show expected message after add member error

app/controllers/groups/members_controller.rb

@@ -38,14 +38,14 @@ class Groups::MembersController < Groups::BaseController
   end
 
   def add
-    if params['user_id'].present?
-      @user = User.find_by_uname(params['user_id'])
-      if parent.add_member(@user, params[:role])
+    @user = User.find_by_uname(params[:user_id])
+    if !@user
+      flash[:error] = t("flash.collaborators.wrong_user", :uname => params[:user_id])
+    elsif parent.add_member(@user, params[:role])
       flash[:notice] = t("flash.members.successfully_added")
     else
       flash[:error] = t("flash.members.error_in_adding")
     end
-    end
     redirect_to group_members_path(parent)
   end
 end

app/controllers/platforms/platforms_controller.rb

@@ -96,13 +96,14 @@ class Platforms::PlatformsController < Platforms::BaseController
   end
 
   def add_member
-    if member = User.where(:id => params[:member_id]).first
-      if @platform.add_member(member)
+    member = User.where(:id => params[:member_id]).first
+    if !member
+      flash[:error] = t("flash.collaborators.wrong_user", :uname => params[:member_id])
+    elsif @platform.add_member(member)
       flash[:notice] = t('flash.platform.members.successfully_added', :name => member.uname)
     else
       flash[:error] = t('flash.platform.members.error_in_adding', :name => member.uname)
     end
-    end
     redirect_to members_platform_url(@platform)
   end
 

config/locales/en.yml

@@ -148,6 +148,7 @@ en:
       group_already_added: Group already added
       successfully_added: Member %s successfully added
       error_in_adding: Member %s adding error
+      wrong_user: User with nickname '%{uname}' not found!
 
     blob:
       successfully_updated: File '%{name}' successfully updated

config/locales/ru.yml

@@ -148,6 +148,7 @@ ru:
       group_already_added: Группа уже добавлена
       successfully_added: Участник %s успешно добавлен
       error_in_adding: Ошибка при добавлении участника %s
+      wrong_user: Пользователь с ником '%{uname}' не найден.
 
     blob:
       successfully_updated: Файл '%{name}' успешно обновлен