Something went wrong. Try again.
Monorepo for Tangled
Something went wrong. Try again.
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556package metrics
import ( "bufio" "fmt" "net" "net/http" "time"
"github.com/go-chi/chi/v5" "github.com/samber/lo")
type statusRecorder struct { http.ResponseWriter status int}
func (r *statusRecorder) WriteHeader(status int) { r.status = status r.ResponseWriter.WriteHeader(status)}
func (r *statusRecorder) Hijack() (net.Conn, *bufio.ReadWriter, error) { h, ok := r.ResponseWriter.(http.Hijacker) if !ok { return nil, nil, fmt.Errorf("underlying ResponseWriter does not support hijacking") } return h.Hijack()}
func Middleware(next http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { rec := &statusRecorder{ResponseWriter: w, status: http.StatusOK} start := time.Now() returned := false
defer func() { // use the matched route pattern to avoid high cardinality routePattern := chi.RouteContext(r.Context()).RoutePattern() if routePattern == "" { routePattern = "unknown" }
status := lo.Ternary(returned, fmt.Sprintf("%d", rec.status), "aborted") duration := time.Since(start).Seconds()
HttpRequestsTotal.WithLabelValues(r.Method, routePattern, status).Inc() HttpRequestDuration.WithLabelValues(r.Method, routePattern, status).Observe(duration) }()
next.ServeHTTP(rec, r) returned = true })}