traefik/pkg/metrics/opentelemetry_test.go
Romain 5fd6913ee5
Fix OpenTelemetry metrics
Co-authored-by: LandryBe <[lbenguigui@gmail.com](mailto:lbenguigui@gmail.com)>
2023-06-20 09:12:05 +02:00

450 lines
22 KiB
Go

package metrics
import (
"compress/gzip"
"context"
"encoding/json"
"io"
"net/http"
"net/http/httptest"
"net/url"
"strconv"
"testing"
"time"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
ptypes "github.com/traefik/paerser/types"
"github.com/traefik/traefik/v3/pkg/types"
"github.com/traefik/traefik/v3/pkg/version"
"go.opentelemetry.io/collector/pdata/pmetric/pmetricotlp"
"go.opentelemetry.io/otel/attribute"
)
func TestOpenTelemetry_labels(t *testing.T) {
tests := []struct {
desc string
values otelLabelNamesValues
with []string
expect []attribute.KeyValue
}{
{
desc: "with no starting value",
values: otelLabelNamesValues{},
expect: []attribute.KeyValue{},
},
{
desc: "with one starting value",
values: otelLabelNamesValues{"foo"},
expect: []attribute.KeyValue{},
},
{
desc: "with two starting value",
values: otelLabelNamesValues{"foo", "bar"},
expect: []attribute.KeyValue{attribute.String("foo", "bar")},
},
{
desc: "with no starting value, and with one other value",
values: otelLabelNamesValues{},
with: []string{"baz"},
expect: []attribute.KeyValue{attribute.String("baz", "unknown")},
},
{
desc: "with no starting value, and with two other value",
values: otelLabelNamesValues{},
with: []string{"baz", "buz"},
expect: []attribute.KeyValue{attribute.String("baz", "buz")},
},
{
desc: "with one starting value, and with one other value",
values: otelLabelNamesValues{"foo"},
with: []string{"baz"},
expect: []attribute.KeyValue{attribute.String("foo", "baz")},
},
{
desc: "with one starting value, and with two other value",
values: otelLabelNamesValues{"foo"},
with: []string{"baz", "buz"},
expect: []attribute.KeyValue{attribute.String("foo", "baz")},
},
{
desc: "with two starting value, and with one other value",
values: otelLabelNamesValues{"foo", "bar"},
with: []string{"baz"},
expect: []attribute.KeyValue{
attribute.String("foo", "bar"),
attribute.String("baz", "unknown"),
},
},
{
desc: "with two starting value, and with two other value",
values: otelLabelNamesValues{"foo", "bar"},
with: []string{"baz", "buz"},
expect: []attribute.KeyValue{
attribute.String("foo", "bar"),
attribute.String("baz", "buz"),
},
},
}
for _, test := range tests {
test := test
t.Run(test.desc, func(t *testing.T) {
t.Parallel()
assert.Equal(t, test.expect, test.values.With(test.with...).ToLabels())
})
}
}
func TestOpenTelemetry_GaugeCollectorAdd(t *testing.T) {
tests := []struct {
desc string
gc *gaugeCollector
delta float64
name string
attributes otelLabelNamesValues
expect map[string]map[string]gaugeValue
}{
{
desc: "empty collector",
gc: newOpenTelemetryGaugeCollector(),
delta: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
{
desc: "initialized collector",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
delta: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {"": {value: 2}},
},
},
{
desc: "initialized collector, values with label (only the last one counts)",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {
"bar": {
attributes: otelLabelNamesValues{"bar"},
value: 1,
},
},
},
},
delta: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {
"": {
value: 1,
},
"bar": {
attributes: otelLabelNamesValues{"bar"},
value: 1,
},
},
},
},
{
desc: "initialized collector, values with label on set",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {"bar": {value: 1}},
},
},
delta: 1,
name: "foo",
attributes: otelLabelNamesValues{"baz"},
expect: map[string]map[string]gaugeValue{
"foo": {
"bar": {
value: 1,
},
"baz": {
value: 1,
attributes: otelLabelNamesValues{"baz"},
},
},
},
},
}
for _, test := range tests {
test := test
t.Run(test.desc, func(t *testing.T) {
t.Parallel()
test.gc.add(test.name, test.delta, test.attributes)
assert.Equal(t, test.expect, test.gc.values)
})
}
}
func TestOpenTelemetry_GaugeCollectorSet(t *testing.T) {
tests := []struct {
desc string
gc *gaugeCollector
value float64
name string
attributes otelLabelNamesValues
expect map[string]map[string]gaugeValue
}{
{
desc: "empty collector",
gc: newOpenTelemetryGaugeCollector(),
value: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
{
desc: "initialized collector",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
value: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
{
desc: "initialized collector, values with label",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {
"bar": {
attributes: otelLabelNamesValues{"bar"},
value: 1,
},
},
},
},
value: 1,
name: "foo",
expect: map[string]map[string]gaugeValue{
"foo": {
"": {
value: 1,
},
"bar": {
attributes: otelLabelNamesValues{"bar"},
value: 1,
},
},
},
},
{
desc: "initialized collector, values with label on set",
gc: &gaugeCollector{
values: map[string]map[string]gaugeValue{
"foo": {"": {value: 1}},
},
},
value: 1,
name: "foo",
attributes: otelLabelNamesValues{"bar"},
expect: map[string]map[string]gaugeValue{
"foo": {
"": {
value: 1,
},
"bar": {
value: 1,
attributes: otelLabelNamesValues{"bar"},
},
},
},
},
}
for _, test := range tests {
test := test
t.Run(test.desc, func(t *testing.T) {
t.Parallel()
test.gc.set(test.name, test.value, test.attributes)
assert.Equal(t, test.expect, test.gc.values)
})
}
}
func TestOpenTelemetry(t *testing.T) {
t.Parallel()
c := make(chan *string)
defer close(c)
ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
gzr, err := gzip.NewReader(r.Body)
require.NoError(t, err)
body, err := io.ReadAll(gzr)
require.NoError(t, err)
req := pmetricotlp.NewExportRequest()
err = req.UnmarshalProto(body)
require.NoError(t, err)
marshalledReq, err := json.Marshal(req)
require.NoError(t, err)
bodyStr := string(marshalledReq)
c <- &bodyStr
w.WriteHeader(http.StatusOK)
}))
defer ts.Close()
sURL, err := url.Parse(ts.URL)
require.NoError(t, err)
var cfg types.OpenTelemetry
(&cfg).SetDefaults()
cfg.AddRoutersLabels = true
cfg.Address = sURL.Host
cfg.Insecure = true
cfg.PushInterval = ptypes.Duration(10 * time.Millisecond)
registry := RegisterOpenTelemetry(context.Background(), &cfg)
require.NotNil(t, registry)
if !registry.IsEpEnabled() || !registry.IsRouterEnabled() || !registry.IsSvcEnabled() {
t.Fatalf("registry should return true for IsEnabled(), IsRouterEnabled() and IsSvcEnabled()")
}
expected := []string{
`({"key":"service.name","value":{"stringValue":"traefik"}})`,
`({"key":"service.version","value":{"stringValue":"` + version.Version + `"}})`,
}
msgMisc := <-c
assertMessage(t, *msgMisc, expected)
// TODO: the len of startUnixNano is no supposed to be 20, it should be 19
expected = append(expected,
`({"name":"traefik_config_reloads_total","description":"Config reloads","unit":"1","sum":{"dataPoints":\[{"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_config_last_reload_success","description":"Last config reload success","unit":"ms","gauge":{"dataPoints":\[{"startTimeUnixNano":"[\d]{20}","timeUnixNano":"[\d]{19}","asDouble":1}\]}})`,
`({"name":"traefik_open_connections","description":"How many open connections exist, by entryPoint and protocol","unit":"1","gauge":{"dataPoints":\[{"attributes":\[{"key":"entrypoint","value":{"stringValue":"test"}},{"key":"protocol","value":{"stringValue":"TCP"}}\],"startTimeUnixNano":"[\d]{20}","timeUnixNano":"[\d]{19}","asDouble":1}\]}})`,
)
registry.ConfigReloadsCounter().Add(1)
registry.LastConfigReloadSuccessGauge().Set(1)
registry.OpenConnectionsGauge().With("entrypoint", "test", "protocol", "TCP").Set(1)
msgServer := <-c
assertMessage(t, *msgServer, expected)
expected = append(expected,
`({"name":"traefik_tls_certs_not_after","description":"Certificate expiration timestamp","unit":"ms","gauge":{"dataPoints":\[{"attributes":\[{"key":"key","value":{"stringValue":"value"}}\],"startTimeUnixNano":"[\d]{20}","timeUnixNano":"[\d]{19}","asDouble":1}\]}})`,
)
registry.TLSCertsNotAfterTimestampGauge().With("key", "value").Set(1)
msgTLS := <-c
assertMessage(t, *msgTLS, expected)
expected = append(expected,
`({"name":"traefik_entrypoint_requests_total","description":"How many HTTP requests processed on an entrypoint, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"200"}},{"key":"entrypoint","value":{"stringValue":"test1"}},{"key":"method","value":{"stringValue":"GET"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_entrypoint_requests_tls_total","description":"How many HTTP requests with TLS processed on an entrypoint, partitioned by TLS Version and TLS cipher Used.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"entrypoint","value":{"stringValue":"test2"}},{"key":"tls_cipher","value":{"stringValue":"bar"}},{"key":"tls_version","value":{"stringValue":"foo"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_entrypoint_request_duration_seconds","description":"How long it took to process the request on an entrypoint, partitioned by status code, protocol, and method.","unit":"ms","histogram":{"dataPoints":\[{"attributes":\[{"key":"entrypoint","value":{"stringValue":"test3"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","count":"1","sum":10000,"bucketCounts":\["0","0","0","0","0","0","0","0","0","0","0","1"\],"explicitBounds":\[0.005,0.01,0.025,0.05,0.1,0.25,0.5,1,2.5,5,10\],"min":10000,"max":10000}\],"aggregationTemporality":2}})`,
`({"name":"traefik_entrypoint_requests_bytes_total","description":"The total size of requests in bytes handled by an entrypoint, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"200"}},{"key":"entrypoint","value":{"stringValue":"test1"}},{"key":"method","value":{"stringValue":"GET"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_entrypoint_responses_bytes_total","description":"The total size of responses in bytes handled by an entrypoint, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"200"}},{"key":"entrypoint","value":{"stringValue":"test1"}},{"key":"method","value":{"stringValue":"GET"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
)
registry.EntryPointReqsCounter().With(nil, "entrypoint", "test1", "code", strconv.Itoa(http.StatusOK), "method", http.MethodGet).Add(1)
registry.EntryPointReqsTLSCounter().With("entrypoint", "test2", "tls_version", "foo", "tls_cipher", "bar").Add(1)
registry.EntryPointReqDurationHistogram().With("entrypoint", "test3").Observe(10000)
registry.EntryPointReqsBytesCounter().With("entrypoint", "test1", "code", strconv.Itoa(http.StatusOK), "method", http.MethodGet).Add(1)
registry.EntryPointRespsBytesCounter().With("entrypoint", "test1", "code", strconv.Itoa(http.StatusOK), "method", http.MethodGet).Add(1)
msgEntrypoint := <-c
assertMessage(t, *msgEntrypoint, expected)
expected = append(expected,
`({"name":"traefik_router_requests_total","description":"How many HTTP requests are processed on a router, partitioned by service, status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"(?:200|404)"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"router","value":{"stringValue":"RouterReqsCounter"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1},{"attributes":\[{"key":"code","value":{"stringValue":"(?:200|404)"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"router","value":{"stringValue":"RouterReqsCounter"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_router_requests_tls_total","description":"How many HTTP requests with TLS are processed on a router, partitioned by service, TLS Version, and TLS cipher Used.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"router","value":{"stringValue":"demo"}},{"key":"service","value":{"stringValue":"test"}},{"key":"tls_cipher","value":{"stringValue":"bar"}},{"key":"tls_version","value":{"stringValue":"foo"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_router_request_duration_seconds","description":"How long it took to process the request on a router, partitioned by service, status code, protocol, and method.","unit":"ms","histogram":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"200"}},{"key":"router","value":{"stringValue":"demo"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","count":"1","sum":10000,"bucketCounts":\["0","0","0","0","0","0","0","0","0","0","0","1"\],"explicitBounds":\[0.005,0.01,0.025,0.05,0.1,0.25,0.5,1,2.5,5,10\],"min":10000,"max":10000}\],"aggregationTemporality":2}})`,
`({"name":"traefik_router_requests_bytes_total","description":"The total size of requests in bytes handled by a router, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"404"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"router","value":{"stringValue":"RouterReqsCounter"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_router_responses_bytes_total","description":"The total size of responses in bytes handled by a router, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"404"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"router","value":{"stringValue":"RouterReqsCounter"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
)
registry.RouterReqsCounter().With(nil, "router", "RouterReqsCounter", "service", "test", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
registry.RouterReqsCounter().With(nil, "router", "RouterReqsCounter", "service", "test", "code", strconv.Itoa(http.StatusOK), "method", http.MethodGet).Add(1)
registry.RouterReqsTLSCounter().With("router", "demo", "service", "test", "tls_version", "foo", "tls_cipher", "bar").Add(1)
registry.RouterReqDurationHistogram().With("router", "demo", "service", "test", "code", strconv.Itoa(http.StatusOK)).Observe(10000)
registry.RouterReqsBytesCounter().With("router", "RouterReqsCounter", "service", "test", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
registry.RouterRespsBytesCounter().With("router", "RouterReqsCounter", "service", "test", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
msgRouter := <-c
assertMessage(t, *msgRouter, expected)
expected = append(expected,
`({"name":"traefik_service_requests_total","description":"How many HTTP requests processed on a service, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"(?:200|404)"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"service","value":{"stringValue":"ServiceReqsCounter"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1},{"attributes":\[{"key":"code","value":{"stringValue":"(?:200|404)"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"service","value":{"stringValue":"ServiceReqsCounter"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_service_requests_tls_total","description":"How many HTTP requests with TLS processed on a service, partitioned by TLS version and TLS cipher.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"service","value":{"stringValue":"test"}},{"key":"tls_cipher","value":{"stringValue":"bar"}},{"key":"tls_version","value":{"stringValue":"foo"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_service_request_duration_seconds","description":"How long it took to process the request on a service, partitioned by status code, protocol, and method.","unit":"ms","histogram":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"200"}},{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","count":"1","sum":10000,"bucketCounts":\["0","0","0","0","0","0","0","0","0","0","0","1"\],"explicitBounds":\[0.005,0.01,0.025,0.05,0.1,0.25,0.5,1,2.5,5,10\],"min":10000,"max":10000}\],"aggregationTemporality":2}})`,
`({"name":"traefik_service_server_up","description":"service server is up, described by gauge value of 0 or 1.","unit":"1","gauge":{"dataPoints":\[{"attributes":\[{"key":"service","value":{"stringValue":"test"}},{"key":"url","value":{"stringValue":"http://127.0.0.1"}}\],"startTimeUnixNano":"[\d]{20}","timeUnixNano":"[\d]{19}","asDouble":1}\]}})`,
`({"name":"traefik_service_requests_bytes_total","description":"The total size of requests in bytes received by a service, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"404"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"service","value":{"stringValue":"ServiceReqsCounter"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
`({"name":"traefik_service_responses_bytes_total","description":"The total size of responses in bytes returned by a service, partitioned by status code, protocol, and method.","unit":"1","sum":{"dataPoints":\[{"attributes":\[{"key":"code","value":{"stringValue":"404"}},{"key":"method","value":{"stringValue":"GET"}},{"key":"service","value":{"stringValue":"ServiceReqsCounter"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1}\],"aggregationTemporality":2,"isMonotonic":true}})`,
)
registry.ServiceReqsCounter().With(nil, "service", "ServiceReqsCounter", "code", strconv.Itoa(http.StatusOK), "method", http.MethodGet).Add(1)
registry.ServiceReqsCounter().With(nil, "service", "ServiceReqsCounter", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
registry.ServiceReqsTLSCounter().With("service", "test", "tls_version", "foo", "tls_cipher", "bar").Add(1)
registry.ServiceReqDurationHistogram().With("service", "test", "code", strconv.Itoa(http.StatusOK)).Observe(10000)
registry.ServiceServerUpGauge().With("service", "test", "url", "http://127.0.0.1").Set(1)
registry.ServiceReqsBytesCounter().With("service", "ServiceReqsCounter", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
registry.ServiceRespsBytesCounter().With("service", "ServiceReqsCounter", "code", strconv.Itoa(http.StatusNotFound), "method", http.MethodGet).Add(1)
msgService := <-c
assertMessage(t, *msgService, expected)
expected = append(expected,
`({"attributes":\[{"key":"service","value":{"stringValue":"foobar"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":1})`,
`({"attributes":\[{"key":"service","value":{"stringValue":"test"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","asDouble":2})`,
)
registry.ServiceRetriesCounter().With("service", "test").Add(1)
registry.ServiceRetriesCounter().With("service", "test").Add(1)
registry.ServiceRetriesCounter().With("service", "foobar").Add(1)
msgServiceRetries := <-c
assertMessage(t, *msgServiceRetries, expected)
// We cannot rely on the previous expected pattern,
// because this pattern was for matching only one dataPoint in the histogram,
// and as soon as the EntryPointReqDurationHistogram.Observe is called,
// it adds a new dataPoint to the histogram.
expectedEntryPointReqDuration := []string{
`({"attributes":\[{"key":"entrypoint","value":{"stringValue":"myEntrypoint"}}\],"startTimeUnixNano":"[\d]{19}","timeUnixNano":"[\d]{19}","count":"2","sum":30000,"bucketCounts":\["0","0","0","0","0","0","0","0","0","0","0","2"\],"explicitBounds":\[0.005,0.01,0.025,0.05,0.1,0.25,0.5,1,2.5,5,10\],"min":10000,"max":20000})`,
}
registry.EntryPointReqDurationHistogram().With("entrypoint", "myEntrypoint").Observe(10000)
registry.EntryPointReqDurationHistogram().With("entrypoint", "myEntrypoint").Observe(20000)
msgEntryPointReqDurationHistogram := <-c
assertMessage(t, *msgEntryPointReqDurationHistogram, expectedEntryPointReqDuration)
// We need to unlock the HTTP Server for the last export call when stopping
// OpenTelemetry.
go func() {
<-c
}()
StopOpenTelemetry()
}