Exemple #1
0
func ExampleConstHistogram() {
	desc := prometheus.NewDesc(
		"http_request_duration_seconds",
		"A histogram of the HTTP request durations.",
		[]string{"code", "method"},
		prometheus.Labels{"owner": "example"},
	)

	// Create a constant histogram from values we got from a 3rd party telemetry system.
	h := prometheus.MustNewConstHistogram(
		desc,
		4711, 403.34,
		map[float64]uint64{25: 121, 50: 2403, 100: 3221, 200: 4233},
		"200", "get",
	)

	// Just for demonstration, let's check the state of the histogram by
	// (ab)using its Write method (which is usually only used by Prometheus
	// internally).
	metric := &dto.Metric{}
	h.Write(metric)
	fmt.Println(proto.MarshalTextString(metric))

	// Output:
	// label: <
	//   name: "code"
	//   value: "200"
	// >
	// label: <
	//   name: "method"
	//   value: "get"
	// >
	// label: <
	//   name: "owner"
	//   value: "example"
	// >
	// histogram: <
	//   sample_count: 4711
	//   sample_sum: 403.34
	//   bucket: <
	//     cumulative_count: 121
	//     upper_bound: 25
	//   >
	//   bucket: <
	//     cumulative_count: 2403
	//     upper_bound: 50
	//   >
	//   bucket: <
	//     cumulative_count: 3221
	//     upper_bound: 100
	//   >
	//   bucket: <
	//     cumulative_count: 4233
	//     upper_bound: 200
	//   >
	// >
}
func ExampleSelfCollector() {
	m := NewCallbackMetric(
		prometheus.NewDesc(
			"runtime_goroutines_count",
			"Total number of goroutines that currently exist.",
			nil, nil, // No labels, these must be nil.
		),
		func() float64 {
			return float64(runtime.NumGoroutine())
		},
	)
	prometheus.MustRegister(m)
}
Exemple #3
0
func ExampleConstSummary() {
	desc := prometheus.NewDesc(
		"http_request_duration_seconds",
		"A summary of the HTTP request durations.",
		[]string{"code", "method"},
		prometheus.Labels{"owner": "example"},
	)

	// Create a constant summary from values we got from a 3rd party telemetry system.
	s := prometheus.MustNewConstSummary(
		desc,
		4711, 403.34,
		map[float64]float64{0.5: 42.3, 0.9: 323.3},
		"200", "get",
	)

	// Just for demonstration, let's check the state of the summary by
	// (ab)using its Write method (which is usually only used by Prometheus
	// internally).
	metric := &dto.Metric{}
	s.Write(metric)
	fmt.Println(proto.MarshalTextString(metric))

	// Output:
	// label: <
	//   name: "code"
	//   value: "200"
	// >
	// label: <
	//   name: "method"
	//   value: "get"
	// >
	// label: <
	//   name: "owner"
	//   value: "example"
	// >
	// summary: <
	//   sample_count: 4711
	//   sample_sum: 403.34
	//   quantile: <
	//     quantile: 0.5
	//     value: 42.3
	//   >
	//   quantile: <
	//     quantile: 0.9
	//     value: 323.3
	//   >
	// >
}
Exemple #4
0
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 >
}
// 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 (
	"runtime"

	"github.com/coreos/etcd/Godeps/_workspace/src/github.com/prometheus/client_golang/prometheus"
)

var (
	allocDesc = prometheus.NewDesc(
		prometheus.BuildFQName("", "memstats", "alloc_bytes"),
		"bytes allocated and still in use",
		nil, nil,
	)
	totalAllocDesc = prometheus.NewDesc(
		prometheus.BuildFQName("", "memstats", "total_alloc_bytes"),
		"bytes allocated (even if freed)",
		nil, nil,
	)
	numGCDesc = prometheus.NewDesc(
		prometheus.BuildFQName("", "memstats", "num_gc_total"),
		"number of GCs run",
		nil, nil,
	)
)

// MemStatsCollector is an example for a custom Collector that solves the