clientv3: added example for client metrics

clientv3/example_metrics_test.go

@@ -0,0 +1,46 @@
+// Copyright 2016 The etcd Authors
+//
+// 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 clientv3_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func ExampleMetrics_All() {
+	// listen for all prometheus metrics
+	go func() {
+		http.Handle("/metrics", prometheus.Handler())
+		log.Fatal(http.ListenAndServe(":47989", nil))
+	}()
+
+	url := "http://localhost:47989/metrics"
+
+	// make an http request to fetch all prometheus metrics
+	resp, err := http.Get(url)
+	if err != nil {
+		log.Fatalf("fetch error: %v", err)
+	}
+	b, err := ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		log.Fatalf("fetch error: reading %s: %v", url, err)
+	}
+	fmt.Printf("%s", b)
+}