Add unit tests for Contour observer

pkg/metrics/contour_test.go

@@ -0,0 +1,74 @@
+package metrics
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestContourObserver_GetRequestSuccessRate(t *testing.T) {
+	expected := ` sum( rate( envoy_cluster_upstream_rq{ envoy_cluster_name=~"default_podinfo-canary_[0-9a-zA-Z-]+", envoy_response_code!~"5.*" }[1m] ) ) / sum( rate( envoy_cluster_upstream_rq{ envoy_cluster_name=~"default_podinfo-canary_[0-9a-zA-Z-]+", }[1m] ) ) * 100`
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		promql := r.URL.Query()["query"][0]
+		if promql != expected {
+			t.Errorf("\nGot %s \nWanted %s", promql, expected)
+		}
+
+		json := `{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1,"100"]}]}}`
+		w.Write([]byte(json))
+	}))
+	defer ts.Close()
+
+	client, err := NewPrometheusClient(ts.URL, time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	observer := &ContourObserver{
+		client: client,
+	}
+
+	val, err := observer.GetRequestSuccessRate("podinfo", "default", "1m")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	if val != 100 {
+		t.Errorf("Got %v wanted %v", val, 100)
+	}
+}
+
+func TestContourObserver_GetRequestDuration(t *testing.T) {
+	expected := ` histogram_quantile( 0.99, sum( rate( envoy_cluster_upstream_rq_time_bucket{ envoy_cluster_name=~"default_podinfo-canary_[0-9a-zA-Z-]+", }[1m] ) ) by (le) )`
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		promql := r.URL.Query()["query"][0]
+		if promql != expected {
+			t.Errorf("\nGot %s \nWanted %s", promql, expected)
+		}
+
+		json := `{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1,"100"]}]}}`
+		w.Write([]byte(json))
+	}))
+	defer ts.Close()
+
+	client, err := NewPrometheusClient(ts.URL, time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	observer := &ContourObserver{
+		client: client,
+	}
+
+	val, err := observer.GetRequestDuration("podinfo", "default", "1m")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	if val != 100*time.Millisecond {
+		t.Errorf("Got %v wanted %v", val, 100*time.Millisecond)
+	}
+}