Return error when proxy cache get too many request error(429)

  Add 429 too many request error in http error
  Fixes #18707

Signed-off-by: stonezdj <stonezdj@gmail.com>

src/controller/proxy/controller.go

@@ -166,6 +166,9 @@ func (c *controller) UseLocalManifest(ctx context.Context, art lib.ArtifactInfo,
 	remoteRepo := getRemoteRepo(art)
 	exist, desc, err := remote.ManifestExist(remoteRepo, getReference(art)) // HEAD
 	if err != nil {
+		if errors.IsRateLimitError(err) && a != nil { // if rate limit, use local if it exists, otherwise return error
+			return true, nil, nil
+		}
 		return false, nil, err
 	}
 	if !exist || desc == nil {

src/controller/proxy/controller_test.go

@@ -122,6 +122,30 @@ func (p *proxyControllerTestSuite) TestUseLocalManifest_False() {
 	p.Assert().False(result)
 }
 
+func (p *proxyControllerTestSuite) TestUseLocalManifest_429() {
+	ctx := context.Background()
+	dig := "sha256:1a9ec845ee94c202b2d5da74a24f0ed2058318bfa9879fa541efaecba272e86b"
+	desc := &distribution.Descriptor{Digest: digest.Digest(dig)}
+	art := lib.ArtifactInfo{Repository: "library/hello-world", Digest: dig}
+	p.remote.On("ManifestExist", mock.Anything, mock.Anything).Return(false, desc, errors.New("too many requests").WithCode(errors.RateLimitCode))
+	p.local.On("GetManifest", mock.Anything, mock.Anything).Return(nil, nil)
+	_, _, err := p.ctr.UseLocalManifest(ctx, art, p.remote)
+	p.Assert().NotNil(err)
+	errors.IsRateLimitError(err)
+}
+
+func (p *proxyControllerTestSuite) TestUseLocalManifest_429ToLocal() {
+	ctx := context.Background()
+	dig := "sha256:1a9ec845ee94c202b2d5da74a24f0ed2058318bfa9879fa541efaecba272e86b"
+	desc := &distribution.Descriptor{Digest: digest.Digest(dig)}
+	art := lib.ArtifactInfo{Repository: "library/hello-world", Digest: dig}
+	p.remote.On("ManifestExist", mock.Anything, mock.Anything).Return(false, desc, errors.New("too many requests").WithCode(errors.RateLimitCode))
+	p.local.On("GetManifest", mock.Anything, mock.Anything).Return(&artifact.Artifact{}, nil)
+	result, _, err := p.ctr.UseLocalManifest(ctx, art, p.remote)
+	p.Assert().Nil(err)
+	p.Assert().True(result)
+}
+
 func (p *proxyControllerTestSuite) TestUseLocalManifestWithTag_False() {
 	ctx := context.Background()
 	art := lib.ArtifactInfo{Repository: "library/hello-world", Tag: "latest"}

src/lib/errors/const.go

@@ -27,6 +27,8 @@ const (
 	ForbiddenCode = "FORBIDDEN"
 	// MethodNotAllowedCode ...
 	MethodNotAllowedCode = "METHOD_NOT_ALLOWED"
+	// RateLimitCode
+	RateLimitCode = "TOO_MANY_REQUEST"
 	// PreconditionCode ...
 	PreconditionCode = "PRECONDITION"
 	// GeneralCode ...
@@ -105,3 +107,8 @@ func IsConflictErr(err error) bool {
 func IsChallengesUnsupportedErr(err error) bool {
 	return IsErr(err, ChallengesUnsupportedCode)
 }
+
+// IsRateLimitError checks whether the err chains contains rate limit error
+func IsRateLimitError(err error) bool {
+	return IsErr(err, RateLimitCode)
+}

src/lib/http/error.go

@@ -37,6 +37,7 @@ var (
 		errors.MethodNotAllowedCode:            http.StatusMethodNotAllowed,
 		errors.DENIED:                          http.StatusForbidden,
 		errors.NotFoundCode:                    http.StatusNotFound,
+		errors.RateLimitCode:                   http.StatusTooManyRequests,
 		errors.ConflictCode:                    http.StatusConflict,
 		errors.PreconditionCode:                http.StatusPreconditionFailed,
 		errors.ViolateForeignKeyConstraintCode: http.StatusPreconditionFailed,

src/pkg/registry/client.go

@@ -678,6 +678,8 @@ func (c *client) do(req *http.Request) (*http.Response, error) {
 			code = errors.ForbiddenCode
 		case http.StatusNotFound:
 			code = errors.NotFoundCode
+		case http.StatusTooManyRequests:
+			code = errors.RateLimitCode
 		}
 		return nil, errors.New(nil).WithCode(code).
 			WithMessage(message)

src/server/middleware/repoproxy/proxy.go

@@ -46,6 +46,8 @@ const (
 	ensureTagMaxRetry   = 60
 )
 
+var tooManyRequestsError = errors.New("too many requests to upstream registry").WithCode(errors.RateLimitCode)
+
 // BlobGetMiddleware handle get blob request
 func BlobGetMiddleware() func(http.Handler) http.Handler {
 	return middleware.New(func(w http.ResponseWriter, r *http.Request, next http.Handler) {
@@ -112,6 +114,10 @@ func ManifestMiddleware() func(http.Handler) http.Handler {
 				httpLib.SendError(w, err)
 				return
 			}
+			if errors.IsRateLimitError(err) {
+				httpLib.SendError(w, tooManyRequestsError)
+				return
+			}
 			log.Errorf("failed to proxy manifest, fallback to local, request uri: %v, error: %v", r.RequestURI, err)
 			next.ServeHTTP(w, r)
 		}
@@ -202,7 +208,7 @@ func handleManifest(w http.ResponseWriter, r *http.Request, next http.Handler) e
 		err = proxyManifestGet(ctx, w, proxyCtl, p, art, remote)
 	}
 	if err != nil {
-		if errors.IsNotFoundErr(err) {
+		if errors.IsNotFoundErr(err) || errors.IsRateLimitError(err) {
 			return err
 		}
 		log.Warningf("Proxy to remote failed, fallback to local repo, error: %v", err)