feat: limit image request

cmd/schreifuchs-ch/main.go

@@ -3,14 +3,20 @@ package main
 import (
 	"context"
 	"log/slog"
+	"net/http"
 	"os"
 	"os/signal"
 
+	_ "net/http/pprof"
+
 	"git.schreifuchs.ch/schreifuchs/schreifuchs.ch/internal/pkg/config"
 	"git.schreifuchs.ch/schreifuchs/schreifuchs.ch/internal/server"
 )
 
 func main() {
+	go func() {
+		http.ListenAndServe("localhost:6060", nil)
+	}()
 	ctx := context.Background()
 	ctx, cancle := context.WithCancel(ctx)
 	defer cancle()

internal/components/images/controller.go

@@ -60,6 +60,13 @@ func (s *Service) getImage(uid string) (file []byte, mimeType string, err error)
 }
 
 func (s *Service) GetImage(ctx context.Context, uid string, options Options) (img io.Reader, mimeType string, err error) {
+	if err = s.seph.Acquire(ctx, 1); err != nil {
+		err = fmt.Errorf("could not Acquire semaphore: %w", err)
+		return
+
+	}
+	defer s.seph.Release(1)
+
 	rawImage, mimeType, err := s.getImage(uid)
 	if err != nil {
 		return

internal/components/images/resorce.go

@@ -4,6 +4,7 @@ import (
 	"os"
 
 	"github.com/valkey-io/valkey-go"
+	"golang.org/x/sync/semaphore"
 )
 
 type Options struct {
@@ -15,12 +16,14 @@ type Options struct {
 type Service struct {
 	fs    fileSystem
 	cache valkey.Client
+	seph  *semaphore.Weighted
 }
 
-func New(fs fileSystem, cache valkey.Client) *Service {
+func New(fs fileSystem, cache valkey.Client, maxConcurency int64) *Service {
 	return &Service{
 		fs:    fs,
 		cache: cache,
+		seph:  semaphore.NewWeighted(maxConcurency),
 	}
 }
 

internal/server/middlewares.go

@@ -0,0 +1,46 @@
+package server
+
+import (
+	"fmt"
+	"log/slog"
+	"net/http"
+	"time"
+)
+
+type captureWriter struct {
+	http.ResponseWriter
+	code int
+}
+
+func (c *captureWriter) WriteHeader(statusCode int) {
+	c.code = statusCode
+	c.ResponseWriter.WriteHeader(statusCode)
+}
+
+func (s *Server) loggingMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		cw := &captureWriter{
+			ResponseWriter: w,
+			code:           200,
+		}
+		next.ServeHTTP(cw, r)
+		slog.Info("request",
+			"method", r.Method,
+			"path", r.URL.Path,
+			"duration", time.Since(start),
+			"status", cw.code,
+		)
+	})
+}
+
+// cacheMiddleware adds Cache-Control headers to the response.
+func cacheMiddleware(maxAge time.Duration) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Cache-Control", fmt.Sprintf("public, max-age=%.0f", maxAge.Seconds()))
+			w.Header().Set("Vary", "HX-Request,Accept-Language,Accept-Encoding")
+			next.ServeHTTP(w, r)
+		})
+	}
+}

internal/server/routes.go

@@ -50,7 +50,7 @@ func (s *Server) registerOther() (h http.Handler) {
 	}
 
 	_ = resthome.New(mux, page.New(fs))
-	_ = restimage.New(mux, images.New(fs, valkeyClient))
+	_ = restimage.New(mux, images.New(fs, valkeyClient, 4))
 
 	mux.Handle("/", http.FileServer(http.FS(web.GetStaticFS())))
 
@@ -61,15 +61,3 @@ func (s *Server) registerOther() (h http.Handler) {
 	h = cacheMiddleware(time.Minute * 5)(h)
 	return h
 }
-
-func (s *Server) loggingMiddleware(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		start := time.Now()
-		next.ServeHTTP(w, r)
-		slog.Info("request",
-			"method", r.Method,
-			"path", r.URL.Path,
-			"duration", time.Since(start),
-		)
-	})
-}

internal/server/static.go

@@ -1,7 +1,6 @@
 package server
 
 import (
-	"fmt"
 	"io/fs"
 	"log/slog"
 	"net/http"
@@ -38,14 +37,3 @@ func registerStatic(mux *http.ServeMux) {
 		panic(err)
 	}
 }
-
-// cacheMiddleware adds Cache-Control headers to the response.
-func cacheMiddleware(maxAge time.Duration) func(next http.Handler) http.Handler {
-	return func(next http.Handler) http.Handler {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			w.Header().Set("Cache-Control", fmt.Sprintf("public, max-age=%.0f", maxAge.Seconds()))
-			w.Header().Set("Vary", "HX-Request,Accept-Language,Accept-Encoding")
-			next.ServeHTTP(w, r)
-		})
-	}
-}