无法使用带有Strong_parameters和嵌套属性的POST更新或创建记录

Question

当我从表单中过帐时，我无法弄清楚为什么我的数据库记录没有得到更新或创建了新记录。

我能够手动填充数据库并创建关系：

contact = Contact.first
command = Command.find(3)
contact.host_notification_commands << command

而且我还可以在我的表单中加载此数据信息。 我不知道如何更新或添加新记录。 到目前为止，我尝试过的一切都失败了。

我有3个模型Command ， Contact和Joined CommandsContact 。 commands_contacts联接表具有一个额外的属性:notification_type ，可以将其设置为主机或服务 ，并且我的Contact模型设置了2个额外的关系，我可以访问:host_notification_commands和:service_notification_commands 。 这使我能够执行诸如Contact.fist.host_notification_commands或Contact.find(3).service_notification_commands.

似乎没有UPDATE或INSERT查询从控制器触发，当我执行正确的POST时，我不知道如何调试它。

楷模

class Command < ActiveRecord::Base

  has_many :commands_contacts
  has_many :contacts, :through => :commands_contacts

end

class Contact < ActiveRecord::Base

    has_many :commands_contacts
    has_many :commands, :through => :commands_contacts

    has_many :host_notification_commands, -> { where commands_contacts: { :notification_type => 'host' } },
            :through => :commands_contacts,
            :class_name => 'Command', 
            :source => :command

    has_many :service_notification_commands, -> { where commands_contacts: { notification_type: 'service' } },
            :through => :commands_contacts,
            :class_name => 'Command', 
            :source => :command

    accepts_nested_attributes_for :commands, :host_notification_commands, :service_notification_commands

end

class CommandsContact < ActiveRecord::Base

    belongs_to :command
    belongs_to :contact

    accepts_nested_attributes_for :command

end

在此之后，一切都崩溃了。

控制者

由于我正在使用accepts_nested_attributes_for ，因此我必须将_attributes附加到嵌套对象的名称- :host_notification_commands和:service_notification_commands 。 我将更改表单以这种方式提交，但是出于示例目的，简单的重新分配有效。

def update
    contact = Contact.find_by_id(params[:id])
    contact.update(safe_params)
end    

private
def safe_params

    params[:contact][:host_notification_commands_attributes] = params[:contact][:host_notification_commands]
    params[:contact][:service_notification_commands_attributes] = params[:contact][:service_notification_commands]

    params.require(:contact)
        .permit(:contact_name, :host_notification_commands_attributes => [:id, :command_name, :command_line, :command_description],
                :service_notification_commands_attributes => [:id, :command_name, :command_line, :command_description])
end

更新现有记录结果：

#<ActiveRecord::RecordNotFound: Couldn't find Command with ID=2 for Contact with ID=1>

当然不存在！ 我正在尝试建立这种关系！

添加一个新的，我得到：

#<ActiveRecord::RecordNotFound: Couldn't find Command with ID=1 for Contact with ID=>

完全正确。 用户甚至还没有创建，并且还没有通过命令建立关系，为什么Rails试图找到它？

我也没有在Rails控制台中看到任何更新或插入查询，因此我想它甚至没有达到这一点...

D, [2015-01-20T18:01:30.336669 #95542] DEBUG -- :    (0.1ms)  BEGIN
D, [2015-01-20T18:01:30.338971 #95542] DEBUG -- :   Command Load (0.3ms)  SELECT `commands`.* FROM `commands` INNER JOIN `commands_contacts` ON `commands`.`id` = `commands_contacts`.`command_id` WHERE `commands_contacts`.`contact_id` = 1 AND `commands_contacts`.`notification_type` = 'host' AND `commands`.`id` IN (1, 3)
D, [2015-01-20T18:01:30.340555 #95542] DEBUG -- :   Command Load (0.2ms)  SELECT `commands`.* FROM `commands` INNER JOIN `commands_contacts` ON `commands`.`id` = `commands_contacts`.`command_id` WHERE `commands_contacts`.`contact_id` = 1 AND `commands_contacts`.`notification_type` = 'service' AND `commands`.`id` IN (4, 2)
D, [2015-01-20T18:01:30.341501 #95542] DEBUG -- :    (0.1ms)  ROLLBACK
#<ActiveRecord::RecordNotFound: Couldn't find Command with ID=2 for Contact with ID=1>
Completed 200 OK in 11ms (Views: 0.4ms | ActiveRecord: 0.9ms)

我在这里想念什么？

编辑：我想我可以放弃使用strong_parameters的想法，解析所有POST参数，然后手动填充数据库，但是那不是Rails-y。

编辑2：包括发布到控制器的参数。

数据以params[:contact]形式输入

{
                     "contact_name" => "joe-user",
       "host_notification_commands" => [
        [0] {
                             "id" => 1,
                   "command_name" => "host-notify-by-email",
                   "command_line" => "/usr/local/bin/host-notify",
            "command_description" => "Host Alert",
                     "created_at" => "2015-01-19T17:24:12.000Z",
                     "updated_at" => "2015-01-21T03:29:03.000Z"
        },
        [1] {
                             "id" => 2,
                   "command_name" => "host-notify-by-pager",
                   "command_line" => "/usr/local/bin/host-notify-pager",
            "command_description" => "Host Alert by Pager",
                     "created_at" => "2015-01-19T17:24:33.000Z",
                     "updated_at" => "2015-01-19T17:24:33.000Z"
        }
    ],
    "service_notification_commands" => [
        [0] {
                             "id" => 4,
                   "command_name" => "service-notify-by-email",
                   "command_line" => "/usr/local/bin/service-notify",
            "command_description" => "Service Alert",
                     "created_at" => "2015-01-19T17:24:44.000Z",
                     "updated_at" => "2015-01-19T17:24:44.000Z"
        }
    ]
}

经过strong_parameters之后，它变成了：

本质上是一样的，只是剥离了created_at和updated_at并将_attributes附加到属性名称之后，因此它与accept_nested_attributes_for一起accept_nested_attributes_for

{
                                "contact_name" => "joe-user",
       "host_notification_commands_attributes" => [
        [0] {
                             "id" => 1,
                   "command_name" => "host-notify-by-email",
                   "command_line" => "/usr/local/bin/host-notify",
            "command_description" => "Host Alert"
        },
        [1] {
                             "id" => 2,
                   "command_name" => "host-notify-by-pager",
                   "command_line" => "/usr/local/bin/host-notify-pager",
            "command_description" => "Host Alert by Pager"
        }
    ],
    "service_notification_commands_attributes" => [
        [0] {
                             "id" => 4,
                   "command_name" => "service-notify-by-email",
                   "command_line" => "/usr/local/bin/service-notify",
            "command_description" => "Service Alert"
        }
    ]
}

编辑＃3：我已启用MySQL查询日志记录，但我根本看不到执行UPDATE / INSERT查询。 我如何调试为什么contact.update(safe_params)没有做任何事情？

编辑＃4：作为没有AngularJS或POST的简单测试，我做了一个简单的rake任务，该任务定义了JSON对象并尝试更新db。 我遇到了同样的问题，因此我非常确信该问题在我的模型中某处...但是在哪里？

请看看这个要点https://gist.github.com/pruchai/6afe74b170da2a3d307f

Answer 1

构建表单并使用nested_fields_for表单结构时，构建正确。 因此，理想情况下，您将首先尝试以“老式方式”执行此操作，然后检查推送到服务器的内容并进行模拟。

因此，通常我不会手动执行此操作，但我会维护一个gem来处理嵌套表单（茧），因此，如果我没有记错的话， accepts_nested_attributes起作用，参数必须如下所示：

{
    "contact_name" => "joe-user",
    "host_notification_commands_attributes" => {
      "0" => {
        "id" => 1,
        "command_name" => "host-notify-by-email",
        "command_line" => "/usr/local/bin/host-notify",
        "command_description" => "Host Alert"
      },
      "1" => {
        "id" => 2,
        "command_name" => "host-notify-by-pager",
        "command_line" => "/usr/local/bin/host-notify-pager",
        "command_description" => "Host Alert by Pager"
      }
    },
    "service_notification_commands_attributes" => {
      "0" => {
        "id" => 4,
        "command_name" => "service-notify-by-email",
        "command_line" => "/usr/local/bin/service-notify",
        "command_description" => "Service Alert"
      }, 
      "12342233444444" => {
        "command_name" => "service-notify-by-email",
        "command_line" => "/usr/local/bin/service-notify",
        "command_description" => "Service Alert"
      }
    }
  }

因此， .._attributes不应包含数组，而应包含哈希。 关键在于（现有）数组中的位置，我认为。 在茧中，我用从当前时间得出的一些大数字填充此虚拟索引 。 我假设此顺序应与该关系的默认顺序相对应。 但是，如果您将“ id”字段交给您，那么Rails也可能会使用它。 不确定。 要销毁现有元素，您必须设置_destroy属性（并在强参数中也允许它）。

恕我直言，新项目的id应该为空，否则Rails会假定该项目存在（因为通常不会在客户端生成ID）。