Rails 4强大的参数，没有必需的参数

I'm using Rails 4 and I don't know what is the best way to use strong parameters without required parameters. So, that's what I did:

我正在使用Rails 4，我不知道在没有必要参数的情况下使用强参数的最佳方式是什么。我就是这么做的:

def create
device = Device.new(device_params)
.................
end

private

def device_params
  if params[:device]
    params.require(:device).permit(:notification_token)
  else
    {}
  end
end

My device model does not validate presence of anything. I know I could do something like that too:

我的设备模型不验证任何东西的存在。我知道我也可以这么做:

device = Device.new
device.notification_token = params[:device][:notification_token] if params[:device] && params[:device][:notification_token]

Is there any conventions or the right way to do that?

有什么惯例或者正确的方法吗?

1 个解决方案

#1

You can use fetch instead of require.

您可以使用fetch而不是require。

def device_params
   params.fetch(:device, {}).permit(:notification_token)
end

Above will return empty hash when device is not present in params

当设备不在params中时，上面将返回空散列

Documentation here.

这里的文档。

#1