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  • Committer: Nicholas Skaggs
  • Date: 2016-08-26 19:28:00 UTC
  • mfrom: (1.5.1)
  • Revision ID: nicholas.skaggs@canonical.com-20160826192800-b2rgj3da7tgfdca4
* New upstream release 2.0-beta16
* Remove all quilt patches
* Ensure autopkgtests run on LXD upload (LP: #1614724)
* Update debian/copyrights

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src/github.com/prometheus/client_golang/prometheus/expvar_test.go
 
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// Copyright 2014 The Prometheus Authors
 
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// Licensed under the Apache License, Version 2.0 (the "License");
 
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// you may not use this file except in compliance with the License.
 
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// You may obtain a copy of the License at
 
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//
 
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// http://www.apache.org/licenses/LICENSE-2.0
 
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//
 
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// Unless required by applicable law or agreed to in writing, software
 
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// distributed under the License is distributed on an "AS IS" BASIS,
 
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 
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// See the License for the specific language governing permissions and
 
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// limitations under the License.
 
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package prometheus_test
 
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import (
 
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        "expvar"
 
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        "fmt"
 
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        "sort"
 
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        "strings"
 
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        dto "github.com/prometheus/client_model/go"
 
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        "github.com/prometheus/client_golang/prometheus"
 
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)
 
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func ExampleExpvarCollector() {
 
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        expvarCollector := prometheus.NewExpvarCollector(map[string]*prometheus.Desc{
 
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                "memstats": prometheus.NewDesc(
 
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                        "expvar_memstats",
 
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                        "All numeric memstats as one metric family. Not a good role-model, actually... ;-)",
 
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                        []string{"type"}, nil,
 
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                ),
 
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                "lone-int": prometheus.NewDesc(
 
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                        "expvar_lone_int",
 
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                        "Just an expvar int as an example.",
 
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                        nil, nil,
 
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                ),
 
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                "http-request-map": prometheus.NewDesc(
 
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                        "expvar_http_request_total",
 
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                        "How many http requests processed, partitioned by status code and http method.",
 
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                        []string{"code", "method"}, nil,
 
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                ),
 
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        })
 
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        prometheus.MustRegister(expvarCollector)
 
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        // The Prometheus part is done here. But to show that this example is
 
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        // doing anything, we have to manually export something via expvar.  In
 
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        // real-life use-cases, some library would already have exported via
 
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        // expvar what we want to re-export as Prometheus metrics.
 
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        expvar.NewInt("lone-int").Set(42)
 
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        expvarMap := expvar.NewMap("http-request-map")
 
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        var (
 
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                expvarMap1, expvarMap2                             expvar.Map
 
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                expvarInt11, expvarInt12, expvarInt21, expvarInt22 expvar.Int
 
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        )
 
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        expvarMap1.Init()
 
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        expvarMap2.Init()
 
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        expvarInt11.Set(3)
 
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        expvarInt12.Set(13)
 
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        expvarInt21.Set(11)
 
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        expvarInt22.Set(212)
 
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        expvarMap1.Set("POST", &expvarInt11)
 
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        expvarMap1.Set("GET", &expvarInt12)
 
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        expvarMap2.Set("POST", &expvarInt21)
 
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        expvarMap2.Set("GET", &expvarInt22)
 
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        expvarMap.Set("404", &expvarMap1)
 
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        expvarMap.Set("200", &expvarMap2)
 
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        // Results in the following expvar map:
 
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        // "http-request-count": {"200": {"POST": 11, "GET": 212}, "404": {"POST": 3, "GET": 13}}
 
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        // Let's see what the scrape would yield, but exclude the memstats metrics.
 
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        metricStrings := []string{}
 
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        metric := dto.Metric{}
 
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        metricChan := make(chan prometheus.Metric)
 
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        go func() {
 
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                expvarCollector.Collect(metricChan)
 
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                close(metricChan)
 
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        }()
 
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        for m := range metricChan {
 
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                if strings.Index(m.Desc().String(), "expvar_memstats") == -1 {
 
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                        metric.Reset()
 
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                        m.Write(&metric)
 
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                        metricStrings = append(metricStrings, metric.String())
 
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                }
 
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        }
 
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        sort.Strings(metricStrings)
 
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        for _, s := range metricStrings {
 
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                fmt.Println(strings.TrimRight(s, " "))
 
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        }
 
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        // Output:
 
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        // label:<name:"code" value:"200" > label:<name:"method" value:"GET" > untyped:<value:212 >
 
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        // label:<name:"code" value:"200" > label:<name:"method" value:"POST" > untyped:<value:11 >
 
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        // label:<name:"code" value:"404" > label:<name:"method" value:"GET" > untyped:<value:13 >
 
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        // label:<name:"code" value:"404" > label:<name:"method" value:"POST" > untyped:<value:3 >
 
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        // untyped:<value:42 >
 
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}