chore: cache avatars in memory

routes/api/avatar.go

@@ -3,16 +3,26 @@ package api
 import (
 	"codeberg.org/Codeberg/avatars"
 	"github.com/gorilla/mux"
+	lru "github.com/hashicorp/golang-lru"
 	conf "github.com/muety/wakapi/config"
 	"net/http"
 )
 
 type AvatarHandler struct {
 	config *conf.Config
+	cache  *lru.Cache
 }
 
 func NewAvatarHandler() *AvatarHandler {
-	return &AvatarHandler{config: conf.Get()}
+	cache, err := lru.New(1 * 1000 * 64) // assuming an avatar is 1 kb, allocate up to 64 mb of memory for avatars cache
+	if err != nil {
+		panic(err)
+	}
+
+	return &AvatarHandler{
+		config: conf.Get(),
+		cache:  cache,
+	}
 }
 
 func (h *AvatarHandler) RegisterRoutes(router *mux.Router) {
@@ -21,15 +31,15 @@ func (h *AvatarHandler) RegisterRoutes(router *mux.Router) {
 }
 
 func (h *AvatarHandler) Get(w http.ResponseWriter, r *http.Request) {
-	vars := mux.Vars(r)
+	hash := mux.Vars(r)["hash"]
 
-	if vars["hash"] == "" {
-		w.WriteHeader(http.StatusNotFound)
-		w.Write([]byte{})
-		return
+	if !h.cache.Contains(hash) {
+		h.cache.Add(hash, avatars.MakeMaleAvatar(hash))
 	}
+	data, _ := h.cache.Get(hash)
 
 	w.Header().Set("Content-Type", "image/svg+xml")
+	w.Header().Set("Cache-Control", "max-age=2592000")
 	w.WriteHeader(http.StatusOK)
-	w.Write([]byte(avatars.MakeMaleAvatar(vars["hash"])))
+	w.Write([]byte(data.(string)))
 }