mirror of
https://github.com/caddyserver/caddy.git
synced 2024-12-16 21:56:40 -05:00
101 lines
2.9 KiB
Go
101 lines
2.9 KiB
Go
package caddy
|
|
|
|
import (
|
|
"net/http"
|
|
"strconv"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
"github.com/prometheus/client_golang/prometheus/collectors"
|
|
"github.com/prometheus/client_golang/prometheus/promauto"
|
|
)
|
|
|
|
// define and register the metrics used in this package.
|
|
func init() {
|
|
prometheus.MustRegister(collectors.NewBuildInfoCollector())
|
|
|
|
const ns, sub = "caddy", "admin"
|
|
|
|
adminMetrics.requestCount = promauto.NewCounterVec(prometheus.CounterOpts{
|
|
Namespace: ns,
|
|
Subsystem: sub,
|
|
Name: "http_requests_total",
|
|
Help: "Counter of requests made to the Admin API's HTTP endpoints.",
|
|
}, []string{"handler", "path", "code", "method"})
|
|
adminMetrics.requestErrors = promauto.NewCounterVec(prometheus.CounterOpts{
|
|
Namespace: ns,
|
|
Subsystem: sub,
|
|
Name: "http_request_errors_total",
|
|
Help: "Number of requests resulting in middleware errors.",
|
|
}, []string{"handler", "path", "method"})
|
|
}
|
|
|
|
// adminMetrics is a collection of metrics that can be tracked for the admin API.
|
|
var adminMetrics = struct {
|
|
requestCount *prometheus.CounterVec
|
|
requestErrors *prometheus.CounterVec
|
|
}{}
|
|
|
|
// Similar to promhttp.InstrumentHandlerCounter, but upper-cases method names
|
|
// instead of lower-casing them.
|
|
//
|
|
// Unlike promhttp.InstrumentHandlerCounter, this assumes a "code" and "method"
|
|
// label is present, and will panic otherwise.
|
|
func instrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
d := newDelegator(w)
|
|
next.ServeHTTP(d, r)
|
|
counter.With(prometheus.Labels{
|
|
"code": sanitizeCode(d.status),
|
|
"method": sanitizeMethod(r.Method),
|
|
}).Inc()
|
|
})
|
|
}
|
|
|
|
func newDelegator(w http.ResponseWriter) *delegator {
|
|
return &delegator{
|
|
ResponseWriter: w,
|
|
}
|
|
}
|
|
|
|
type delegator struct {
|
|
http.ResponseWriter
|
|
status int
|
|
}
|
|
|
|
func (d *delegator) WriteHeader(code int) {
|
|
d.status = code
|
|
d.ResponseWriter.WriteHeader(code)
|
|
}
|
|
|
|
func sanitizeCode(s int) string {
|
|
switch s {
|
|
case 0, 200:
|
|
return "200"
|
|
default:
|
|
return strconv.Itoa(s)
|
|
}
|
|
}
|
|
|
|
// Only support the list of "regular" HTTP methods, see
|
|
// https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods
|
|
var methodMap = map[string]string{
|
|
"GET": http.MethodGet, "get": http.MethodGet,
|
|
"HEAD": http.MethodHead, "head": http.MethodHead,
|
|
"PUT": http.MethodPut, "put": http.MethodPut,
|
|
"POST": http.MethodPost, "post": http.MethodPost,
|
|
"DELETE": http.MethodDelete, "delete": http.MethodDelete,
|
|
"CONNECT": http.MethodConnect, "connect": http.MethodConnect,
|
|
"OPTIONS": http.MethodOptions, "options": http.MethodOptions,
|
|
"TRACE": http.MethodTrace, "trace": http.MethodTrace,
|
|
"PATCH": http.MethodPatch, "patch": http.MethodPatch,
|
|
}
|
|
|
|
// sanitizeMethod sanitizes the method for use as a metric label. This helps
|
|
// prevent high cardinality on the method label. The name is always upper case.
|
|
func sanitizeMethod(m string) string {
|
|
if m, ok := methodMap[m]; ok {
|
|
return m
|
|
}
|
|
|
|
return "OTHER"
|
|
}
|