ruby – 使用ActiveResource保存时,“为数据分配器未定义”

我错过了什么？我正在尝试使用Active资源的休息服务,我有以下内容：

class User < ActiveResource::Base
  self.site = "http://localhost:3000/"
  self.element_name = "users"
  self.format = :json
end

user = User.new(
        :name => "Test",:email => "[e-mail]")

p user 
if user.save
  puts "success: #{user.uuid}"
else
  puts "error: #{user.errors.full_messages.to_sentence}"
end

并为用户输出以下内容：

#<User:0x1011a2d20 @prefix_options={},@attributes={"name"=>"Test","email"=>"[e-mail]"}>

而这个错误：

/Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1233:in `new': allocator undefined for Data (TypeError)
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1233:in `load'
from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1219:in `each'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1219:in `load'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1322:in `load_attributes_from_response'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1316:in `create_without_notifications'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1314:in `tap'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1314:in `create_without_notifications'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/observing.rb:11:in `create'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1117:in `save_without_validation'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/validations.rb:87:in `save_without_notifications'
    from /Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/observing.rb:11:in `save'
    from import_rest.rb:22

如果我用户为我的休息服务卷曲,那就像：

curl -v -X POST -H 'Content-Type: application/json' -d '{"name":"test curl","email":"[e-mail]"}' http://localhost:3000/users

回复：

{"email":"[e-mail]","name":"test curl","admin":false,"uuid":"afb8c98b-562a-4603-bbe4-f8f0816cef0d","creation_limit":5}

解决方法

有一个名为Data的内置类型,其目的是 rather mysterious.您似乎碰到了它：

$ruby -e 'Data.new'
-e:1:in `new': allocator undefined for Data (TypeError)
  from -e:1

问题是,它是如何实现的？最后一个堆栈框架将我们设置为here.因此,看起来数据在调用find_or_create_resource_for之后徘徊.代码分支here很可能：

$irb
>> class C
>>   end
=> nil
>> C.const_get('Data')
=> Data

这导致我怀疑你有一个属性或类似名称：数据或“数据”,即使你没有提到上面的一个.你呢？特别是,似乎我们有一个带有子哈希的JSON响应,其键是“数据”.

这是一个可以触发精心设计的输入错误的脚本,但不是来自您发布的响应：

$cat ./activeresource-oddity.rb
#!/usr/bin/env ruby

require 'rubygems'
gem 'activeresource','3.0.10'
require 'active_resource'

class User < ActiveResource::Base
  self.site = "http://localhost:3000/"
  self.element_name = "users"
  self.format = :json
end

USER = User.new :name => "Test",:email => "[e-mail]"

def simulate_load_attributes_from_response(response_body)
  puts "Loading #{response_body}.."
  USER.load User.format.decode(response_body)
end

OK = '{"email":"[e-mail]","creation_limit":5}'
BORKED = '{"data":{"email":"[e-mail]","creation_limit":5}}'

simulate_load_attributes_from_response OK
simulate_load_attributes_from_response BORKED

生产..

$./activeresource-oddity.rb 
Loading {"email":"[e-mail]","creation_limit":5}..
Loading {"data":{"email":"[e-mail]","creation_limit":5}}..
/opt/local/lib/ruby/gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1233:in `new': allocator undefined for Data (TypeError)
    from /opt/local/lib/ruby/gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1233:in `load'
    from /opt/local/lib/ruby/gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1219:in `each'
    from /opt/local/lib/ruby/gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb:1219:in `load'
    from ./activeresource-oddity.rb:17:in `simulate_load_attributes_from_response'
    from ./activeresource-oddity.rb:24

如果我是你,我会打开/Library/Ruby/Gems/1.8/gems/activeresource-3.0.10/lib/active_resource/base.rb,在1320行找到load_attributes_from_response并暂时更改

load(self.class.format.decode(response.body))

至

load(self.class.format.decode(response.body).tap { |decoded| puts "Decoded: #{decoded.inspect}" })

..并再次重现错误,看看你的json解码器真正出现了什么.