1 files changed, 97 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector_test.go b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector_test.go
new file mode 100644
index 000000000..5d3128fae
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector_test.go
@@ -0,0 +1,97 @@
+// Copyright 2014 The Prometheus 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 prometheus_test
+
+import (
+	"expvar"
+	"fmt"
+	"sort"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func ExampleExpvarCollector() {
+	expvarCollector := prometheus.NewExpvarCollector(map[string]*prometheus.Desc{
+		"memstats": prometheus.NewDesc(
+			"expvar_memstats",
+			"All numeric memstats as one metric family. Not a good role-model, actually... ;-)",
+			[]string{"type"}, nil,
+		),
+		"lone-int": prometheus.NewDesc(
+			"expvar_lone_int",
+			"Just an expvar int as an example.",
+			nil, nil,
+		),
+		"http-request-map": prometheus.NewDesc(
+			"expvar_http_request_total",
+			"How many http requests processed, partitioned by status code and http method.",
+			[]string{"code", "method"}, nil,
+		),
+	})
+	prometheus.MustRegister(expvarCollector)
+
+	// The Prometheus part is done here. But to show that this example is
+	// doing anything, we have to manually export something via expvar.  In
+	// real-life use-cases, some library would already have exported via
+	// expvar what we want to re-export as Prometheus metrics.
+	expvar.NewInt("lone-int").Set(42)
+	expvarMap := expvar.NewMap("http-request-map")
+	var (
+		expvarMap1, expvarMap2                             expvar.Map
+		expvarInt11, expvarInt12, expvarInt21, expvarInt22 expvar.Int
+	)
+	expvarMap1.Init()
+	expvarMap2.Init()
+	expvarInt11.Set(3)
+	expvarInt12.Set(13)
+	expvarInt21.Set(11)
+	expvarInt22.Set(212)
+	expvarMap1.Set("POST", &expvarInt11)
+	expvarMap1.Set("GET", &expvarInt12)
+	expvarMap2.Set("POST", &expvarInt21)
+	expvarMap2.Set("GET", &expvarInt22)
+	expvarMap.Set("404", &expvarMap1)
+	expvarMap.Set("200", &expvarMap2)
+	// Results in the following expvar map:
+	// "http-request-count": {"200": {"POST": 11, "GET": 212}, "404": {"POST": 3, "GET": 13}}
+
+	// Let's see what the scrape would yield, but exclude the memstats metrics.
+	metricStrings := []string{}
+	metric := dto.Metric{}
+	metricChan := make(chan prometheus.Metric)
+	go func() {
+		expvarCollector.Collect(metricChan)
+		close(metricChan)
+	}()
+	for m := range metricChan {
+		if strings.Index(m.Desc().String(), "expvar_memstats") == -1 {
+			metric.Reset()
+			m.Write(&metric)
+			metricStrings = append(metricStrings, metric.String())
+		}
+	}
+	sort.Strings(metricStrings)
+	for _, s := range metricStrings {
+		fmt.Println(strings.TrimRight(s, " "))
+	}
+	// Output:
+	// label:<name:"code" value:"200" > label:<name:"method" value:"GET" > untyped:<value:212 >
+	// label:<name:"code" value:"200" > label:<name:"method" value:"POST" > untyped:<value:11 >
+	// label:<name:"code" value:"404" > label:<name:"method" value:"GET" > untyped:<value:13 >
+	// label:<name:"code" value:"404" > label:<name:"method" value:"POST" > untyped:<value:3 >
+	// untyped:<value:42 >
+}