自定义错误处理和康康舞

我正在尝试实现自定义错误处理以及使用 CanCan。当用户到达不允许访问的区域时，会引发 CanCan::AccessDenied 错误，并且应将其发送到根 url。相反，“rescue_from Exception”捕获 CanCan::AccessDenied 并且用户收到 500 错误。我究竟做错了什么？

#application_controller.rb
rescue_from CanCan::AccessDenied do |exception|
  redirect_to main_app.root_url, :alert => exception.message
end

rescue_from Exception,
  :with => :render_error
rescue_from Mongoid::Errors::DocumentNotFound,
  :with => :render_not_found
rescue_from ActionController::RoutingError,
  :with => :render_not_found
rescue_from ActionController::UnknownController,
  :with => :render_not_found
rescue_from AbstractController::ActionNotFound,
  :with => :render_not_found


def render_not_found(exception)
  render :template => "/errors/404.html",
       :layout => 'errors.html',
       :status => 404
end

def render_error(exception)
  render :template => "/errors/500.html",
       :layout => 'errors.html',
       :status => 500
end

您是否尝试从异常/错误中重新排序rescue_，首先更通用，稍后更具体，例如

rescue_from StandardError,
  :with => :render_error
rescue_from Mongoid::Errors::DocumentNotFound,
  :with => :render_not_found
rescue_from ActionController::RoutingError,
  :with => :render_not_found
rescue_from ActionController::UnknownController,
  :with => :render_not_found
rescue_from AbstractController::ActionNotFound,
  :with => :render_not_found
rescue_from CanCan::AccessDenied do |exception|
  redirect_to main_app.root_url, :alert => exception.message
end

注意：您可能想用 StandardError 替换通用异常。