From fca1030e1a776c3726bc9b79017d53d55755d59c Mon Sep 17 00:00:00 2001
From: schreifuchs <kontakt@schreifuchs.ch>
Date: Sat, 7 Mar 2026 20:26:53 +0100
Subject: [PATCH] feat: limit image request

---
 internal/components/images/controller.go | 7 +++++++
 internal/components/images/resorce.go    | 5 ++++-
 internal/server/routes.go                | 2 +-
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/internal/components/images/controller.go b/internal/components/images/controller.go
index 2a156dd..6304570 100644
--- a/internal/components/images/controller.go
+++ b/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
diff --git a/internal/components/images/resorce.go b/internal/components/images/resorce.go
index 98d36e8..91aaac2 100644
--- a/internal/components/images/resorce.go
+++ b/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),
 	}
 }
 
diff --git a/internal/server/routes.go b/internal/server/routes.go
index cef6d59..93d135c 100644
--- a/internal/server/routes.go
+++ b/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())))