client_golang/prometheus/go_collector_test.go

59 lines
1.0 KiB
Go

package prometheus
import (
"reflect"
"testing"
"time"
dto "github.com/prometheus/client_model/go"
)
func TestGoCollector(t *testing.T) {
var (
c = NewGoCollector()
ch = make(chan Metric)
waitc = make(chan struct{})
closec = make(chan struct{})
old = -1
)
defer close(closec)
go func() {
c.Collect(ch)
go func(c <-chan struct{}) {
<-c
}(closec)
<-waitc
c.Collect(ch)
}()
for {
select {
case metric := <-ch:
switch m := metric.(type) {
// Attention, this also catches Counter...
case Gauge:
pb := &dto.Metric{}
m.Write(pb)
if old == -1 {
old = int(pb.GetGauge().GetValue())
close(waitc)
continue
}
if diff := int(pb.GetGauge().GetValue()) - old; diff != 1 {
// TODO: This is flaky in highly concurrent situations.
t.Errorf("want 1 new goroutine, got %d", diff)
}
return
default:
t.Errorf("want type Gauge, got %s", reflect.TypeOf(metric))
}
case <-time.After(1 * time.Second):
t.Fatalf("expected collect timed out")
}
}
}