/
traffic_middleware.go
46 lines (39 loc) · 1.19 KB
/
traffic_middleware.go
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package http_server
import (
"github.com/paulrozhkin/sport-tracker/internal/metrics"
"net/http"
"regexp"
)
type TrafficMiddleware struct {
trafficMetrics *metrics.TrafficMetrics
regex *regexp.Regexp
}
type responseWriter struct {
http.ResponseWriter
statusCode int
}
func NewTrafficMiddleware(trafficMetrics *metrics.TrafficMetrics) (*TrafficMiddleware, error) {
re := regexp.MustCompile(`[\da-f]{8}-[\da-f]{4}-[\da-f]{4}-[\da-f]{4}-[\da-f]{12}`)
return &TrafficMiddleware{trafficMetrics: trafficMetrics, regex: re}, nil
}
func (tm *TrafficMiddleware) CalculateTraffic(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
uri := tm.regex.ReplaceAllString(r.RequestURI, `{id}`)
if uri == "/metrics" {
next.ServeHTTP(w, r)
return
}
timer := tm.trafficMetrics.GetTimer(uri)
rw := newResponseWriter(w)
next.ServeHTTP(rw, r)
timer.ObserveDuration()
tm.trafficMetrics.RequestHandled(uri, rw.statusCode)
})
}
func newResponseWriter(w http.ResponseWriter) *responseWriter {
return &responseWriter{w, http.StatusOK}
}
func (rw *responseWriter) WriteHeader(code int) {
rw.statusCode = code
rw.ResponseWriter.WriteHeader(code)
}