pkg/metrics/observers: wrap errors

pkg/controller/scheduler.go

@@ -824,7 +824,7 @@ func (c *Controller) runBuiltinMetricChecks(canary *flaggerv1.Canary) bool {
 		if metric.Name == "request-success-rate" {
 			val, err := observer.GetRequestSuccessRate(toMetricModel(canary, metric.Interval))
 			if err != nil {
-				if errors.Is(err, observers.ErrNoValuesFound) {
+				if errors.Is(err, providers.ErrNoValuesFound) {
 					c.recordEventWarningf(canary,
 						"Halt advancement no values found for %s metric %s probably %s.%s is not receiving traffic: %v",
 						metricsProvider, metric.Name, canary.Spec.TargetRef.Name, canary.Namespace, err)
@@ -856,7 +856,7 @@ func (c *Controller) runBuiltinMetricChecks(canary *flaggerv1.Canary) bool {
 		if metric.Name == "request-duration" {
 			val, err := observer.GetRequestDuration(toMetricModel(canary, metric.Interval))
 			if err != nil {
-				if errors.Is(err, observers.ErrNoValuesFound) {
+				if errors.Is(err, providers.ErrNoValuesFound) {
 					c.recordEventWarningf(canary, "Halt advancement no values found for %s metric %s probably %s.%s is not receiving traffic",
 						metricsProvider, metric.Name, canary.Spec.TargetRef.Name, canary.Namespace)
 				} else {
@@ -887,7 +887,7 @@ func (c *Controller) runBuiltinMetricChecks(canary *flaggerv1.Canary) bool {
 		if metric.Query != "" {
 			val, err := observerFactory.Client.RunQuery(metric.Query)
 			if err != nil {
-				if errors.Is(err, observers.ErrNoValuesFound) {
+				if errors.Is(err, providers.ErrNoValuesFound) {
 					c.recordEventWarningf(canary, "Halt advancement no values found for metric: %s",
 						metric.Name)
 				} else {

pkg/metrics/observers/appmesh.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -49,12 +50,12 @@ type AppMeshObserver struct {
 func (ob *AppMeshObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(appMeshQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -63,12 +64,12 @@ func (ob *AppMeshObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateM
 func (ob *AppMeshObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(appMeshQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/contour.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -48,12 +49,12 @@ type ContourObserver struct {
 func (ob *ContourObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(contourQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -62,12 +63,12 @@ func (ob *ContourObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateM
 func (ob *ContourObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(contourQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/crossover.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -63,12 +64,12 @@ func (ob *CrossoverObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplat
 func (ob *CrossoverObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(crossoverQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/crossover_service.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -49,12 +50,12 @@ type CrossoverServiceObserver struct {
 func (ob *CrossoverServiceObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(crossoverServiceQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -63,12 +64,12 @@ func (ob *CrossoverServiceObserver) GetRequestSuccessRate(model flaggerv1.Metric
 func (ob *CrossoverServiceObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(crossoverServiceQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/errors.go

@@ -1,7 +0,0 @@
-package observers
-
-import "errors"
-
-var (
-	ErrNoValuesFound = errors.New("no values found")
-)

pkg/metrics/observers/gloo.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -48,12 +49,12 @@ type GlooObserver struct {
 func (ob *GlooObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(glooQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -62,12 +63,12 @@ func (ob *GlooObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateMode
 func (ob *GlooObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(glooQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/http.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -63,12 +64,12 @@ func (ob *HttpObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateMode
 func (ob *HttpObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(httpQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value*1000)) * time.Millisecond

pkg/metrics/observers/istio.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -52,12 +53,12 @@ type IstioObserver struct {
 func (ob *IstioObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(istioQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -66,12 +67,12 @@ func (ob *IstioObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateMod
 func (ob *IstioObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(istioQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value*1000)) * time.Millisecond

pkg/metrics/observers/linkerd.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -52,12 +53,12 @@ type LinkerdObserver struct {
 func (ob *LinkerdObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(linkerdQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -66,12 +67,12 @@ func (ob *LinkerdObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateM
 func (ob *LinkerdObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(linkerdQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/nginx.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"fmt"
 	"time"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -56,12 +57,12 @@ type NginxObserver struct {
 func (ob *NginxObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateModel) (float64, error) {
 	query, err := RenderQuery(nginxQueries["request-success-rate"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	return value, nil
@@ -70,12 +71,12 @@ func (ob *NginxObserver) GetRequestSuccessRate(model flaggerv1.MetricTemplateMod
 func (ob *NginxObserver) GetRequestDuration(model flaggerv1.MetricTemplateModel) (time.Duration, error) {
 	query, err := RenderQuery(nginxQueries["request-duration"], model)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("rendering query failed: %w", err)
 	}
 
 	value, err := ob.client.RunQuery(query)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("running query failed: %w", err)
 	}
 
 	ms := time.Duration(int64(value)) * time.Millisecond

pkg/metrics/observers/nginx_test.go

@@ -1,6 +1,7 @@
 package observers
 
 import (
+	"errors"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -14,38 +15,61 @@ import (
 )
 
 func TestNginxObserver_GetRequestSuccessRate(t *testing.T) {
-	expected := ` sum( rate( nginx_ingress_controller_requests{ namespace="nginx", ingress="podinfo", status!~"5.*" }[1m] ) ) / sum( rate( nginx_ingress_controller_requests{ namespace="nginx", ingress="podinfo" }[1m] ) ) * 100`
+	t.Run("ok", func(t *testing.T) {
+		expected := ` sum( rate( nginx_ingress_controller_requests{ namespace="nginx", ingress="podinfo", status!~"5.*" }[1m] ) ) / sum( rate( nginx_ingress_controller_requests{ namespace="nginx", ingress="podinfo" }[1m] ) ) * 100`
+		ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			promql := r.URL.Query()["query"][0]
+			assert.Equal(t, expected, promql)
 
-	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		promql := r.URL.Query()["query"][0]
-		assert.Equal(t, expected, promql)
+			json := `{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1,"100"]}]}}`
+			w.Write([]byte(json))
+		}))
+		defer ts.Close()
 
-		json := `{"status":"success","data":{"resultType":"vector","result":[{"metric":{},"value":[1,"100"]}]}}`
-		w.Write([]byte(json))
-	}))
-	defer ts.Close()
+		client, err := providers.NewPrometheusProvider(flaggerv1.MetricTemplateProvider{
+			Type:      "prometheus",
+			Address:   ts.URL,
+			SecretRef: nil,
+		}, nil)
+		require.NoError(t, err)
 
-	client, err := providers.NewPrometheusProvider(flaggerv1.MetricTemplateProvider{
-		Type:      "prometheus",
-		Address:   ts.URL,
-		SecretRef: nil,
-	}, nil)
-	require.NoError(t, err)
+		observer := &NginxObserver{
+			client: client,
+		}
 
-	observer := &NginxObserver{
-		client: client,
-	}
+		val, err := observer.GetRequestSuccessRate(flaggerv1.MetricTemplateModel{
+			Name:      "podinfo",
+			Namespace: "nginx",
+			Target:    "podinfo",
+			Ingress:   "podinfo",
+			Interval:  "1m",
+		})
+		require.NoError(t, err)
 
-	val, err := observer.GetRequestSuccessRate(flaggerv1.MetricTemplateModel{
-		Name:      "podinfo",
-		Namespace: "nginx",
-		Target:    "podinfo",
-		Ingress:   "podinfo",
-		Interval:  "1m",
+		assert.Equal(t, float64(100), val)
 	})
-	require.NoError(t, err)
 
-	assert.Equal(t, float64(100), val)
+	t.Run("no values", func(t *testing.T) {
+		ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			json := `{"status":"success","data":{"resultType":"vector","result":[]}}`
+			w.Write([]byte(json))
+		}))
+		defer ts.Close()
+
+		client, err := providers.NewPrometheusProvider(flaggerv1.MetricTemplateProvider{
+			Type:      "prometheus",
+			Address:   ts.URL,
+			SecretRef: nil,
+		}, nil)
+		require.NoError(t, err)
+
+		observer := &NginxObserver{
+			client: client,
+		}
+
+		_, err = observer.GetRequestSuccessRate(flaggerv1.MetricTemplateModel{})
+		require.True(t, errors.Is(err, providers.ErrNoValuesFound))
+	})
 }
 
 func TestNginxObserver_GetRequestDuration(t *testing.T) {

pkg/metrics/observers/render.go

@@ -3,6 +3,7 @@ package observers
 import (
 	"bufio"
 	"bytes"
+	"fmt"
 	"text/template"
 
 	flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1beta1"
@@ -11,19 +12,18 @@ import (
 func RenderQuery(queryTemplate string, model flaggerv1.MetricTemplateModel) (string, error) {
 	t, err := template.New("tmpl").Funcs(model.TemplateFunctions()).Parse(queryTemplate)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("template parsing failed: %w", err)
 	}
 	var data bytes.Buffer
 	b := bufio.NewWriter(&data)
 
 	if err := t.Execute(b, nil); err != nil {
-		return "", err
+		return "", fmt.Errorf("template excution failed: %w", err)
 	}
 
 	err = b.Flush()
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("buffer flush failed: %w", err)
 	}
-
 	return data.String(), nil
 }