使用Rails 2.3.2（目前不是很好的升级版本），使用ruby 1.8.7（2009-06-12 patchlevel 174）[universal-darwin10.0]。如果验证为:on => :update，则在对模型进行验证时尝试保存时会出现以下错误。如果我将验证更改为:on => :create并创建新记录，我看不到错误，如果没有验证，我没有问题保存。
Completed in 392ms (View: 10, DB: 296) | 200 OK [http://localhost/barfoos/update]
/!\ FAILSAFE /!\ Tue Sep 14 16:38:49 -0400 2010
Status: 500 Internal Server Error
User can't be referred
/path/to/project/vendor/rails/activerecord/lib/active_record/session_store.rb:67:in `dump'
/path/to/project/vendor/rails/activerecord/lib/active_record/session_store.rb:67:in `marshal'
/path/to/project/vendor/rails/activerecord/lib/active_record/session_store.rb:123:in `marshal_data!'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:178:in `send'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:178:in `evaluate_method'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:166:in `call'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:93:in `run'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `each'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `send'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `run'
/path/to/project/vendor/rails/activesupport/lib/active_support/callbacks.rb:276:in `run_callbacks'
/path/to/project/vendor/rails/activerecord/lib/active_record/callbacks.rb:344:in `callback'
/path/to/project/vendor/rails/activerecord/lib/active_record/callbacks.rb:249:in `create_or_update'
/path/to/project/vendor/rails/activerecord/lib/active_record/base.rb:2539:in `save_without_validation'
/path/to/project/vendor/rails/activerecord/lib/active_record/validations.rb:1009:in `save_without_dirty'
/path/to/project/vendor/rails/activerecord/lib/active_record/dirty.rb:79:in `save_without_transactions'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:229:in `send'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:229:in `with_transaction_returning_status'
/path/to/project/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in `transaction'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:182:in `transaction'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:228:in `with_transaction_returning_status'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:196:in `save_without_unsaved_flag'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:208:in `rollback_active_record_state!'
/path/to/project/vendor/rails/activerecord/lib/active_record/transactions.rb:196:in `save_without_unsaved_flag'
/path/to/project/vendor/plugins/active_scaffold/lib/extensions/unsaved_record.rb:15:in `save'
/path/to/project/vendor/rails/activerecord/lib/active_record/session_store.rb:300:in `set_session'
/path/to/project/vendor/rails/activerecord/lib/active_record/base.rb:1453:in `silence'
/path/to/project/vendor/rails/activerecord/lib/active_record/session_store.rb:297:in `set_session'
/path/to/project/vendor/rails/actionpack/lib/action_controller/session/abstract_store.rb:132:in `call'
/path/to/project/vendor/rails/activerecord/lib/active_record/query_cache.rb:29:in `call'
/path/to/project/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb:34:in `cache'
/path/to/project/vendor/rails/activerecord/lib/active_record/query_cache.rb:9:in `cache'
/path/to/project/vendor/rails/activerecord/lib/active_record/query_cache.rb:28:in `call'
/path/to/project/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb:361:in `call'
/path/to/project/vendor/rails/actionpack/lib/action_controller/reloader.rb:9:in `call'
/path/to/project/vendor/rails/actionpack/lib/action_controller/failsafe.rb:11:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/lock.rb:11:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/lock.rb:11:in `synchronize'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/lock.rb:11:in `call'
/path/to/project/vendor/rails/actionpack/lib/action_controller/dispatcher.rb:106:in `call'
/path/to/project/vendor/rails/railties/lib/rails/rack/static.rb:31:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/urlmap.rb:46:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/urlmap.rb:40:in `each'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/urlmap.rb:40:in `call'
/path/to/project/vendor/rails/railties/lib/rails/rack/log_tailer.rb:17:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/content_length.rb:13:in `call'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/handler/webrick.rb:50:in `service'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:162:in `start'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:95:in `start'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:92:in `each'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:92:in `start'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:23:in `start'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/webrick/server.rb:82:in `start'
/Library/Ruby/Gems/1.8/gems/rack-1.0.1/lib/rack/handler/webrick.rb:14:in `run'
/path/to/project/vendor/rails/railties/lib/commands/server.rb:111
/Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require'
script/server:3
该模型如下所示：
class Barfoo < ActiveRecord::Base
default_scope :conditions => {:scoping_model_id => ScopingModel.current_version.id}
belongs_to :scoping_model
# validate is false to keep from attempting to validate Foobar on Barfoo save, as Foobar can be saved, even if invalid, unlike Barfoo.
has_one :foobar, :validate => false
validates_presence_of :foobar_id, :on => :create, :message => "can't be blank"
validates_inclusion_of :accepted_an_agreement, :in => [true, false], :on => :update, :message => "please choose whether you agree or disagree"
validates_presence_of :some_option_string, :on => :update, :message => "before agreeing, you must specify the some string", :if => Proc.new { |detail| detail.accepted_an_agreement == true }
validates_presence_of :some_text, :on => :update, :message => "you must provide details if option is 'Other'", :if => Proc.new { |detail| detail.some_option_string == 'Other' }
end
我指定的这些字段的值无关紧要，并且在下面的评论中注明Shadwell，它似乎与会话相关。我们在ApplicationController中执行会话相关和用户相关的一件事可能会导致此问题，即使它在此之前从未出现过问题。 ApplicationController看起来像：
class ApplicationController < ActionController::Base
include ExceptionNotifiable
require 'something_that_defines_update_method_that_we_redefine_in_controller'
include Userstamp
ActionController::Base.session_options[:httponly] = true
ActionController::Base.session_options[:secure] = true
prepend_before_filter :user_setting_method
...
protected
def user_setting_method
session[:username] ||= optional_override_username
session[:username] = session[:username] # touch the session for timeout purposes
@user ||= User.find_by_username session[:username]
true
end
...
end
搜索没有提及/!\ FAILSAFE /!\与User can't be referred的关系。任何关于什么会导致这种情况的想法，是否存在可以解决这个问题的常见解决方案？
请注意，附加到此的foobar实例已保存，但在此特定情况下，foobar之前已保存很久，但未进行验证（未经验证即保存，这是正常的可能的状态，因为它是来自多页表单的数据，可以部分保存数据，用户可以返回并在以后更正完成。
答案 0 :(得分：1)
继续开发模型之后，我开始收到另一个错误：
/!\ FAILSAFE /!\ Fri Sep 17 14:53:50 -0400 2010
Status: 500 Internal Server Error
can't dump hash with default proc
我尝试在控制台中保存模型并且成功了，但看到了一些奇怪的事情。当我已经在模型上设置了有效的foobar_id时，它要求foobar有效（例如）。所以，我和一个团队成员讨论过这个问题，听说他已经读过有关试图验证相关对象id的问题。
我删除了：
validates_presence_of :foobar_id, :on => :create, :message => "can't be blank"
并且有效。
但是，另一位同事向我建议，我所遇到的问题可能与执行validates_presence_of :foobar_id有关，当我在控制器中尝试设置foobar时：
barfoo.foobar = foobar
而不是像foobar_id那样设置：
barfoor.foobar_id = foobar.id
我还注意到，在前一个示例中，它没有在数据库的相关行中设置foobar_id。
将其更改为在foobar_id上设置barfoo后，只要没有更新验证，它似乎会保存在创建和更新上。但是，如果我添加验证:on => :update的验证，则会失败。
答案 1 :(得分：0)
在activerecord/lib/active_record/session_store.rb
ActiveRecord::SessionStore::ClassMethods.module_eval do
def marshal(data)
# To prevent from Marshal dump error
begin
::Base64.encode64(Marshal.dump(data)) if data
rescue
# Checks for any ActiveRecord object in session variables and reloads it
data.each_pair do |key,obj|
if obj.is_a?(ActiveRecord::Base) || obj.is_a?(Array)
unless obj.is_a?(Array)
data[key] = obj.reload
next
end
data[key].collect do |it_obj|
if obj.is_a?(ActiveRecord::Base)
it_obj.reload
else
it_obj
end
end
end
end
::Base64.encode64(Marshal.dump(data)) if data
end
end
end
简单来说，它将重新加载会话变量
中存在的所有ActiveRecord对象