feat(observabillity): #115 integrate otel for metrics and traces

internal/handler/middleware/cache_control.go

@@ -3,10 +3,15 @@ package middleware
 import (
 	"net/http"
 	"strings"
+
+	"go.opentelemetry.io/otel"
 )
 
 func CacheControl(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		counter, _ := otel.Meter("").Int64Counter("spend.sparrow.test")
+		counter.Add(r.Context(), 1)
+
 		shouldCache := strings.HasPrefix(r.URL.Path, "/static")
 
 		if !shouldCache {

internal/handler/middleware/cross_site_request_forgery.go

@@ -46,7 +46,7 @@ func CrossSiteRequestForgery(auth service.Auth) func(http.Handler) http.Handler
 				csrfToken := r.Header.Get("Csrf-Token")
 
 				if session == nil || csrfToken == "" || !auth.IsCsrfTokenValid(csrfToken, session.Id) {
-					log.Info("CSRF-Token \"%s\" not correct", csrfToken)
+					log.L.Info("CSRF-Token not correct", "token", csrfToken)
 					if r.Header.Get("Hx-Request") == "true" {
 						utils.TriggerToastWithStatus(w, r, "error", "CSRF-Token not correct", http.StatusBadRequest)
 					} else {

internal/handler/middleware/gzip.go

@@ -34,7 +34,7 @@ func Gzip(next http.Handler) http.Handler {
 
 		err := gz.Close()
 		if err != nil && !errors.Is(err, http.ErrBodyNotAllowed) {
-			log.Error("Gzip: could not close Writer: %v", err)
+			log.L.Error("Gzip: could not close Writer", "err", err)
 		}
 	})
 }

internal/handler/middleware/logger.go

@@ -2,23 +2,8 @@ package middleware
 
 import (
 	"net/http"
-	"strconv"
-	"time"
-
 	"spend-sparrow/internal/log"
-
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
-)
-
-var (
-	metrics = promauto.NewCounterVec(
-		prometheus.CounterOpts{
-			Name: "mefit_request_total",
-			Help: "The total number of requests processed",
-		},
-		[]string{"path", "method", "status"},
-	)
+	"time"
 )
 
 type WrappedWriter struct {
@@ -35,13 +20,19 @@ func Log(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		start := time.Now()
 
+		log.L.Info("request pattern", "pattern", r.Pattern)
+
 		wrapped := &WrappedWriter{
 			ResponseWriter: w,
 			StatusCode:     http.StatusOK,
 		}
 		next.ServeHTTP(wrapped, r)
 
-		log.Info(r.RemoteAddr + " " + strconv.Itoa(wrapped.StatusCode) + " " + r.Method + " " + r.URL.Path + " " + time.Since(start).String())
-		metrics.WithLabelValues(r.URL.Path, r.Method, http.StatusText(wrapped.StatusCode)).Inc()
+		log.L.Info("request",
+			"remoteAddr", r.RemoteAddr,
+			"status", wrapped.StatusCode,
+			"method", r.Method,
+			"path", r.URL.Path,
+			"duration", time.Since(start).String())
 	})
 }