headscale/hscontrol/metrics.go

116 lines
3.7 KiB
Go

package hscontrol
import (
"net/http"
"strconv"
"github.com/gorilla/mux"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promauto"
"tailscale.com/envknob"
)
var debugHighCardinalityMetrics = envknob.Bool("HEADSCALE_DEBUG_HIGH_CARDINALITY_METRICS")
var mapResponseLastSentSeconds *prometheus.GaugeVec
func init() {
if debugHighCardinalityMetrics {
mapResponseLastSentSeconds = promauto.NewGaugeVec(prometheus.GaugeOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_last_sent_seconds",
Help: "last sent metric to node.id",
}, []string{"type", "id"})
}
}
const prometheusNamespace = "headscale"
var (
mapResponseSent = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_sent_total",
Help: "total count of mapresponses sent to clients",
}, []string{"status", "type"})
mapResponseUpdateReceived = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_updates_received_total",
Help: "total count of mapresponse updates received on update channel",
}, []string{"type"})
mapResponseEndpointUpdates = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_endpoint_updates_total",
Help: "total count of endpoint updates received",
}, []string{"status"})
mapResponseReadOnly = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_readonly_requests_total",
Help: "total count of readonly requests received",
}, []string{"status"})
mapResponseEnded = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_ended_total",
Help: "total count of new mapsessions ended",
}, []string{"reason"})
mapResponseClosed = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "mapresponse_closed_total",
Help: "total count of calls to mapresponse close",
}, []string{"return"})
httpDuration = promauto.NewHistogramVec(prometheus.HistogramOpts{
Namespace: prometheusNamespace,
Name: "http_duration_seconds",
Help: "Duration of HTTP requests.",
}, []string{"path"})
httpCounter = promauto.NewCounterVec(prometheus.CounterOpts{
Namespace: prometheusNamespace,
Name: "http_requests_total",
Help: "Total number of http requests processed",
}, []string{"code", "method", "path"},
)
)
// prometheusMiddleware implements mux.MiddlewareFunc.
func prometheusMiddleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
route := mux.CurrentRoute(r)
path, _ := route.GetPathTemplate()
// Ignore streaming and noise sessions
// it has its own router further down.
if path == "/ts2021" || path == "/machine/map" || path == "/derp" || path == "/derp/probe" || path == "/derp/latency-check" || path == "/bootstrap-dns" {
next.ServeHTTP(w, r)
return
}
rw := &respWriterProm{ResponseWriter: w}
timer := prometheus.NewTimer(httpDuration.WithLabelValues(path))
next.ServeHTTP(rw, r)
timer.ObserveDuration()
httpCounter.WithLabelValues(strconv.Itoa(rw.status), r.Method, path).Inc()
})
}
type respWriterProm struct {
http.ResponseWriter
status int
written int64
wroteHeader bool
}
func (r *respWriterProm) WriteHeader(code int) {
r.status = code
r.wroteHeader = true
r.ResponseWriter.WriteHeader(code)
}
func (r *respWriterProm) Write(b []byte) (int, error) {
if !r.wroteHeader {
r.WriteHeader(http.StatusOK)
}
n, err := r.ResponseWriter.Write(b)
r.written += int64(n)
return n, err
}