Play with session cache in memory

Author: IgorPolyakov

internal/app/handlers/interface.go

@@ -4,6 +4,7 @@ import (
 	"ctf01d/internal/app/server"
 	"database/sql"
 	"net/http"
+	"sync"
 
 	openapi_types "github.com/oapi-codegen/runtime/types"
 )
@@ -12,7 +13,6 @@ type Handlers struct {
 	DB *sql.DB
 }
 
-// ServerInterfaceWrapper wraps Handlers to conform to the generated interface
 type ServerInterfaceWrapper struct {
 	handlers *Handlers
 }
@@ -21,6 +21,26 @@ func NewServerInterfaceWrapper(handlers *Handlers) *ServerInterfaceWrapper {
 	return &ServerInterfaceWrapper{handlers: handlers}
 }
 
+type SessionCache struct {
+	cache sync.Map
+}
+
+func NewSessionCache() *SessionCache {
+	return &SessionCache{}
+}
+
+type SessionServerInterfaceWrapper struct {
+	handlers     *Handlers
+	sessionCache *SessionCache
+}
+
+func NewSessionServerInterfaceWrapper(handlers *Handlers) *SessionServerInterfaceWrapper {
+	return &SessionServerInterfaceWrapper{
+		handlers:     handlers,
+		sessionCache: NewSessionCache(),
+	}
+}
+
 func (siw *ServerInterfaceWrapper) ListGames(w http.ResponseWriter, r *http.Request) {
 	siw.handlers.ListGames(w, r)
 }
@@ -49,7 +69,7 @@ func (siw *ServerInterfaceWrapper) PostApiV1AuthSignOut(w http.ResponseWriter, r
 	siw.handlers.PostApiV1AuthSignOut(w, r)
 }
 
-func (siw *ServerInterfaceWrapper) ValidateSession(w http.ResponseWriter, r *http.Request) {
+func (siw *SessionServerInterfaceWrapper) ValidateSession(w http.ResponseWriter, r *http.Request) {
 	siw.handlers.ValidateSession(w, r)
 }
 

internal/app/handlers/sessions.go

@@ -10,9 +10,31 @@ import (
 	api_helpers "ctf01d/internal/app/utils"
 	"ctf01d/internal/app/view"
 
+	"github.com/google/uuid"
 	openapi_types "github.com/oapi-codegen/runtime/types"
 )
 
+type SessionHandler struct {
+	*Handlers
+	SessionCache *SessionCache
+}
+
+func (sc *SessionCache) GetSession(sessionID string) (openapi_types.UUID, bool) {
+	val, ok := sc.cache.Load(sessionID)
+	if !ok {
+		return uuid.Nil, false
+	}
+	return val.(openapi_types.UUID), true
+}
+
+func (sc *SessionCache) SetSession(sessionID string, userID uuid.UUID) {
+	sc.cache.Store(sessionID, userID)
+}
+
+func (sc *SessionCache) DeleteSession(sessionID string) {
+	sc.cache.Delete(sessionID)
+}
+
 func (h *Handlers) PostApiV1AuthSignIn(w http.ResponseWriter, r *http.Request) {
 	var req server.PostApiV1AuthSignInJSONBody
 	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
@@ -72,13 +94,20 @@ func (h *Handlers) PostApiV1AuthSignOut(w http.ResponseWriter, r *http.Request)
 	api_helpers.RespondWithJSON(w, http.StatusOK, map[string]string{"data": "User logout successful"})
 }
 
-func (h *Handlers) ValidateSession(w http.ResponseWriter, r *http.Request) {
+func (h *SessionHandler) ValidateSession(w http.ResponseWriter, r *http.Request) {
 	cookie, err := r.Cookie("session_id")
 	if err != nil {
 		slog.Warn(err.Error(), "handler", "ValidateSession")
 		api_helpers.RespondWithJSON(w, http.StatusUnauthorized, map[string]string{"error": "No session found"})
 		return
 	}
+
+	if userId, ok := h.SessionCache.GetSession(cookie.Value); ok {
+		slog.Debug("ValidateSession user.Id " + openapi_types.UUID(userId).String())
+		h.respondWithUserDetails(w, r, userId)
+		return
+	}
+
 	slog.Debug("cookie.Value, " + cookie.Value)
 	repo := repository.NewSessionRepository(h.DB)
 	var userId openapi_types.UUID
@@ -88,12 +117,17 @@ func (h *Handlers) ValidateSession(w http.ResponseWriter, r *http.Request) {
 		api_helpers.RespondWithJSON(w, http.StatusUnauthorized, map[string]string{"error": "No user or session found"})
 		return
 	}
+
+	h.SessionCache.SetSession(cookie.Value, userId)
 	slog.Debug("ValidateSession user.Id " + openapi_types.UUID(userId).String())
+	h.respondWithUserDetails(w, r, userId)
+}
 
+func (h *SessionHandler) respondWithUserDetails(w http.ResponseWriter, r *http.Request, userId openapi_types.UUID) {
 	userRepo := repository.NewUserRepository(h.DB)
 	user, err := userRepo.GetById(r.Context(), userId)
 	if err != nil {
-		slog.Warn(err.Error(), "handler", "ValidateSession")
+		slog.Warn(err.Error(), "handler", "respondWithUserDetails")
 		api_helpers.RespondWithJSON(w, http.StatusInternalServerError, map[string]string{"error": "Could not find user by user id"})
 		return
 	}