Question

我有两个表（节点和代理）。 nodes属于agents。我有一个将Rails项目拉入其中的脚本，我试图从ActiveRecord中提取值。我假设我要问的是它应该在控制器中查看还是在cli脚本中查看 - 或者 - 。所以，我的剧本看起来如此：

#!/usr/bin/env ruby

require '/Users/hseritt/devel/rails_projects/monitor_app/config/environment'

banner = "Banner running..."
script_dir = '/devel/rails_projects/monitor_app/monitor/bin'

class Runner

attr_accessor :banner, :agents, :agent_module, :nodes

def initialize(banner, script_dir)
    @banner = banner
    @agents = Agent.all
    @nodes = Node.all
    @script_dir = script_dir
end

def run
    puts @banner
    @agents.each do |agent|
        if agent.active?
            agent_module = '%s/%s' % [@script_dir, agent.name]
            require agent_module

            @nodes.each do |node|
                if node.agent == agent
                    puts node.name
                end
            end
                            #
            # HERE IS THE ISSUE:
            # ns = Node.find_by_agent_id(agent.id)
            # ns.each do |node|
            #   puts node.name
            # end
            # 
            # yields this error:
            #`method_missing': undefined method `each' for #<Node:0x007fe4dc4beba0> (NoMethodError)
            # I would think `ns` here would be itterable but it doesn't seem that way.
        end
    end
end
end

if $0 == __FILE__
    runner = Runner.new(banner, script_dir)
    runner.run  
end

所以，这是在run方法中。没有注释掉的块当然这不是一个好的解决方案，因为每次遍历代理时，您每次都必须遍历节点。被注释掉的块对我来说似乎合乎逻辑但却引发了错误。我觉得我可能在谷歌搜索正确的东西。我在这里缺少什么？

Answer 1

Node.find_all_by_agent_id

如果你不使用“all”，它只需要第一个元素

Ruby on Rails：在引用上进行查找

1 个答案: