Function instrumentHandlerCounter

metrics.go:53–62

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.

(counter *prometheus.CounterVec, next http.Handler)

// 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":   metrics.SanitizeCode(d.status),
			"method": metrics.SanitizeMethod(r.Method),
		}).Inc()
	})
}

func newDelegator(w http.ResponseWriter) *delegator {
	return &delegator{