Check metrics server availability during canary initialization

pkg/controller/scheduler.go

@@ -14,10 +14,6 @@ import (
 	"github.com/weaveworks/flagger/pkg/router"
 )
 
-const (
-	MetricsProviderServiceSuffix = ":service"
-)
-
 // scheduleCanaries synchronises the canary map with the jobs map,
 // for new canaries new jobs are created and started
 // for the removed canaries the jobs are stopped and deleted
@@ -119,6 +115,14 @@ func (c *Controller) advanceCanary(name string, namespace string) {
 		return
 	}
 
+	// check metric servers' availability
+	if !cd.SkipAnalysis() && (cd.Status.Phase == "" || cd.Status.Phase == flaggerv1.CanaryPhaseInitializing) {
+		if err := c.checkMetricProviderAvailability(cd); err != nil {
+			c.recordEventErrorf(cd, "Error checking metric providers: %v", err)
+			return
+		}
+	}
+
 	// init mesh router
 	meshRouter := c.routerFactory.MeshRouter(provider, labelSelector)
 

pkg/controller/scheduler_daemonset_fixture_test.go

@@ -79,7 +79,7 @@ func newDaemonSetFixture(c *flaggerv1.Canary) daemonSetFixture {
 	rf := router.NewFactory(nil, kubeClient, flaggerClient, "annotationsPrefix", "", logger, flaggerClient)
 
 	// init observer
-	observerFactory, _ := observers.NewFactory("fake")
+	observerFactory, _ := observers.NewFactory(testMetricsServerURL)
 
 	// init canary factory
 	configTracker := &canary.ConfigTracker{
@@ -616,7 +616,7 @@ func newDaemonSetTestService() *corev1.Service {
 func newDaemonSetTestMetricTemplate() *flaggerv1.MetricTemplate {
 	provider := flaggerv1.MetricTemplateProvider{
 		Type:    "prometheus",
-		Address: "fake",
+		Address: testMetricsServerURL,
 		SecretRef: &corev1.LocalObjectReference{
 			Name: "podinfo-secret-env",
 		},

pkg/controller/scheduler_deployment_fixture_test.go

@@ -107,7 +107,7 @@ func newDeploymentFixture(c *flaggerv1.Canary) fixture {
 	rf := router.NewFactory(nil, kubeClient, flaggerClient, "annotationsPrefix", "", logger, flaggerClient)
 
 	// init observer
-	observerFactory, _ := observers.NewFactory("fake")
+	observerFactory, _ := observers.NewFactory(testMetricsServerURL)
 
 	// init canary factory
 	configTracker := &canary.ConfigTracker{
@@ -708,7 +708,7 @@ func newDeploymentTestHPA() *hpav2.HorizontalPodAutoscaler {
 func newDeploymentTestMetricTemplate() *flaggerv1.MetricTemplate {
 	provider := flaggerv1.MetricTemplateProvider{
 		Type:    "prometheus",
-		Address: "fake",
+		Address: testMetricsServerURL,
 		SecretRef: &corev1.LocalObjectReference{
 			Name: "podinfo-secret-env",
 		},

pkg/controller/scheduler_deployment_test.go

@@ -84,11 +84,9 @@ func TestScheduler_DeploymentRollback(t *testing.T) {
 
 	// run metric checks
 	mocks.ctrl.advanceCanary("podinfo", "default")
-	require.NoError(t, err)
 
 	// finalise analysis
 	mocks.ctrl.advanceCanary("podinfo", "default")
-	require.NoError(t, err)
 
 	// check status
 	c, err = mocks.flaggerClient.FlaggerV1beta1().Canaries("default").Get(context.TODO(), "podinfo", metav1.GetOptions{})

pkg/controller/scheduler_metrics.go

@@ -3,6 +3,7 @@ package controller
 import (
 	"context"
 	"errors"
+	"fmt"
 	"strings"
 	"time"
 
@@ -13,6 +14,66 @@ import (
 	"github.com/weaveworks/flagger/pkg/metrics/providers"
 )
 
+const (
+	MetricsProviderServiceSuffix = ":service"
+)
+
+// to be called during canary initialization
+func (c *Controller) checkMetricProviderAvailability(canary *flaggerv1.Canary) error {
+	for _, metric := range canary.GetAnalysis().Metrics {
+		if metric.Name == "request-success-rate" || metric.Name == "request-duration" {
+			observerFactory := c.observerFactory
+			if canary.Spec.MetricsServer != "" {
+				var err error
+				observerFactory, err = observers.NewFactory(canary.Spec.MetricsServer)
+				if err != nil {
+					return fmt.Errorf("error building Prometheus client for %s %v", canary.Spec.MetricsServer, err)
+				}
+			}
+			if ok, err := observerFactory.Client.IsOnline(); !ok || err != nil {
+				return fmt.Errorf("prometheus not avaiable: %v", err)
+			}
+			continue
+		}
+
+		if metric.TemplateRef != nil {
+			namespace := canary.Namespace
+			if metric.TemplateRef.Namespace != "" {
+				namespace = metric.TemplateRef.Namespace
+			}
+
+			template, err := c.flaggerInformers.MetricInformer.Lister().MetricTemplates(namespace).Get(metric.TemplateRef.Name)
+			if err != nil {
+				return fmt.Errorf("metric template %s.%s error: %v", metric.TemplateRef.Name, namespace, err)
+			}
+
+			var credentials map[string][]byte
+			if template.Spec.Provider.SecretRef != nil {
+				secret, err := c.kubeClient.CoreV1().Secrets(namespace).Get(context.TODO(), template.Spec.Provider.SecretRef.Name, metav1.GetOptions{})
+				if err != nil {
+					return fmt.Errorf("metric template %s.%s secret %s error: %v",
+						metric.TemplateRef.Name, namespace, template.Spec.Provider.SecretRef.Name, err)
+				}
+				credentials = secret.Data
+			}
+
+			factory := providers.Factory{}
+			provider, err := factory.Provider(metric.Interval, template.Spec.Provider, credentials)
+			if err != nil {
+				return fmt.Errorf("metric template %s.%s provider %s error: %v",
+					metric.TemplateRef.Name, namespace, template.Spec.Provider.Type, err)
+			}
+
+			if ok, err := provider.IsOnline(); !ok || err != nil {
+				return fmt.Errorf("%v in metric tempalte %s.%s not avaiable: %v", template.Spec.Provider.Type,
+					template.Name, template.Namespace, err)
+			}
+		}
+	}
+	c.recordEventInfof(canary, "all the metrics providers are available!")
+	return nil
+}
+
 func (c *Controller) runBuiltinMetricChecks(canary *flaggerv1.Canary) bool {
 	// override the global provider if one is specified in the canary spec
 	var metricsProvider string

pkg/controller/scheduler_test.go

@@ -0,0 +1,53 @@
+package controller
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
+	clientset "github.com/weaveworks/flagger/pkg/client/clientset/versioned"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+var testMetricsServerURL string
+
+func TestMain(m *testing.M) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Query()["query"][0] == "vector(1)" {
+			// for IsOnline invoked during canary initialization
+			w.Write([]byte(`{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1545905245.458,"1"]}]}}`))
+			return
+		}
+		w.Write([]byte(`{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1545905245.458,"100"]}]}}`))
+	}))
+
+	testMetricsServerURL = ts.URL
+	defer ts.Close()
+	os.Exit(m.Run())
+}
+
+func assertPhase(flaggerClient clientset.Interface, canary string, phase flaggerv1.CanaryPhase) error {
+	c, err := flaggerClient.FlaggerV1beta1().Canaries("default").Get(context.TODO(), canary, metav1.GetOptions{})
+	if err != nil {
+		return err
+	}
+
+	if c.Status.Phase != phase {
+		return fmt.Errorf("got canary state %s wanted %s", c.Status.Phase, phase)
+	}
+
+	return nil
+}
+
+func alwaysReady() bool {
+	return true
+}
+
+func toFloatPtr(val int) *float64 {
+	v := float64(val)
+	return &v
+}

pkg/metrics/providers/prometheus.go

@@ -69,10 +69,6 @@ func NewPrometheusProvider(provider flaggerv1.MetricTemplateProvider, credential
 
 // RunQuery executes the promQL query and returns the the first result as float64
 func (p *PrometheusProvider) RunQuery(query string) (float64, error) {
-	if p.url.String() == "fake" {
-		return 100, nil
-	}
-
 	query = url.QueryEscape(p.trimQuery(query))
 	u, err := url.Parse(fmt.Sprintf("./api/v1/query?query=%s", query))
 	if err != nil {