[e2e] Check errors in kube-state-metrics own metrics

.gitignore

@@ -2,6 +2,10 @@
 documented_metrics
 code_metrics
 
+# E2e tests output
+/log
+*.bak
+
 # Created by https://www.gitignore.io/api/go
 
 ### Go ###

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/jsonnet-bundler/jsonnet-bundler v0.1.1-0.20190930114713-10e24cb86976
 	github.com/pkg/errors v0.8.1
 	github.com/prometheus/client_golang v1.1.0
+	github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4
 	github.com/prometheus/common v0.6.0
 	github.com/prometheus/prometheus v2.5.0+incompatible
 	github.com/robfig/cron/v3 v3.0.0

tests/e2e.sh

@@ -32,8 +32,6 @@ OS=${OS:-linux}
 
 EXCLUDED_RESOURCE_REGEX="verticalpodautoscaler"
 
-mkdir -p ${KUBE_STATE_METRICS_LOG_DIR}
-
 function finish() {
     echo "calling cleanup function"
     # kill kubectl proxy in background
@@ -166,8 +164,11 @@ set -e
 echo "kube-state-metrics is up and running"
 
 echo "start e2e test for kube-state-metrics"
-KSMURL='http://localhost:8001/api/v1/namespaces/kube-system/services/kube-state-metrics:http-metrics/proxy'
-go test -v ./tests/e2e/ --ksmurl=${KSMURL}
+KSM_HTTP_METRICS_URL='http://localhost:8001/api/v1/namespaces/kube-system/services/kube-state-metrics:http-metrics/proxy'
+KSM_TELEMETRY_URL='http://localhost:8001/api/v1/namespaces/kube-system/services/kube-state-metrics:telemetry/proxy'
+go test -v ./tests/e2e/ --ksm-http-metrics-url=${KSM_HTTP_METRICS_URL} --ksm-telemetry-url=${KSM_TELEMETRY_URL}
+
+mkdir -p ${KUBE_STATE_METRICS_LOG_DIR}
 
 # TODO: re-implement the following test cases in Go with the goal of removing this file.
 echo "access kube-state-metrics metrics endpoint"

tests/e2e/README.md

@@ -0,0 +1,12 @@
+To run these tests, you need to provide two CLI flags:
+
+- `--ksm-http-metrics-url`: url to access the kube-state-metrics service
+- `--ksm-telemetry-url`: url to access the kube-state-metrics telemetry endpoint
+
+Example:
+
+```
+go test -v ./tests/e2e \
+   --ksm-http-metrics-url=http://localhost:8080/ \
+   --ksm-telemetry-url=http://localhost:8081/
+```

tests/e2e/framework/framework.go

@@ -0,0 +1,174 @@
+/*
+Copyright 2019 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package framework
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"path"
+	"strings"
+
+	"github.com/pkg/errors"
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/expfmt"
+)
+
+const (
+	epHealthz = "/healthz"
+	epMetrics = "/metrics"
+)
+
+// The Framework stores a pointer to the KSMClient
+type Framework struct {
+	KsmClient *KSMClient
+}
+
+// New returns a new Framework given the kube-state-metrics service URLs.
+// It delegates the url validation errs to NewKSMClient func.
+func New(ksmHTTPMetricsURL, ksmTelemetryURL string) (*Framework, error) {
+	ksmClient, err := NewKSMClient(ksmHTTPMetricsURL, ksmTelemetryURL)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Framework{
+		KsmClient: ksmClient,
+	}, nil
+}
+
+// The KSMClient is the Kubernetes State Metric client.
+type KSMClient struct {
+	httpMetricsEndpoint *url.URL
+	telemetryEndpoint   *url.URL
+	client              *http.Client
+}
+
+// NewKSMClient retrieves a new KSMClient the kube-state-metrics service URLs.
+// In case of error parsing the provided addresses, it returns an error.
+func NewKSMClient(ksmHTTPMetricsAddress, ksmTelemetryAddress string) (*KSMClient, error) {
+	ksmHTTPMetricsURL, err := validateURL(ksmHTTPMetricsAddress)
+	if err != nil {
+		return nil, err
+	}
+	ksmTelemetryURL, err := validateURL(ksmTelemetryAddress)
+	if err != nil {
+		return nil, err
+	}
+
+	return &KSMClient{
+		httpMetricsEndpoint: ksmHTTPMetricsURL,
+		telemetryEndpoint:   ksmTelemetryURL,
+		client:              &http.Client{},
+	}, nil
+}
+
+func validateURL(address string) (*url.URL, error) {
+	u, err := url.Parse(address)
+	if err != nil {
+		return nil, err
+	}
+	u.Path = strings.TrimRight(u.Path, "/")
+	return u, nil
+}
+
+// IsHealthz makes a request to the /healthz endpoint to get the health status.
+func (k *KSMClient) IsHealthz() (bool, error) {
+	p := path.Join(k.httpMetricsEndpoint.Path, epHealthz)
+
+	u := *k.httpMetricsEndpoint
+	u.Path = p
+
+	req, err := http.NewRequest(http.MethodGet, u.String(), nil)
+	if err != nil {
+		return false, err
+	}
+
+	resp, err := k.client.Do(req)
+	if err != nil {
+		return false, err
+	}
+	defer func() {
+		io.Copy(ioutil.Discard, resp.Body)
+		resp.Body.Close()
+	}()
+
+	if resp.StatusCode != http.StatusOK {
+		return false, fmt.Errorf("server returned HTTP status %s", resp.Status)
+	}
+
+	return true, nil
+}
+
+func (k *KSMClient) writeMetrics(endpoint *url.URL, w io.Writer) error {
+	if endpoint == nil {
+		return errors.New("Endpoint is nil")
+	}
+
+	u := *endpoint
+	u.Path = path.Join(endpoint.Path, epMetrics)
+
+	req, err := http.NewRequest(http.MethodGet, u.String(), nil)
+	if err != nil {
+		return err
+	}
+
+	resp, err := k.client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		io.Copy(ioutil.Discard, resp.Body)
+		resp.Body.Close()
+	}()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("server returned HTTP status %s", resp.Status)
+	}
+
+	io.Copy(w, resp.Body)
+
+	return nil
+}
+
+// Metrics makes a request to the /metrics endpoint on the "http-metrics" port,
+// and writes its content to the writer w.
+func (k *KSMClient) Metrics(w io.Writer) error {
+	return k.writeMetrics(k.httpMetricsEndpoint, w)
+}
+
+// TelemetryMetrics makes a request to the /metrics endpoint on the "telemetry" port,
+// and writes its content to the writer w.
+func (k *KSMClient) TelemetryMetrics(w io.Writer) error {
+	return k.writeMetrics(k.telemetryEndpoint, w)
+}
+
+// ParseMetrics uses a prometheus TextParser to parse metrics, given a function
+// that fetches and writes metrics.
+func (f *Framework) ParseMetrics(metrics func(io.Writer) error) (map[string]*dto.MetricFamily, error) {
+	buf := &bytes.Buffer{}
+	err := metrics(buf)
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to get metrics")
+	}
+
+	parser := &expfmt.TextParser{}
+	return parser.TextToMetricFamilies(buf)
+}