Code change:
<ins> // +build integration,!no-etcd /* Copyright 2015 Google Inc. 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 integration import ( "bufio" "fmt" "net/http" "net/http/httptest" "testing" "github.com/GoogleCloudPlatform/kubernetes/pkg/api" "github.com/GoogleCloudPlatform/kubernetes/pkg/api/testapi" "github.com/GoogleCloudPlatform/kubernetes/pkg/client" "github.com/GoogleCloudPlatform/kubernetes/pkg/labels" "github.com/golang/glog" "github.com/golang/protobuf/proto" prometheuspb "github.com/prometheus/client_model/go" ) const scrapeRequestHeader = "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=compact-text" func init() { requireEtcd() } func scrapeMetrics(s *httptest.Server) ([]*prometheuspb.MetricFamily, error) { req, err := http.NewRequest("GET", s.URL+"/metrics", nil) if err != nil { return nil, fmt.Errorf("Unable to create http request: %v", err) } // Ask the prometheus exporter for its text protocol buffer format, since it's // much easier to parse than its plain-text format. Don't use the serialized // proto representation since it uses a non-standard varint delimiter between // metric families. req.Header.Add("Accept", scrapeRequestHeader) client := &http.Client{} resp, err := client.Do(req) if err != nil { return nil, fmt.Errorf("Unable to contact metrics endpoint of master: %v", err) } defer resp.Body.Close() if resp.StatusCode != 200 { return nil, fmt.Errorf("Non-200 response trying to scrape metrics from master: %v", resp) } // Each line in the response body should contain all the data for a single metric. var metrics []*prometheuspb.MetricFamily scanner := bufio.NewScanner(resp.Body) for scanner.Scan() { var metric prometheuspb.MetricFamily if err := proto.UnmarshalText(scanner.Text(), &metric); err != nil { return nil, fmt.Errorf("Failed to unmarshal line of metrics response: %v", err) } glog.Infof("Got metric %q", metric.GetName()) metrics = append(metrics, &metric) } return metrics, nil } func checkForExpectedMetrics(t *testing.T, metrics []*prometheuspb.MetricFamily, expectedMetrics []string) { foundMetrics := make(map[string]bool) for _, metric := range metrics { foundMetrics[metric.GetName()] = true } for _, expected := range expectedMetrics { if _, found := foundMetrics[expected]; !found { t.Errorf("Master metrics did not include expected metric %q", expected) } } } func TestMasterProcessMetrics(t *testing.T) { _, s := runAMaster(t) defer s.Close() metrics, err := scrapeMetrics(s) if err != nil { t.Fatal(err) } checkForExpectedMetrics(t, metrics, []string{ "process_start_time_seconds", "process_cpu_seconds_total", "process_goroutines", "process_open_fds", "process_resident_memory_bytes", }) } func TestApiserverMetrics(t *testing.T) { _, s := runAMaster(t) defer s.Close() // Make a request to the apiserver to ensure there's at least one data point // for the metrics we're expecting -- otherwise, they won't be exported. client := client.NewOrDie(&client.Config{Host: s.URL, Version: testapi.Version()}) if _, err := client.Pods(api.NamespaceDefault).List(labels.Everything()); err != nil { t.Fatalf("unexpected error getting pods: %v", err) } metrics, err := scrapeMetrics(s) if err != nil { t.Fatal(err) } checkForExpectedMetrics(t, metrics, []string{ "apiserver_request_count", "apiserver_request_latencies", }) } </ins>

Related discussion:
text: In 0.13.2, the apiserver has automatically exposed metrics about the process, like start time, memory usage, processor usage, etc. This stopped working sometime between then and when 0.14.0 was cut. They're still correctly exported from the kubelet, interestingly enough. An e2e or integration test is also needed to catch this if it happens again.