls out to external policy function for assessing +// finally it propagates the changes to external read-only store +func (fd *failureDetector) processBatch(endpointSamples []*EndpointSample) { + if len(endpointSamples) == 0 { + return + } + batchKey := fd.endpointSampleKeyFn(endpointSamples[0]) + endpointsStore := fd.store[batchKey] + if endpointsStore == nil { + endpointsStore = fd.createStoreFn(60 * time.Second) + } + + visitedEndpointsKey := sets.NewString() + for _, endpointSample := range endpointSamples { + endpointKey, sample := convertToKeySample(endpointSample) + endpoint := endpointsStore.Get(endpointKey) + if endpoint == nil { + // the max number of samples we are going to store and process per endpoint is 10 (it could be configurable) + endpoint = newWeightedEndpoint(10, endpointSample.URL) + } + if !visitedEndpointsKey.Has(endpointKey) { + visitedEndpointsKey.Insert(endpointKey) + } + endpoint.Add(sample) + endpointsStore.Add(endpointKeyFunction(endpoint), endpoint) + } + + hasChanged := false + for _, visitedEndpointKey := range visitedEndpointsKey.UnsortedList() { + endpoint := endpointsStore.Get(visitedEndpointKey) + if fd.policyEvaluatorFn(endpoint) { + hasChanged = true + endpointsStore.Add(endpointKeyFunction(endpoint), endpoint) + } + } + + fd.store[batchKey] = endpointsStore + if hasChanged { + fd.propagateChangesToReadOnlyStore() + } +} + +func (fd *failureDetector) Run(ctx context.Context) { + // if you ever change the number of workers then you need to provide a thread-safe store + fd.processor.run(ctx, 1) +} + +// Collector exposes a chan for collecting EndpointSamples +func (fd *failureDetector) Collector() chan<- *EndpointSample { + return fd.processor.collectCh +} + +// EndpointStatus returns the current status of the given endpoint for the given Service +func (fd *failureDetector) EndpointStatus(namespace, service string, url *url.URL) (isHealthy bool, weight float32) { + isHealthy = true + weight = 1.0 + + store := fd.readOnlyStore.Load() + if store == nil { + // nothing has been exported yet + // consider the endpoint healthy + return + } + + serviceStore := store.(map[string]WeightedEndpointStatusStore) + epSample := &EndpointSample{Namespace: namespace, Service:service, URL:url} + + serviceKey := fd.endpointSampleKeyFn(epSample) + endpointsStore := serviceStore[serviceKey] + if endpointsStore == nil { + // we haven't collected any data for this Service + // consider the endpoint healthy + return + } + + endpointKey, _ := convertToKeySample(epSample) + endpoint := endpointsStore.Get(endpointKey) + if endpoint == nil { + // we haven't collected any data for this endpoint + // consider the endpoint healthy + return + } + + weight = endpoint.weight + isHealthy = len(endpoint.status) == 0 + + return +} + +func convertToKeySample(epSample *EndpointSample) (string, *Sample) { + return EndpointSampleKeyFunction(epSample), &Sample{ + err: epSample.Err, + } +} + +// propagateChangesToReadOnlyStore makes a copy of fd.store and puts it into fd.readOnlyStore +func (fd *failureDetector) propagateChangesToReadOnlyStore() { + serviceStoreCopy := map[string]WeightedEndpointStatusStore{} + for serviceKey, epStore := range fd.store { + newEpStore := fd.createStoreFn(24 * 365 * time.Hour) + for _, weightedEndpointStatus := range epStore.List() { + weightedEndpointStatusCopy := newWeightedEndpoint(0, weightedEndpointStatus.url) + weightedEndpointStatusCopy.weight = weightedEndpointStatus.weight + weightedEndpointStatusCopy.status = weightedEndpointStatus.status + newEpStore.Add(endpointKeyFunction(weightedEndpointStatusCopy), weightedEndpointStatusCopy) + + } + serviceStoreCopy[serviceKey] = newEpStore + } + + fd.readOnlyStore.Store(serviceStoreCopy) +} diff --git a/vendor/github.com/p0lyn0mial/failure-detector/interfaces.go b/vendor/github.com/p0lyn0mial/failure-detector/interfaces.go new file mode 100644 index 0000000000000..ffbe68c66b257 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/interfaces.go @@ -0,0 +1,239 @@ +package failure_detector + +import ( + "fmt" + "net/url" + "time" +) + +type KeyFunc func(obj interface{}) string + +// NewStoreFunc a func for creating WeightedEndpointStatus store per Service +type NewStoreFunc func(ttl time.Duration) WeightedEndpointStatusStore + +// EvaluateFunc a function to an external policy evaluator that sets the status and weight of the given endpoint based on the collected samples. +type EvaluateFunc func(endpoint *WeightedEndpointStatus) bool + +// Store an in-memory store for storing and retrieving arbitrary data +// +// For now it is used by newEndpointStore function and converted to a strongly typed store (WeightedEndpointStatus) +// It will be removed in the future once we move the store implementation to this package +type Store interface { + // Add adds the given object to the store under the given key + Add(key string, obj interface{}) + + // Get retrieves an object from the store at the given key + Get(key string) interface{} + + // List returns all objects in the store + List() []interface{} +} + +// WeightedEndpointStatusStore an in-memory store for WeightedEndpointStatus. +// It automatically removed entries that exceed the configured TTL +// as that allows for removing unused/removed endpoints +type WeightedEndpointStatusStore interface { + // Add adds the given object to the store under the given key + Add(key string, obj *WeightedEndpointStatus) + + // Get retrieves WeightedEndpointStatus from the store at the given key + Get(key string) *WeightedEndpointStatus + + // List returns all WeightedEndpointStatus in the store + List() []*WeightedEndpointStatus +} + +// endpointStore implements WeightedEndpointStatusStore interface +type endpointStore struct { + Store +} + +// newEndpointStore creates a new strongly typed store that implements WeightedEndpointStatusStore interface +func newEndpointStore(delegate Store) *endpointStore { + return &endpointStore{Store: delegate} +} + +// Add adds the given WeightedEndpointStatus to the store under the given key +func (e *endpointStore) Add(key string, ep *WeightedEndpointStatus) { + e.Store.Add(key, ep) +} + +// Get retrieves a WeightedEndpointStatus from the store under the given key +func (e *endpointStore) Get(key string) *WeightedEndpointStatus { + rawEndpoint := e.Store.Get(key) + if rawEndpoint == nil { + return nil + } + return rawEndpoint.(*WeightedEndpointStatus) +} + +// List returns all WeightedEndpointStatus in the store +func (e *endpointStore) List() []*WeightedEndpointStatus { + rawEndpoints := e.Store.List() + endpoints := make([]*WeightedEndpointStatus, len(rawEndpoints)) + for idx, rawEndpoint := range rawEndpoints { + endpoints[idx] = rawEndpoint.(*WeightedEndpointStatus) + } + return endpoints +} + +// BatchQueue represents a generic work queue that process items in the order in which they were added, +// it also supports batching - items are grouped by a key and could be retrieved as a package +// +// For now it is used by newEndPointSampleBatchQueue function and converted to a strongly typed queue (endPointSampleBatchQueue) +// It will be removed in the future once we move the queue implementation to this package +type BatchQueue interface { + // Get retrieves the next batch of collected items/work along with the unique key + // A caller must execute the corresponding Done() method once it has finished its work + Get() (key string, items []interface{}) + + // Add adds the given item under the given key to the queue + Add(key string, item interface{}) + + // Done indicates that the caller finished working on items represented by a unique key + // if it has been added again while it was being processed, it will be re-added to the queue for re-processing + Done(key string) +} + +// BatchQueue represents work queue that process EndpointSamples in the order in which they were added, +// it also supports batching - items are grouped by a key and could be retrieved as a package +type endPointSampleBatchQueue interface { + // Get retrieves the next batch of collected EndpointSamples along with the unique key + // A caller must execute the corresponding Done() method once it has finished its work + Get() (key string, items []*EndpointSample) + + // Add adds the given EndpointSample under the given key to the queue + Add(key string, item *EndpointSample) + + // Done indicates that the caller finished working on the batch of EndpointSamples represented by a unique key + // if it has been added again while it was being processed, it will be re-added to the queue for re-processing + Done(key string) +} + +// endpointSampleBatchQueue implements endPointSampleBatchQueue +type endpointSampleBatchQueue struct { + BatchQueue +} + +// Get retrieves the next batch of collected EndpointSamples along with the unique key +// A caller must execute the corresponding Done() method once it has finished its work +func (q *endpointSampleBatchQueue) Get() (key string, items []*EndpointSample) { + key, rawEndpointSample := q.BatchQueue.Get() + endpointSamples := make([]*EndpointSample, len(rawEndpointSample)) + for i, r := range rawEndpointSample { + endpointSamples[i] = r.(*EndpointSample) + } + return key, endpointSamples +} + +// Add adds the given EndpointSample under the given key to the queue +func (q *endpointSampleBatchQueue) Add(key string, item *EndpointSample) { + q.BatchQueue.Add(key, item) +} + +// Done indicates that the caller finished working on the batch of EndpointSamples represented by a unique key +// if it has been added again while it was being processed, it will be re-added to the queue for re-processing +func (q *endpointSampleBatchQueue) Done(key string) { + q.BatchQueue.Done(key) +} + +// newEndPointSampleBatchQueue creates a strongly typed batch queue from the delegate +// the returned queue implements endPointSampleBatchQueue interface +func newEndPointSampleBatchQueue(delegate BatchQueue) endPointSampleBatchQueue { + return &endpointSampleBatchQueue{BatchQueue: delegate} +} + +// EndpointSample represents a sample collected for an endpoint derived from a proxied request. +// it holds: +// - Namespace, Service and URL to uniquely identify the request +// - an optional Err returned from the proxy +type EndpointSample struct { + Namespace string + Service string + URL *url.URL + Err error +} + +// WeightedEndpointStatus represents the current status of the given endpoint based on the collected samples. +// The status will be examined and filled by the external policy. +type WeightedEndpointStatus struct { + data []*Sample + position int + + url *url.URL + status string + weight float32 +} + +// Sample represents a single sample collected for an endpoint +type Sample struct { + err error + // TODO: store latency +} + +// newWeightedEndpoint creates WeightedEndpointStatus for the given URL +// it will store exactly "the size" of Samples +func newWeightedEndpoint(size int, url *url.URL) *WeightedEndpointStatus { + ep := &WeightedEndpointStatus{} + ep.data = make([]*Sample, size, size) + ep.url = url + ep.weight = 1 + return ep +} + +// Add adds the given sample to the internal store +// it will overwrite the old values when it exceeds the configured capacity +func (ep *WeightedEndpointStatus) Add(sample *Sample) { + size := cap(ep.data) + ep.position = ep.position % size + ep.data[ep.position] = sample + ep.position = ep.position + 1 +} + +// Get retrieves the collected samples so far +func (ep *WeightedEndpointStatus) Get() []*Sample { + size := cap(ep.data) + ret := []*Sample{} + + for i := ep.position % size; i < size; i++ { + if ep.data[i] == nil { + break + } + ret = append(ret, ep.data[i]) + } + for i := 0; i < ep.position%size; i++ { + ret = append(ret, ep.data[i]) + } + + return ret +} + +// EndpointSampleToServiceKeyFunction a function used by the batch queue and the internal store (failureDetector.store) for deriving a key from EndpointSample. +// The key identifies a Service an endpoints belongs to +func EndpointSampleToServiceKeyFunction(obj interface{}) string { + item := obj.(*EndpointSample) + return fmt.Sprintf("%s/%s", item.Namespace, item.Service) +} + +// EndpointSampleKeyFunction a function used for deriving a key from an EndpointSample that uniquely identifies it +func EndpointSampleKeyFunction(obj interface{}) string { + item := obj.(*EndpointSample) + if item.URL == nil { + return "" + } + return item.URL.Host +} + +// endpointKeyFunction a function used for deriving a key from a WeightedEndpointStatus that uniquely identifies it +func endpointKeyFunction(obj interface{}) string { + item := obj.(*WeightedEndpointStatus) + if item.url == nil { + return "" + } + return item.url.Host +} + +const ( + // EndpointStatusReasonTooManyErrors means the detector experienced too many samples that indicated an error + EndpointStatusReasonTooManyErrors = "TooManyErrors" +) diff --git a/vendor/github.com/p0lyn0mial/failure-detector/simple_policy.go b/vendor/github.com/p0lyn0mial/failure-detector/simple_policy.go new file mode 100644 index 0000000000000..68c81421c868d --- /dev/null +++ b/vendor/github.com/p0lyn0mial/failure-detector/simple_policy.go @@ -0,0 +1,46 @@ +package failure_detector + +// SimpleWeightedEndpointStatusEvaluator an external policy evaluator that sets the status and weight of the given endpoint based on the collected samples. +// It returns true only if status or wight have changed otherwise false +// +// WeightedEndpointStatus.Status: +// will be set to EndpointStatusReasonTooManyErrors only when it sees 10 errors +// otherwise it will be set to an empty string +// +// WeightedEndpointStatus.Weight: +// will be decreased by 0.1 for each encountered error for example: +// - the value of 1 means no errors +// - the value of 0 means it observed 10 errors +// - the value of 0.7 means it observed 3 errors +func SimpleWeightedEndpointStatusEvaluator(endpoint *WeightedEndpointStatus) bool { + errThreshold := 10 + errCount := 0 + + for _, sample := range endpoint.data { + if sample != nil && sample.err != nil { + errCount++ + } + } + + hasChanged := false + if errCount >= errThreshold && endpoint.status != EndpointStatusReasonTooManyErrors { + endpoint.status = EndpointStatusReasonTooManyErrors + hasChanged = true + } else if endpoint.status != "" { + endpoint.status = "" + hasChanged = true + } + + newWeight := 1 - 0.1*float32(errCount) + prevErrCount := weightToErrorCount(endpoint.weight) + if prevErrCount != errCount { + endpoint.weight = newWeight + hasChanged = true + } + + return hasChanged +} + +func weightToErrorCount(weight float32) int { + return int((1 - weight) * 10) +} diff --git a/vendor/github.com/p0lyn0mial/ttl-cache/BUILD b/vendor/github.com/p0lyn0mial/ttl-cache/BUILD new file mode 100644 index 0000000000000..85ba7aef5a987 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/ttl-cache/BUILD @@ -0,0 +1,24 @@ +load("@io_bazel_rules_go//go:def.bzl", "go_library") + +go_library( + name = "go_default_library", + srcs = ["eviction_store.go"], + importmap = "k8s.io/kubernetes/vendor/github.com/p0lyn0mial/ttl-cache", + importpath = "github.com/p0lyn0mial/ttl-cache", + visibility = ["//visibility:public"], + deps = ["//staging/src/k8s.io/apimachinery/pkg/util/clock:go_default_library"], +) + +filegroup( + name = "package-srcs", + srcs = glob(["**"]), + tags = ["automanaged"], + visibility = ["//visibility:private"], +) + +filegroup( + name = "all-srcs", + srcs = [":package-srcs"], + tags = ["automanaged"], + visibility = ["//visibility:public"], +) diff --git a/vendor/github.com/p0lyn0mial/ttl-cache/LICENSE b/vendor/github.com/p0lyn0mial/ttl-cache/LICENSE new file mode 100644 index 0000000000000..f288702d2fa16 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/ttl-cache/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 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It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/vendor/github.com/p0lyn0mial/ttl-cache/eviction_store.go b/vendor/github.com/p0lyn0mial/ttl-cache/eviction_store.go new file mode 100644 index 0000000000000..127d584bd71e6 --- /dev/null +++ b/vendor/github.com/p0lyn0mial/ttl-cache/eviction_store.go @@ -0,0 +1,85 @@ +package ttl_cache + +import ( + "container/list" + "time" + + "k8s.io/apimachinery/pkg/util/clock" +) + +type item struct { + obj interface{} + timestamp time.Time + key string +} + +type evictionStore struct { + store map[string]*list.Element + queue *list.List + ttl time.Duration + lastEvictionTime time.Time + clock clock.Clock +} + +func New(ttl time.Duration, clock clock.Clock) *evictionStore { + return &evictionStore{ + store: map[string]*list.Element{}, + queue: list.New(), + ttl: ttl, + clock: clock, + } +} + +func (s *evictionStore) Add(key string, obj interface{}) { + ts := s.clock.Now() + defer s.evict(ts) + + if e, ok := s.store[key]; ok { + e.Value.(*item).timestamp = ts + s.queue.MoveToFront(e) + return + } + s.store[key] = s.queue.PushFront(&item{obj: obj, timestamp: ts, key: key}) +} + +func (s *evictionStore) Get(key string) interface{} { + ts := s.clock.Now() + defer s.evict(ts) + + if e, ok := s.store[key]; ok { + e.Value.(*item).timestamp = ts + s.queue.MoveToFront(e) + return e.Value.(*item).obj + } + + return nil +} + +func (s *evictionStore) List() []interface{} { + ret := []interface{}{} + for key, _ := range s.store { + if obj := s.Get(key); obj != nil { + ret = append(ret, obj) + } + } + + return ret +} + +func (s *evictionStore) evict(timestamp time.Time) { + if s.lastEvictionTime.Add(s.ttl).After(timestamp) { + return + } + for { + if s.queue.Len() == 0 { + break + } + e := s.queue.Back() + if e.Value.(*item).timestamp.Add(s.ttl).After(timestamp) { + break + } + delete(s.store, e.Value.(*item).key) + s.queue.Remove(e) + } + s.lastEvictionTime = timestamp +} diff --git a/vendor/modules.txt b/vendor/modules.txt index 8e05e04fa7b47..d45b884ec2814 100644 --- a/vendor/modules.txt +++ b/vendor/modules.txt @@ -617,6 +617,12 @@ github.com/opencontainers/runtime-spec/specs-go # github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52 => github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52 github.com/opencontainers/selinux/go-selinux github.com/opencontainers/selinux/go-selinux/label +# github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a => github.com/p0lyn0mial/batch-working-queue v0.0.0-20200511091501-d87326ed735a +github.com/p0lyn0mial/batch-working-queue +# github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 => github.com/p0lyn0mial/failure-detector v0.0.0-20200511131836-42e70bbc7eb0 +github.com/p0lyn0mial/failure-detector +# github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f => github.com/p0lyn0mial/ttl-cache v0.0.0-20200511091430-b21b42dbc05f +github.com/p0lyn0mial/ttl-cache # github.com/pelletier/go-toml v1.2.0 => github.com/pelletier/go-toml v1.2.0 github.com/pelletier/go-toml # github.com/peterbourgon/diskv v2.0.1+incompatible => github.com/peterbourgon/diskv v2.0.1+incompatible From 7837b867121a0c7bca09f3f02c9c85c18254865c Mon Sep 17 00:00:00 2001 From: Lukasz Szaszkiewicz Date: Tue, 12 May 2020 17:42:53 +0200 Subject: [PATCH 8/8] Proxy.Transport.RoundTrip stops suppressing errors --- .../apimachinery/pkg/util/proxy/transport.go | 2 +- .../pkg/apiserver/retry_detector.go | 20 ++++++++++++++++++- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/staging/src/k8s.io/apimachinery/pkg/util/proxy/transport.go b/staging/src/k8s.io/apimachinery/pkg/util/proxy/transport.go index aecafb3525920..f3ceb2a38fbac 100644 --- a/staging/src/k8s.io/apimachinery/pkg/util/proxy/transport.go +++ b/staging/src/k8s.io/apimachinery/pkg/util/proxy/transport.go @@ -109,7 +109,7 @@ func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) { } resp.Header.Set("Content-Type", "text/plain; charset=utf-8") resp.Header.Set("X-Content-Type-Options", "nosniff") - return resp, nil + return resp, err } if redirect := resp.Header.Get("Location"); redirect != "" { diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go index 82db656c4c284..ce0c386bdda51 100644 --- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go +++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/retry_detector.go @@ -5,6 +5,9 @@ import ( "fmt" "net" "net/http" + "os" + "syscall" + "errors" knet "k8s.io/apimachinery/pkg/util/net" "k8s.io/apimachinery/pkg/util/proxy" @@ -151,6 +154,7 @@ func newHijackResponder(delegate proxy.ErrorResponder, req *http.Request) *hijac func (hr *hijackResponder) Error(w http.ResponseWriter, r *http.Request, err error) { // if we can retry the request do not send a response to the client + hr.lastKnownError = err if !hr.canRetry(err) { hr.delegate.Error(w, r, err) return @@ -172,7 +176,7 @@ func (hr *hijackResponder) LastKnownError() error { } func (hr *hijackResponder) canRetry(err error) bool { - if isHTTPVerbRetriable(hr.req) && (knet.IsConnectionReset(err) || knet.IsConnectionRefused(err)) { + if isHTTPVerbRetriable(hr.req) && (knet.IsConnectionReset(err) || knet.IsConnectionRefused(err) || isExperimental(err)) { return true } return false @@ -180,4 +184,18 @@ func (hr *hijackResponder) canRetry(err error) bool { func isHTTPVerbRetriable(req *http.Request) bool { return req.Method == "GET" +} + +func isExperimental(err error) bool { + var osErr *os.SyscallError + if errors.As(err, &osErr) { + err = osErr.Err + } + + // blocking the network traffic to a node gives: dial tcp 10.129.0.31:8443: connect: no route to host + // no rsp has been sent to the client so it's okay to retry and can pick up a different EP + if errno, ok := err.(syscall.Errno); ok && errno == syscall.EHOSTUNREACH { + return true + } + return false } \ No newline at end of file