ruby-on-rails - Controller 操作引发错误

Question

我有一个 Controller 方法名称 process_message，它的目的是根据收到的消息将人们注册到特定的组。现在一切正常，除了它会一遍又一遍地将一个人注册到同一个组。我正在尝试添加一些快速代码来实现，以便他们只能注册到特定组一次。我以为我想通了，但是当我尝试执行我写的内容时出现错误。为了清楚起见，我将显示一些屏幕截图和一些代码。

这是我的 Controller 方法

def process_message
if message_params[:action] == 'subscribe'
  # result = SubscribeToGroup.call(message_params)
  # results.success? ? result.message : result.error
  message_params[:id] = "visitor" if message_params[:id] == "tulip" # hack for now
  @group = Group.find_by(name: message_params[:id])     
  if @group && @subscriber.groups << @group unless groups.include? (@group)                                                  ^
    @group.response
  else
    'You cannot subscribe to unknown group'
  end
elsif message_params[:action] == 'stop'
  # result = UnsubscribeToGroup.call(message_params)
  # results.success? ? result.message : result.error
  group_name = message_params[:id]
  @group = @subscriber.groups.find_by(name: group_name)
  @subscriber.groups.destroy(@group) if @group
  "You are now unsubscribed from #{group_name.upcase} notifications. Text '#{group_name.upcase}' to start receieving updates again."
else
  "Sorry, we don't recognize that command."
end
rescue Exception => e
"Something went wrong. Try again. #{e.message}"
end

您可以在第 7 行看到我有一些代码，我认为这些代码可以防止消息两次注册一个人，但它不起作用，这是我运行 Rspec 时的错误消息。

我希望我的问题很清楚，如果您需要更多代码，请告诉我。

Answer 1

我会避免将 if 和 unless 放在同一行

这是你想要做的吗？

# You may have meant to provide `@subscriber.groups` instead of `groups` here. I'm not sure from information provided.
unless groups.include?(@group) 
  @subscriber.groups << @group 
end

if @group && @subscriber.groups.present?
# ...