2338120f5b
This registers the Collectors iff the metrics plugin has been loaded. Safes a bunch of code in each and every plugin's setup code.
52 lines
1.1 KiB
Go
52 lines
1.1 KiB
Go
package health
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import (
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"net/http"
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"sync"
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"time"
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"github.com/coredns/coredns/plugin"
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"github.com/prometheus/client_golang/prometheus"
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)
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// overloaded queries the health end point and updates a metrics showing how long it took.
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func (h *health) overloaded() {
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timeout := time.Duration(5 * time.Second)
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client := http.Client{
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Timeout: timeout,
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}
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url := "http://" + h.Addr
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tick := time.NewTicker(1 * time.Second)
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for {
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select {
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case <-tick.C:
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start := time.Now()
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resp, err := client.Get(url)
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if err != nil {
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HealthDuration.Observe(timeout.Seconds())
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continue
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}
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resp.Body.Close()
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HealthDuration.Observe(time.Since(start).Seconds())
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case <-h.stop:
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tick.Stop()
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return
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}
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}
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}
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var (
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// HealthDuration is the metric used for exporting how fast we can retrieve the /health endpoint.
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HealthDuration = prometheus.NewHistogram(prometheus.HistogramOpts{
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Namespace: plugin.Namespace,
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Subsystem: "health",
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Name: "request_duration_seconds",
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Buckets: plugin.TimeBuckets,
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Help: "Histogram of the time (in seconds) each request took.",
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})
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)
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var once sync.Once
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