From b85215ce042fb08b3c000f8d9a0888d0dfde3a1d Mon Sep 17 00:00:00 2001 From: Haibing Zhou Date: Wed, 10 Jan 2024 10:21:08 -0800 Subject: [PATCH] webhook: add options to disable resource_namespace tag in metrics To add some context, historically, `resource_name` was removed from this tag list due to its high potential of causing high metrics cardinality. See [knative/pkg#1464][1] for more information. While that's great, but it might not be sufficient for large scale use cases where namespaces can be super dynamic (with generateName, too) or grows fase enough. There is an issue report from [tektoncd/pipeline#3171][2] which talks about this. This proposal makes it possible to disable `resource_namespace` tag via an option function. The default behavior is not changed, so no user impact if any of existing users rely on this tag. There is no API contract change either due to the beauty of variadic functions. Now downstream projects can consume this by override `StatsReporter` in webhook context options with their own preference. As a caveat here, if downstream project does choose to override `StatsReporter`, the default `ReportMetrics` function shouldn't be called by default as they may now have a different set of tag keys to report. As such, this function is only called if the default `StatsReporter` is used. [1]: https://github.com/knative/pkg/pull/1464 [2]: https://github.com/tektoncd/pipeline/issues/3171 --- injection/sharedmain/main.go | 3 --- webhook/stats_reporter.go | 45 +++++++++++++++++++++++++------- webhook/stats_reporter_test.go | 47 +++++++++++++++++++++++++++++++--- webhook/webhook.go | 1 + 4 files changed, 81 insertions(+), 15 deletions(-) diff --git a/injection/sharedmain/main.go b/injection/sharedmain/main.go index 25562e965e..2703e4b7f4 100644 --- a/injection/sharedmain/main.go +++ b/injection/sharedmain/main.go @@ -289,9 +289,6 @@ func MainWithConfig(ctx context.Context, component string, cfg *rest.Config, cto // and pass them in. var wh *webhook.Webhook if len(webhooks) > 0 { - // Register webhook metrics - webhook.RegisterMetrics() - wh, err = webhook.New(ctx, webhooks) if err != nil { logger.Fatalw("Failed to create webhook", zap.Error(err)) diff --git a/webhook/stats_reporter.go b/webhook/stats_reporter.go index 1fe30e8af1..415eb82dfa 100644 --- a/webhook/stats_reporter.go +++ b/webhook/stats_reporter.go @@ -71,13 +71,26 @@ type StatsReporter interface { ReportConversionRequest(request *apixv1.ConversionRequest, response *apixv1.ConversionResponse, d time.Duration) error } +type options struct { + resourceNamespace bool +} + +type Option func(opts *options) + +func WithoutResourceNamespace() Option { + return func(opts *options) { + opts.resourceNamespace = false + } +} + // reporter implements StatsReporter interface type reporter struct { - ctx context.Context + ctx context.Context + opts options } // NewStatsReporter creates a reporter for webhook metrics -func NewStatsReporter() (StatsReporter, error) { +func NewStatsReporter(opts ...Option) (StatsReporter, error) { ctx, err := tag.New( context.Background(), ) @@ -85,13 +98,17 @@ func NewStatsReporter() (StatsReporter, error) { return nil, err } - return &reporter{ctx: ctx}, nil + options := options{resourceNamespace: true} + for _, opt := range opts { + opt(&options) + } + + return &reporter{ctx: ctx, opts: options}, nil } // Captures req count metric, recording the count and the duration func (r *reporter) ReportAdmissionRequest(req *admissionv1.AdmissionRequest, resp *admissionv1.AdmissionResponse, d time.Duration) error { - ctx, err := tag.New( - r.ctx, + mutators := []tag.Mutator{ tag.Insert(requestOperationKey, string(req.Operation)), tag.Insert(kindGroupKey, req.Kind.Group), tag.Insert(kindVersionKey, req.Kind.Version), @@ -99,9 +116,12 @@ func (r *reporter) ReportAdmissionRequest(req *admissionv1.AdmissionRequest, res tag.Insert(resourceGroupKey, req.Resource.Group), tag.Insert(resourceVersionKey, req.Resource.Version), tag.Insert(resourceResourceKey, req.Resource.Resource), - tag.Insert(resourceNamespaceKey, req.Namespace), tag.Insert(admissionAllowedKey, strconv.FormatBool(resp.Allowed)), - ) + } + if r.opts.resourceNamespace { + mutators = append(mutators, tag.Insert(resourceNamespaceKey, req.Namespace)) + } + ctx, err := tag.New(r.ctx, mutators...) if err != nil { return err } @@ -131,7 +151,7 @@ func (r *reporter) ReportConversionRequest(req *apixv1.ConversionRequest, resp * return nil } -func RegisterMetrics() { +func RegisterMetrics(opts ...Option) { tagKeys := []tag.Key{ requestOperationKey, kindGroupKey, @@ -140,13 +160,20 @@ func RegisterMetrics() { resourceGroupKey, resourceVersionKey, resourceResourceKey, - resourceNamespaceKey, admissionAllowedKey, desiredAPIVersionKey, resultStatusKey, resultReasonKey, resultCodeKey} + options := options{resourceNamespace: true} + for _, opt := range opts { + opt(&options) + } + if options.resourceNamespace { + tagKeys = append(tagKeys, resourceNamespaceKey) + } + if err := view.Register( &view.View{ Description: requestCountM.Description(), diff --git a/webhook/stats_reporter_test.go b/webhook/stats_reporter_test.go index e3911b4d4a..ca997b7689 100644 --- a/webhook/stats_reporter_test.go +++ b/webhook/stats_reporter_test.go @@ -70,6 +70,47 @@ func TestWebhookStatsReporterAdmission(t *testing.T) { metricstest.CheckDistributionData(t, requestLatenciesName, expectedTags, 2, shortTime, longTime) } +func TestWebhookStatsReporterAdmissionWithoutNamespaceTag(t *testing.T) { + setup(WithoutResourceNamespace()) + req := &admissionv1.AdmissionRequest{ + UID: "705ab4f5-6393-11e8-b7cc-42010a800002", + Kind: metav1.GroupVersionKind{Group: "autoscaling", Version: "v1", Kind: "Scale"}, + Resource: metav1.GroupVersionResource{Group: "apps", Version: "v1", Resource: "deployments"}, + Name: "my-deployment", + Namespace: "my-namespace", + Operation: admissionv1.Update, + } + + resp := &admissionv1.AdmissionResponse{ + UID: req.UID, + Allowed: true, + } + + r, _ := NewStatsReporter(WithoutResourceNamespace()) + + shortTime, longTime := 1100.0, 9100.0 + expectedTags := map[string]string{ + requestOperationKey.Name(): string(req.Operation), + kindGroupKey.Name(): req.Kind.Group, + kindVersionKey.Name(): req.Kind.Version, + kindKindKey.Name(): req.Kind.Kind, + resourceGroupKey.Name(): req.Resource.Group, + resourceVersionKey.Name(): req.Resource.Version, + resourceResourceKey.Name(): req.Resource.Resource, + admissionAllowedKey.Name(): strconv.FormatBool(resp.Allowed), + } + + if err := r.ReportAdmissionRequest(req, resp, time.Duration(shortTime)*time.Millisecond); err != nil { + t.Fatalf("ReportAdmissionRequest() = %v", err) + } + if err := r.ReportAdmissionRequest(req, resp, time.Duration(longTime)*time.Millisecond); err != nil { + t.Fatalf("ReportAdmissionRequest() = %v", err) + } + + metricstest.CheckCountData(t, requestCountName, expectedTags, 2) + metricstest.CheckDistributionData(t, requestLatenciesName, expectedTags, 2, shortTime, longTime) +} + func TestWebhookStatsReporterConversion(t *testing.T) { setup() req := &apixv1.ConversionRequest{ @@ -103,12 +144,12 @@ func TestWebhookStatsReporterConversion(t *testing.T) { metricstest.CheckDistributionData(t, requestLatenciesName, expectedTags, 2, shortTime, longTime) } -func setup() { +func setup(opts ...Option) { resetMetrics() } // opencensus metrics carry global state that need to be reset between unit tests -func resetMetrics() { +func resetMetrics(opts ...Option) { metricstest.Unregister(requestCountName, requestLatenciesName) - RegisterMetrics() + RegisterMetrics(opts...) } diff --git a/webhook/webhook.go b/webhook/webhook.go index eff693e80d..adeb104b3c 100644 --- a/webhook/webhook.go +++ b/webhook/webhook.go @@ -144,6 +144,7 @@ func New( logger := logging.FromContext(ctx) if opts.StatsReporter == nil { + RegisterMetrics() reporter, err := NewStatsReporter() if err != nil { return nil, err