add user identification

api/api.go

@@ -36,6 +36,12 @@ func Start() {
 		panic("oh no")
 	})
 
+	r.Route("/whoami", func(r chi.Router) {
+		r.Use(SessionAuthMiddleware)
+		r.Use(LoginCtx)
+		r.Get("/", Whoami)
+	})
+
 	r.Route("/messages", func(r chi.Router) {
 		r.Use(SessionAuthMiddleware) // Protect with authentication
 

api/user.go

@@ -30,6 +30,38 @@ func UserCtx(next http.Handler) http.Handler {
 	})
 }
 
+func Whoami(w http.ResponseWriter, r *http.Request) {
+	user, ok := r.Context().Value(userKey{}).(*User)
+	if !ok {
+		w.Write([]byte("undefined"))
+		return
+	} else {
+		w.Write([]byte(user.Name))
+		return
+	}
+}
+
+func LoginCtx(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var user *User
+		var err error
+
+		if username := r.Context().Value(usernameKey).(string); username != "" {
+			user, err = dbGetUserByName(username)
+		} else {
+			render.Render(w, r, ErrNotFound)
+			return
+		}
+		if err != nil {
+			render.Render(w, r, ErrNotFound)
+			return
+		}
+
+		ctx := context.WithValue(r.Context(), userKey{}, user)
+		next.ServeHTTP(w, r.WithContext(ctx))
+	})
+}
+
 func GetUser(w http.ResponseWriter, r *http.Request) {
 	user, ok := r.Context().Value(userKey{}).(*User)
 	if !ok || user == nil {