feat: add registry k8s manifest fallback

internal/hubmodule/docker/hooks.go

@@ -87,6 +87,10 @@ func manifestFallbackPath(ctx *hooks.RequestContext, clean string) (string, bool
 	return "/v2/" + repo + "/" + repo + rest, true
 }
 
+func RegistryK8sManifestFallbackPath(ctx *hooks.RequestContext, clean string) (string, bool) {
+	return manifestFallbackPath(ctx, clean)
+}
+
 func splitDockerRepoPath(path string) (string, string, bool) {
 	if !strings.HasPrefix(path, "/v2/") {
 		return "", "", false

internal/proxy/handler.go

@@ -22,6 +22,7 @@ import (
 
 	"github.com/any-hub/any-hub/internal/cache"
 	"github.com/any-hub/any-hub/internal/hubmodule"
+	dockermodule "github.com/any-hub/any-hub/internal/hubmodule/docker"
 	"github.com/any-hub/any-hub/internal/logging"
 	"github.com/any-hub/any-hub/internal/proxy/hooks"
 	"github.com/any-hub/any-hub/internal/server"
@@ -218,7 +219,7 @@ func (h *Handler) serveCache(
 			}
 
 			if shouldRevalidate {
-				if resp, err := h.revalidateRequest(c, route, resolveUpstreamURL(route, route.UpstreamURL, c, hook), result.Entry.Locator, ""); err == nil {
+				if resp, err := h.revalidateRequest(c, route, effectiveRevalidateURL(route, c, result.Entry, hook), result.Entry.Locator, ""); err == nil {
 					resp.Body.Close()
 				}
 			}
@@ -259,6 +260,17 @@ func (h *Handler) fetchAndStream(
 		h.logResult(route, upstreamURL.String(), requestID, 0, false, started, err)
 		return h.writeError(c, fiber.StatusBadGateway, "upstream_failed")
 	}
+	effectiveUpstreamPath := ""
+	originalStatus := resp.StatusCode
+	originalPath := ""
+	if hook != nil {
+		originalPath = hook.clean
+	}
+	resp, upstreamURL, effectiveUpstreamPath, err = h.retryRegistryK8sManifestFallback(c, route, requestID, resp, upstreamURL, hook, originalStatus, originalPath)
+	if err != nil {
+		h.logResult(route, upstreamURL.String(), requestID, 0, false, started, err)
+		return h.writeError(c, fiber.StatusBadGateway, "upstream_failed")
+	}
 	if hook != nil && hook.hasHooks && hook.def.RewriteResponse != nil {
 		if rewritten, rewriteErr := applyHookRewrite(hook, resp, requestPath(c)); rewriteErr == nil {
 			resp = rewritten
@@ -273,7 +285,7 @@ func (h *Handler) fetchAndStream(
 
 	shouldStore := policy.allowStore && writer.Enabled() && isCacheableStatus(resp.StatusCode) &&
 		c.Method() == http.MethodGet
-	return h.consumeUpstream(c, route, locator, resp, shouldStore, writer, requestID, started, ctx)
+	return h.consumeUpstream(c, route, locator, resp, shouldStore, writer, requestID, started, ctx, effectiveUpstreamPath)
 }
 
 func applyHookRewrite(hook *hookState, resp *http.Response, path string) (*http.Response, error) {
@@ -325,13 +337,14 @@ func (h *Handler) consumeUpstream(
 	requestID string,
 	started time.Time,
 	ctx context.Context,
+	effectiveUpstreamPath string,
 ) error {
 	upstreamURL := resp.Request.URL.String()
 	method := c.Method()
 	authFailure := isAuthFailure(resp.StatusCode) && route.Config.HasCredentials()
 
 	if shouldStore {
-		return h.cacheAndStream(c, route, locator, resp, writer, requestID, started, ctx, upstreamURL)
+		return h.cacheAndStream(c, route, locator, resp, writer, requestID, started, ctx, upstreamURL, effectiveUpstreamPath)
 	}
 
 	copyResponseHeaders(c, resp.Header)
@@ -369,6 +382,7 @@ func (h *Handler) cacheAndStream(
 	started time.Time,
 	ctx context.Context,
 	upstreamURL string,
+	effectiveUpstreamPath string,
 ) error {
 	copyResponseHeaders(c, resp.Header)
 	c.Set("X-Any-Hub-Upstream", upstreamURL)
@@ -381,7 +395,7 @@ func (h *Handler) cacheAndStream(
 	// 使用 TeeReader 边向客户端回写边落盘，避免大文件在内存中完整缓冲。
 	reader := io.TeeReader(resp.Body, c.Response().BodyWriter())
 
-	opts := cache.PutOptions{ModTime: extractModTime(resp.Header)}
+	opts := cache.PutOptions{ModTime: extractModTime(resp.Header), EffectiveUpstreamPath: effectiveUpstreamPath}
 	entry, err := writer.Put(ctx, locator, reader, opts)
 	h.logResult(route, upstreamURL, requestID, resp.StatusCode, false, started, err)
 	if err != nil {
@@ -774,7 +788,7 @@ func (h *Handler) isCacheFresh(
 		ctx = context.Background()
 	}
 
-	upstreamURL := resolveUpstreamURL(route, route.UpstreamURL, c, hook)
+	upstreamURL := effectiveRevalidateURL(route, c, entry, hook)
 	resp, err := h.revalidateRequest(c, route, upstreamURL, locator, "")
 	if err != nil {
 		return false, err
@@ -825,6 +839,77 @@ func (h *Handler) isCacheFresh(
 	}
 }
 
+func effectiveRevalidateURL(route *server.HubRoute, c fiber.Ctx, entry cache.Entry, hook *hookState) *url.URL {
+	if route == nil || route.UpstreamURL == nil || entry.EffectiveUpstreamPath == "" {
+		return resolveUpstreamURL(route, route.UpstreamURL, c, hook)
+	}
+	clone := *route.UpstreamURL
+	clone.Path = entry.EffectiveUpstreamPath
+	clone.RawPath = entry.EffectiveUpstreamPath
+	return &clone
+}
+
+func (h *Handler) retryRegistryK8sManifestFallback(
+	c fiber.Ctx,
+	route *server.HubRoute,
+	requestID string,
+	resp *http.Response,
+	upstreamURL *url.URL,
+	hook *hookState,
+	originalStatus int,
+	originalPath string,
+) (*http.Response, *url.URL, string, error) {
+	if resp == nil || resp.StatusCode != http.StatusNotFound || hook == nil || hook.ctx == nil {
+		return resp, upstreamURL, "", nil
+	}
+	fallbackPath, ok := dockermodule.RegistryK8sManifestFallbackPath(hook.ctx, hook.clean)
+	if !ok {
+		return resp, upstreamURL, "", nil
+	}
+	resp.Body.Close()
+	fallbackHook := *hook
+	fallbackHook.clean = fallbackPath
+	fallbackResp, fallbackURL, err := h.executeRequest(c, route, &fallbackHook)
+	if err != nil {
+		return nil, upstreamURL, "", err
+	}
+	fallbackResp, fallbackURL, err = h.retryOnAuthFailure(c, route, requestID, time.Now(), fallbackResp, fallbackURL, &fallbackHook)
+	if err != nil {
+		return nil, upstreamURL, "", err
+	}
+	h.logRegistryK8sFallback(route, requestID, originalPath, fallbackPath, originalStatus, c.Method())
+	if fallbackResp.StatusCode == http.StatusOK {
+		return fallbackResp, fallbackURL, fallbackPath, nil
+	}
+	return fallbackResp, fallbackURL, "", nil
+}
+
+func (h *Handler) logRegistryK8sFallback(route *server.HubRoute, requestID string, originalPath string, fallbackPath string, originalStatus int, method string) {
+	if route == nil || h == nil || h.logger == nil {
+		return
+	}
+	fields := logging.RequestFields(
+		route.Config.Name,
+		route.Config.Domain,
+		route.Config.Type,
+		route.Config.AuthMode(),
+		route.Module.Key,
+		false,
+	)
+	fields["action"] = "proxy_fallback"
+	if route.UpstreamURL != nil {
+		fields["upstream_host"] = route.UpstreamURL.Hostname()
+	}
+	fields["original_path"] = originalPath
+	fields["fallback_path"] = fallbackPath
+	fields["original_status"] = originalStatus
+	fields["method"] = method
+	if requestID != "" {
+		fields["request_id"] = requestID
+	}
+	h.logger.WithFields(fields).Info("proxy_registry_k8s_fallback")
+}
+
 func (h *Handler) revalidateRequest(
 	c fiber.Ctx,
 	route *server.HubRoute,

internal/proxy/handler_test.go

@@ -0,0 +1,55 @@
+package proxy
+
+import (
+	"bytes"
+	"net/url"
+	"strings"
+	"testing"
+
+	"github.com/sirupsen/logrus"
+
+	"github.com/any-hub/any-hub/internal/config"
+	"github.com/any-hub/any-hub/internal/hubmodule"
+	"github.com/any-hub/any-hub/internal/server"
+)
+
+func TestRegistryK8sManifestFallbackLogsStructuredEvent(t *testing.T) {
+	buf := new(bytes.Buffer)
+	logger := logrus.New()
+	logger.SetOutput(buf)
+	logger.SetFormatter(&logrus.JSONFormatter{})
+
+	upstreamURL, err := url.Parse("http://registry.k8s.io")
+	if err != nil {
+		t.Fatalf("parse upstream url: %v", err)
+	}
+
+	h := NewHandler(nil, logger, nil)
+	route := &server.HubRoute{
+		Config: config.HubConfig{
+			Name:   "docker",
+			Domain: "k8s.hub.local",
+			Type:   "docker",
+		},
+		Module:      hubmodule.ModuleMetadata{Key: "docker"},
+		UpstreamURL: upstreamURL,
+	}
+
+	h.logRegistryK8sFallback(route, "req-1", "/v2/coredns/manifests/v1.13.1", "/v2/coredns/coredns/manifests/v1.13.1", 404, "GET")
+
+	output := buf.String()
+	for _, want := range []string{
+		"proxy_registry_k8s_fallback",
+		`"hub":"docker"`,
+		`"domain":"k8s.hub.local"`,
+		`"upstream_host":"registry.k8s.io"`,
+		`"original_path":"/v2/coredns/manifests/v1.13.1"`,
+		`"fallback_path":"/v2/coredns/coredns/manifests/v1.13.1"`,
+		`"original_status":404`,
+		`"method":"GET"`,
+	} {
+		if !strings.Contains(output, want) {
+			t.Fatalf("expected log output to contain %s, got %s", want, output)
+		}
+	}
+}

tests/integration/cache_flow_test.go

@@ -26,6 +26,8 @@ import (
 const (
 	dockerManifestPath            = "/v2/library/cache-flow/manifests/latest"
 	dockerManifestNoNamespacePath = "/v2/cache-flow/manifests/latest"
+	registryK8sOriginalManifest   = "/v2/coredns/manifests/v1.13.1"
+	registryK8sFallbackManifest   = "/v2/coredns/coredns/manifests/v1.13.1"
 )
 
 func TestCacheFlowWithConditionalRequest(t *testing.T) {
@@ -286,6 +288,140 @@ func TestDockerNonDockerHubUpstreamKeepsOriginalPath(t *testing.T) {
 	}
 }
 
+func TestRegistryK8sManifestFallbackRetry(t *testing.T) {
+	stub := newRegistryK8sStub(t)
+	stub.setResponse(registryK8sFallbackManifest, http.StatusOK, []byte("fallback manifest"))
+	defer stub.Close()
+
+	app := newDockerProxyTestApp(t, t.TempDir(), "k8s.hub.local", "http://registry.k8s.io", stub.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "http://k8s.hub.local"+registryK8sOriginalManifest, nil)
+	req.Host = "k8s.hub.local"
+	resp, err := app.Test(req)
+	if err != nil {
+		t.Fatalf("app.Test failed: %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != fiber.StatusOK {
+		body, _ := io.ReadAll(resp.Body)
+		t.Fatalf("expected 200, got %d (body=%s)", resp.StatusCode, string(body))
+	}
+	if stub.pathHits(registryK8sOriginalManifest, http.MethodGet) != 1 {
+		t.Fatalf("expected single original manifest hit")
+	}
+	if stub.pathHits(registryK8sFallbackManifest, http.MethodGet) != 1 {
+		t.Fatalf("expected single fallback manifest hit")
+	}
+}
+
+func TestRegistryK8sManifestFallbackNotAttemptedWhenOriginalSucceeds(t *testing.T) {
+	stub := newRegistryK8sStub(t)
+	stub.setResponse(registryK8sOriginalManifest, http.StatusOK, []byte("original manifest"))
+	defer stub.Close()
+
+	app := newDockerProxyTestApp(t, t.TempDir(), "k8s.hub.local", "http://registry.k8s.io", stub.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "http://k8s.hub.local"+registryK8sOriginalManifest, nil)
+	req.Host = "k8s.hub.local"
+	resp, err := app.Test(req)
+	if err != nil {
+		t.Fatalf("app.Test failed: %v", err)
+	}
+	resp.Body.Close()
+
+	if resp.StatusCode != fiber.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	if stub.pathHits(registryK8sFallbackManifest, http.MethodGet) != 0 {
+		t.Fatalf("expected no fallback hit")
+	}
+}
+
+func TestRegistryK8sManifestFallbackNotAttemptedForNonRegistryHost(t *testing.T) {
+	stub := newRegistryK8sStub(t)
+	stub.setResponse(registryK8sFallbackManifest, http.StatusOK, []byte("fallback manifest"))
+	defer stub.Close()
+
+	app := newDockerProxyTestApp(t, t.TempDir(), "mirror.hub.local", stub.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "http://mirror.hub.local"+registryK8sOriginalManifest, nil)
+	req.Host = "mirror.hub.local"
+	resp, err := app.Test(req)
+	if err != nil {
+		t.Fatalf("app.Test failed: %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != fiber.StatusNotFound {
+		body, _ := io.ReadAll(resp.Body)
+		t.Fatalf("expected 404, got %d (body=%s)", resp.StatusCode, string(body))
+	}
+	if stub.pathHits(registryK8sFallbackManifest, http.MethodGet) != 0 {
+		t.Fatalf("expected no fallback hit for non-registry host")
+	}
+}
+
+func TestRegistryK8sManifestFallbackSecondRequestHitsCache(t *testing.T) {
+	stub := newRegistryK8sStub(t)
+	stub.setResponse(registryK8sFallbackManifest, http.StatusOK, []byte("fallback manifest"))
+	defer stub.Close()
+
+	app := newDockerProxyTestApp(t, t.TempDir(), "k8s.hub.local", "http://registry.k8s.io", stub.URL)
+
+	makeRequest := func() *http.Response {
+		req := httptest.NewRequest(http.MethodGet, "http://k8s.hub.local"+registryK8sOriginalManifest, nil)
+		req.Host = "k8s.hub.local"
+		resp, err := app.Test(req)
+		if err != nil {
+			t.Fatalf("app.Test failed: %v", err)
+		}
+		return resp
+	}
+
+	resp1 := makeRequest()
+	resp1.Body.Close()
+	resp2 := makeRequest()
+	defer resp2.Body.Close()
+
+	if resp2.Header.Get("X-Any-Hub-Cache-Hit") != "true" {
+		t.Fatalf("expected second request to hit cache")
+	}
+	if stub.pathHits(registryK8sOriginalManifest, http.MethodGet) != 1 {
+		t.Fatalf("expected original 404 path to be requested once, got %d", stub.pathHits(registryK8sOriginalManifest, http.MethodGet))
+	}
+}
+
+func TestRegistryK8sFallbackCacheRevalidatesEffectivePath(t *testing.T) {
+	stub := newRegistryK8sStub(t)
+	stub.setResponse(registryK8sFallbackManifest, http.StatusOK, []byte("fallback manifest"))
+	defer stub.Close()
+
+	app := newDockerProxyTestApp(t, t.TempDir(), "k8s.hub.local", "http://registry.k8s.io", stub.URL)
+
+	makeRequest := func() *http.Response {
+		req := httptest.NewRequest(http.MethodGet, "http://k8s.hub.local"+registryK8sOriginalManifest, nil)
+		req.Host = "k8s.hub.local"
+		resp, err := app.Test(req)
+		if err != nil {
+			t.Fatalf("app.Test failed: %v", err)
+		}
+		return resp
+	}
+
+	resp1 := makeRequest()
+	resp1.Body.Close()
+	resp2 := makeRequest()
+	resp2.Body.Close()
+
+	if stub.pathHits(registryK8sOriginalManifest, http.MethodHead) != 0 {
+		t.Fatalf("expected no HEAD revalidation against original path, got %d", stub.pathHits(registryK8sOriginalManifest, http.MethodHead))
+	}
+	if stub.pathHits(registryK8sFallbackManifest, http.MethodHead) == 0 {
+		t.Fatalf("expected HEAD revalidation against fallback path")
+	}
+}
+
 type cacheFlowStub struct {
 	server      *http.Server
 	listener    net.Listener
@@ -300,6 +436,22 @@ type cacheFlowStub struct {
 	lastMod     string
 }
 
+type registryK8sStub struct {
+	server   *http.Server
+	listener net.Listener
+	URL      string
+
+	mu        sync.Mutex
+	responses map[string]registryK8sResponse
+	hits      map[string]int
+}
+
+type registryK8sResponse struct {
+	status int
+	body   []byte
+	etag   string
+}
+
 func newCacheFlowStub(t *testing.T, paths ...string) *cacheFlowStub {
 	t.Helper()
 	stub := &cacheFlowStub{
@@ -335,6 +487,32 @@ func newCacheFlowStub(t *testing.T, paths ...string) *cacheFlowStub {
 	return stub
 }
 
+func newRegistryK8sStub(t *testing.T) *registryK8sStub {
+	t.Helper()
+	stub := &registryK8sStub{
+		responses: make(map[string]registryK8sResponse),
+		hits:      make(map[string]int),
+	}
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", stub.handle)
+
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Skipf("unable to start registry.k8s.io stub listener: %v", err)
+	}
+
+	server := &http.Server{Handler: mux}
+	stub.server = server
+	stub.listener = listener
+	stub.URL = "http://" + listener.Addr().String()
+
+	go func() {
+		_ = server.Serve(listener)
+	}()
+
+	return stub
+}
+
 func (s *cacheFlowStub) Close() {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 	defer cancel()
@@ -346,6 +524,109 @@ func (s *cacheFlowStub) Close() {
 	}
 }
 
+func (s *registryK8sStub) Close() {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+	defer cancel()
+	if s.server != nil {
+		_ = s.server.Shutdown(ctx)
+	}
+	if s.listener != nil {
+		_ = s.listener.Close()
+	}
+}
+
+func (s *registryK8sStub) setResponse(path string, status int, body []byte) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.responses[path] = registryK8sResponse{
+		status: status,
+		body:   append([]byte(nil), body...),
+		etag:   fmt.Sprintf(`"%s-etag"`, strings.ReplaceAll(strings.Trim(path, "/"), "/", "-")),
+	}
+}
+
+func (s *registryK8sStub) pathHits(path string, method string) int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.hits[method+" "+path]
+}
+
+func (s *registryK8sStub) handle(w http.ResponseWriter, r *http.Request) {
+	s.mu.Lock()
+	s.hits[r.Method+" "+r.URL.Path]++
+	resp, ok := s.responses[r.URL.Path]
+	s.mu.Unlock()
+
+	if !ok {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusNotFound)
+		_, _ = w.Write([]byte(`{"errors":[{"code":"MANIFEST_UNKNOWN","message":"manifest unknown"}]}`))
+		return
+	}
+	w.Header().Set("Content-Type", "application/vnd.docker.distribution.manifest.v2+json")
+	w.Header().Set("Etag", resp.etag)
+	w.Header().Set("Last-Modified", time.Now().UTC().Format(http.TimeFormat))
+	if r.Method == http.MethodHead {
+		for _, candidate := range r.Header.Values("If-None-Match") {
+			if strings.Trim(candidate, `"`) == strings.Trim(resp.etag, `"`) {
+				w.WriteHeader(http.StatusNotModified)
+				return
+			}
+		}
+		w.WriteHeader(resp.status)
+		return
+	}
+	w.WriteHeader(resp.status)
+	_, _ = w.Write(resp.body)
+}
+
+func newDockerProxyTestApp(t *testing.T, storageDir string, domain string, upstream string, proxyURLs ...string) *fiber.App {
+	t.Helper()
+	proxyURL := ""
+	if len(proxyURLs) > 0 {
+		proxyURL = proxyURLs[0]
+	}
+	cfg := &config.Config{
+		Global: config.GlobalConfig{
+			ListenPort:  5000,
+			CacheTTL:    config.Duration(30 * time.Second),
+			StoragePath: storageDir,
+		},
+		Hubs: []config.HubConfig{
+			{
+				Name:     "docker",
+				Domain:   domain,
+				Type:     "docker",
+				Upstream: upstream,
+				Proxy:    proxyURL,
+			},
+		},
+	}
+
+	registry, err := server.NewHubRegistry(cfg)
+	if err != nil {
+		t.Fatalf("registry error: %v", err)
+	}
+	logger := logrus.New()
+	logger.SetOutput(io.Discard)
+	store, err := cache.NewStore(storageDir)
+	if err != nil {
+		t.Fatalf("store error: %v", err)
+	}
+	client := server.NewUpstreamClient(cfg)
+	handler := proxy.NewHandler(client, logger, store)
+	app, err := server.NewApp(server.AppOptions{
+		Logger:     logger,
+		Registry:   registry,
+		Proxy:      handler,
+		ListenPort: 5000,
+	})
+	if err != nil {
+		t.Fatalf("app error: %v", err)
+	}
+	return app
+}
+
 func (s *cacheFlowStub) handle(w http.ResponseWriter, r *http.Request) {
 	s.mu.Lock()
 	etag := s.etag