kube-metrics-adapter/pkg/provider/hpa_test.go

package provider

import (
	"context"
	"fmt"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
	"github.com/zalando-incubator/kube-metrics-adapter/pkg/collector"
	autoscaling "k8s.io/api/autoscaling/v2"
	"k8s.io/apimachinery/pkg/api/resource"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/client-go/kubernetes/fake"
)

type mockCollectorPlugin struct{}

func (m mockCollectorPlugin) NewCollector(_ context.Context, hpa *autoscaling.HorizontalPodAutoscaler, config *collector.MetricConfig, interval time.Duration) (collector.Collector, error) {
	return mockCollector{}, nil
}

type mockCollector struct{}

func (c mockCollector) GetMetrics(_ context.Context) ([]collector.CollectedMetric, error) {
	return nil, nil
}

func (c mockCollector) Interval() time.Duration {
	return 1 * time.Second
}

type event struct {
	Object    runtime.Object
	EventType string
	Reason    string
	Message   string
}

type mockEventRecorder struct {
	Events []event
}

func (r *mockEventRecorder) Event(object runtime.Object, eventtype, reason, message string) {
	r.Events = append(r.Events, event{
		Object:    object,
		EventType: eventtype,
		Reason:    reason,
		Message:   message,
	})
}

func (r *mockEventRecorder) Eventf(object runtime.Object, eventtype, reason, messageFmt string, args ...interface{}) {
	r.Event(object, eventtype, reason, fmt.Sprintf(messageFmt, args...))
}

func (r *mockEventRecorder) AnnotatedEventf(object runtime.Object, annotations map[string]string, eventtype, reason, messageFmt string, args ...interface{}) {
}

func TestUpdateHPAs(t *testing.T) {
	value := resource.MustParse("1k")

	hpa := &autoscaling.HorizontalPodAutoscaler{
		ObjectMeta: metav1.ObjectMeta{
			Name:      "hpa1",
			Namespace: "default",
			Annotations: map[string]string{
				"metric-config.pods.requests-per-second.json-path/json-key": "$.http_server.rps",
				"metric-config.pods.requests-per-second.json-path/path":     "/metrics",
				"metric-config.pods.requests-per-second.json-path/port":     "9090",
			},
		},
		Spec: autoscaling.HorizontalPodAutoscalerSpec{
			ScaleTargetRef: autoscaling.CrossVersionObjectReference{
				Kind:       "Deployment",
				Name:       "app",
				APIVersion: "apps/v1",
			},
			MinReplicas: &[]int32{1}[0],
			MaxReplicas: 10,
			Metrics: []autoscaling.MetricSpec{
				{
					Type: autoscaling.PodsMetricSourceType,
					Pods: &autoscaling.PodsMetricSource{
						Metric: autoscaling.MetricIdentifier{
							Name: "requests-per-second",
						},
						Target: autoscaling.MetricTarget{
							Type:         autoscaling.AverageValueMetricType,
							AverageValue: &value,
						},
					},
				},
			},
		},
	}

	fakeClient := fake.NewSimpleClientset()

	var err error
	hpa, err = fakeClient.AutoscalingV2().HorizontalPodAutoscalers("default").Create(context.TODO(), hpa, metav1.CreateOptions{})
	require.NoError(t, err)

	collectorFactory := collector.NewCollectorFactory()
	err = collectorFactory.RegisterPodsCollector("", mockCollectorPlugin{})
	require.NoError(t, err)

	provider := NewHPAProvider(fakeClient, 1*time.Second, 1*time.Second, collectorFactory, false, 1*time.Second, 1*time.Second)
	provider.collectorScheduler = NewCollectorScheduler(context.Background(), provider.metricSink)

	err = provider.updateHPAs()
	require.NoError(t, err)
	require.Len(t, provider.collectorScheduler.table, 1)

	// update HPA
	hpa.Annotations["metric-config.pods.requests-per-second.json-path/port"] = "8080"
	_, err = fakeClient.AutoscalingV2().HorizontalPodAutoscalers("default").Update(context.TODO(), hpa, metav1.UpdateOptions{})
	require.NoError(t, err)

	err = provider.updateHPAs()
	require.NoError(t, err)

	require.Len(t, provider.collectorScheduler.table, 1)
}

func TestUpdateHPAsDisregardingIncompatibleHPA(t *testing.T) {
	// Test HPAProvider with disregardIncompatibleHPAs = true

	value := resource.MustParse("1k")

	hpa := &autoscaling.HorizontalPodAutoscaler{
		ObjectMeta: metav1.ObjectMeta{
			Name:        "hpa1",
			Namespace:   "default",
			Annotations: map[string]string{},
		},
		Spec: autoscaling.HorizontalPodAutoscalerSpec{
			ScaleTargetRef: autoscaling.CrossVersionObjectReference{
				Kind:       "Deployment",
				Name:       "app",
				APIVersion: "apps/v1",
			},
			MinReplicas: &[]int32{1}[0],
			MaxReplicas: 10,
			Metrics: []autoscaling.MetricSpec{
				{
					Type: autoscaling.ExternalMetricSourceType,
					External: &autoscaling.ExternalMetricSource{
						Metric: autoscaling.MetricIdentifier{
							Name: "some-other-metric",
						},
						Target: autoscaling.MetricTarget{
							Type:         autoscaling.AverageValueMetricType,
							AverageValue: &value,
						},
					},
				},
			},
		},
	}

	fakeClient := fake.NewSimpleClientset()

	var err error
	_, err = fakeClient.AutoscalingV2().HorizontalPodAutoscalers("default").Create(context.TODO(), hpa, metav1.CreateOptions{})
	require.NoError(t, err)

	collectorFactory := collector.NewCollectorFactory()
	err = collectorFactory.RegisterPodsCollector("", mockCollectorPlugin{})
	require.NoError(t, err)

	eventRecorder := &mockEventRecorder{}
	provider := NewHPAProvider(fakeClient, 1*time.Second, 1*time.Second, collectorFactory, true, 1*time.Second, 1*time.Second)
	provider.recorder = eventRecorder
	provider.collectorScheduler = NewCollectorScheduler(context.Background(), provider.metricSink)

	err = provider.updateHPAs()
	require.NoError(t, err)

	// we don't expect any events if disregardIncompatibleHPAs=true
	require.Len(t, eventRecorder.Events, 0)

	// check for events when disregardIncompatibleHPAs=false
	eventRecorder = &mockEventRecorder{}
	provider = NewHPAProvider(fakeClient, 1*time.Second, 1*time.Second, collectorFactory, false, 1*time.Second, 1*time.Second)
	provider.recorder = eventRecorder
	provider.collectorScheduler = NewCollectorScheduler(context.Background(), provider.metricSink)

	err = provider.updateHPAs()
	require.NoError(t, err)

	// we expect an event when disregardIncompatibleHPAs=false
	require.Len(t, eventRecorder.Events, 1)
}