mirror of
				https://github.com/coredns/coredns.git
				synced 2025-10-30 17:53:21 -04:00 
			
		
		
		
	
		
			
				
	
	
		
			122 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| package metrics
 | |
| 
 | |
| import (
 | |
| 	"log"
 | |
| 	"net"
 | |
| 	"net/http"
 | |
| 	"sync"
 | |
| 
 | |
| 	"github.com/miekg/coredns/middleware"
 | |
| 
 | |
| 	"github.com/prometheus/client_golang/prometheus"
 | |
| )
 | |
| 
 | |
| var (
 | |
| 	requestCount    *prometheus.CounterVec
 | |
| 	requestDuration *prometheus.HistogramVec
 | |
| 	requestSize     *prometheus.HistogramVec
 | |
| 	requestDo       *prometheus.CounterVec
 | |
| 
 | |
| 	responseSize  *prometheus.HistogramVec
 | |
| 	responseRcode *prometheus.CounterVec
 | |
| )
 | |
| 
 | |
| // Metrics holds the prometheus configuration. The metrics' path is fixed to be /metrics
 | |
| type Metrics struct {
 | |
| 	Next      middleware.Handler
 | |
| 	Addr      string
 | |
| 	ln        net.Listener
 | |
| 	mux       *http.ServeMux
 | |
| 	Once      sync.Once
 | |
| 	ZoneNames []string
 | |
| }
 | |
| 
 | |
| func (m *Metrics) Start() error {
 | |
| 	m.Once.Do(func() {
 | |
| 		define()
 | |
| 
 | |
| 		if ln, err := net.Listen("tcp", m.Addr); err != nil {
 | |
| 			log.Printf("[ERROR] Failed to start metrics handler: %s", err)
 | |
| 			return
 | |
| 		} else {
 | |
| 			m.ln = ln
 | |
| 		}
 | |
| 		m.mux = http.NewServeMux()
 | |
| 
 | |
| 		prometheus.MustRegister(requestCount)
 | |
| 		prometheus.MustRegister(requestDuration)
 | |
| 		prometheus.MustRegister(requestSize)
 | |
| 		prometheus.MustRegister(requestDo)
 | |
| 		prometheus.MustRegister(responseSize)
 | |
| 		prometheus.MustRegister(responseRcode)
 | |
| 
 | |
| 		m.mux.Handle(path, prometheus.Handler())
 | |
| 
 | |
| 		go func() {
 | |
| 			http.Serve(m.ln, m.mux)
 | |
| 		}()
 | |
| 	})
 | |
| 	return nil
 | |
| }
 | |
| 
 | |
| func (m *Metrics) Shutdown() error {
 | |
| 	if m.ln != nil {
 | |
| 		return m.ln.Close()
 | |
| 	}
 | |
| 	return nil
 | |
| }
 | |
| 
 | |
| func define() {
 | |
| 	requestCount = prometheus.NewCounterVec(prometheus.CounterOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "request_count_total",
 | |
| 		Help:      "Counter of DNS requests made per zone, protocol and family.",
 | |
| 	}, []string{"zone", "proto", "family"})
 | |
| 
 | |
| 	requestDuration = prometheus.NewHistogramVec(prometheus.HistogramOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "request_duration_seconds",
 | |
| 		Buckets:   append([]float64{.0001, .0005, .001, .0025}, prometheus.DefBuckets...),
 | |
| 		Help:      "Histogram of the time (in seconds) each request took.",
 | |
| 	}, []string{"zone"})
 | |
| 
 | |
| 	requestSize = prometheus.NewHistogramVec(prometheus.HistogramOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "request_size_bytes",
 | |
| 		Help:      "Size of the EDNS0 UDP buffer in bytes (64K for TCP).",
 | |
| 		Buckets:   []float64{0, 100, 200, 300, 400, 511, 1023, 2047, 4095, 8291, 16e3, 32e3, 48e3, 64e3},
 | |
| 	}, []string{"zone"})
 | |
| 
 | |
| 	requestDo = prometheus.NewCounterVec(prometheus.CounterOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "request_do_count_total",
 | |
| 		Help:      "Counter of DNS requests with DO bit set per zone.",
 | |
| 	}, []string{"zone"})
 | |
| 
 | |
| 	responseSize = prometheus.NewHistogramVec(prometheus.HistogramOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "response_size_bytes",
 | |
| 		Help:      "Size of the returns response in bytes.",
 | |
| 		Buckets:   []float64{0, 100, 200, 300, 400, 511, 1023, 2047, 4095, 8291, 16e3, 32e3, 48e3, 64e3},
 | |
| 	}, []string{"zone"})
 | |
| 
 | |
| 	responseRcode = prometheus.NewCounterVec(prometheus.CounterOpts{
 | |
| 		Namespace: middleware.Namespace,
 | |
| 		Subsystem: subsystem,
 | |
| 		Name:      "response_rcode_count_total",
 | |
| 		Help:      "Counter of response status codes.",
 | |
| 	}, []string{"zone", "rcode"})
 | |
| }
 | |
| 
 | |
| const (
 | |
| 	// Dropped indicates we dropped the query before any handling. It has no closing dot, so it can not be a valid zone.
 | |
| 	Dropped   = "dropped"
 | |
| 	subsystem = "dns"
 | |
| 	path      = "/metrics"
 | |
| )
 |