Add logger middleware on DNS server

Author: albertcolom

cmd/server/dns.go

@@ -12,9 +12,9 @@ func StartDNSServer(service dns.Service, addr, net string) (*server.Server, chan
 	dnsServer := server.NewDnsServer(service, addr, net)
 
 	go func() {
-		log.Printf("Starting DNS server on %s (%s)", addr, net)
+		log.Printf("[DNS] Starting server on %s (%s)", addr, net)
 		if err := dnsServer.Start(); err != nil {
-			errChan <- fmt.Errorf("DNS server error: %w", err)
+			errChan <- fmt.Errorf("[DNS] Server error: %w", err)
 		}
 	}()
 

cmd/server/http.go

@@ -14,9 +14,9 @@ func StartHTTPServer(service dns.Service, addr, token string) (*http.Server, cha
 	httpServer := http.NewHTTPServer(handler, addr, token)
 
 	go func() {
-		log.Printf("Starting HTTP server on %s", addr)
+		log.Printf("[HTTP] Starting server on %s", addr)
 		if err := httpServer.Start(); err != nil {
-			errChan <- fmt.Errorf("HTTP server error: %w", err)
+			errChan <- fmt.Errorf("[HTTP] Server error: %w", err)
 		}
 	}()
 

cmd/server/shutdown.go

@@ -34,18 +34,18 @@ func WaitForShutdown(cancel context.CancelFunc, dnsServer *dns.Server, httpServe
 	go func() {
 		defer wg.Done()
 		if err := dnsServer.Shutdown(shutdownCtx); err != nil {
-			log.Printf("DNS server shutdown error: %v", err)
+			log.Printf("[DNS] Server shutdown error: %v", err)
 		} else {
-			log.Println("DNS server stopped gracefully")
+			log.Println("[DNS] Server stopped gracefully")
 		}
 	}()
 
 	go func() {
 		defer wg.Done()
 		if err := httpServer.Shutdown(shutdownCtx); err != nil {
-			log.Printf("HTTP server shutdown error: %v", err)
+			log.Printf("[HTTP] Server shutdown error: %v", err)
 		} else {
-			log.Println("HTTP server stopped gracefully")
+			log.Println("[HTTP] Server stopped gracefully")
 		}
 	}()
 

internal/adapters/dns/middleware/logger.go

@@ -0,0 +1,30 @@
+package middleware
+
+import (
+	"github.com/miekg/dns"
+	"log"
+	"net"
+	"time"
+)
+
+func LoggingMiddleware(next dns.HandlerFunc) dns.HandlerFunc {
+	return func(w dns.ResponseWriter, r *dns.Msg) {
+		start := time.Now()
+
+		next(w, r)
+
+		var domain, qType string
+		if len(r.Question) > 0 {
+			domain = r.Question[0].Name
+			qType = dns.TypeToString[r.Question[0].Qtype]
+		}
+
+		duration := time.Since(start)
+		clientIP, _, _ := net.SplitHostPort(w.RemoteAddr().String())
+		rCode := dns.RcodeToString[r.Rcode]
+
+		log.Printf("[DNS] %s IN %s | %s | %s | %s",
+			domain, qType, rCode, duration, clientIP,
+		)
+	}
+}

internal/adapters/dns/server.go

@@ -3,6 +3,7 @@ package dns
 import (
 	"context"
 	server "github.com/miekg/dns"
+	"go-dyndns/internal/adapters/dns/middleware"
 	"go-dyndns/internal/core/dns"
 )
 
@@ -13,7 +14,7 @@ type Server struct {
 func NewDnsServer(service dns.Service, addr, net string) *Server {
 	handler := NewDnsHandler(service)
 	dnsServer := &server.Server{Addr: addr, Net: net}
-	server.HandleFunc(".", handler.HandleDNSRequest)
+	server.HandleFunc(".", middleware.LoggingMiddleware(handler.HandleDNSRequest))
 
 	return &Server{DnsServer: dnsServer}