Adding a basic test for the metricStore

Signed-off-by: Muhammad Muaaz Saleem <muhammad.muaaz.saleem@zalando.de>

pkg/provider/metrics_store_test.go

@@ -0,0 +1,73 @@
+package provider
+
+import (
+	"github.com/davecgh/go-spew/spew"
+	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
+	"github.com/stretchr/testify/require"
+	"github.com/zalando-incubator/kube-metrics-adapter/pkg/collector"
+	"k8s.io/api/autoscaling/v2beta1"
+	"k8s.io/apimachinery/pkg/api/resource"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/metrics/pkg/apis/custom_metrics"
+	"testing"
+)
+
+func TestMetricStore(t *testing.T) {
+	var metricStoreTests = []struct {
+		insert collector.CollectedMetric
+		list   []provider.CustomMetricInfo
+		byName struct {
+			name types.NamespacedName
+			info provider.CustomMetricInfo
+		}
+	}{
+		{
+			insert: collector.CollectedMetric{
+				Type: v2beta1.MetricSourceType("Object"),
+				Custom: custom_metrics.MetricValue{
+					MetricName: "metric",
+					Value:      *resource.NewQuantity(0, ""),
+					DescribedObject: custom_metrics.ObjectReference{
+						Name:      "metricObject",
+						Namespace: "default",
+					},
+				},
+			},
+			list: []provider.CustomMetricInfo{
+				{
+					GroupResource: schema.GroupResource{},
+					Namespaced:    true,
+					Metric:        "metric",
+				},
+			},
+			byName: struct {
+				name types.NamespacedName
+				info provider.CustomMetricInfo
+			}{
+				name: types.NamespacedName{Name: "metricObject", Namespace: "default"},
+				info: provider.CustomMetricInfo{
+					GroupResource: schema.GroupResource{},
+					Namespaced:    true,
+					Metric:        "metric",
+				},
+			},
+		},
+	}
+
+	metricsStore := NewMetricStore()
+
+	// Insert a metric with value
+	metricsStore.Insert(metricStoreTests[0].insert)
+
+	// List a metric with value
+	metricInfos := metricsStore.ListAllMetrics()
+	require.Equal(t, metricStoreTests[0].list, metricInfos)
+
+	// Get the metric by name
+	metric := metricsStore.GetMetricsByName(metricStoreTests[0].byName.name, metricStoreTests[0].byName.info)
+
+	require.Equal(t, metricStoreTests[0].insert.Custom, *metric)
+	spew.Dump(metric)
+
+}