导轨的has_many：通过与环境和建筑协会 [英] Rails has_many :through with conditions and building associations

问题描述

我有建立一个协会是一个的has_many问题：通过与条件。我有这样的模式：

 类联系与LT; AR
  的has_many：group_contacts
  的has_many：组：通过=＆GT; ：group_contacts，：条件=＆GT; {：组=＆GT; {：公布=＆GT;真正}}
结束
 

问题，当我尝试从一个接触实例一组发生。通过上面的语法，我得到一个错误：

  contact.groups.build
=＆GT; ActiveRecord的:: UnknownAttributeError：未知属性：群体
 

但是，当我用下面的语法它的工作原理：

 的has_many：组：通过=＆GT; ：group_contacts，：条件=＆GT; ['groups.published =？'，真]

contact.groups.build
=＆GT; ＃＆LT;组ID：无，名：无，说明：无，created_at：无，的updated_at：无，发表：真＆gt;
 

我看到提及确切的问题在<一个href="http://stackoverflow.com/questions/1514880/how-can-i-create-new-records-with-has-many-through-and-honor-conditions">this问题。据说一张票将针对这个漏洞（早在pre型导轨3个版本）。我找不到然而，在什么轨3.0.x的。

我使用的是3.0.8。有没有其他人发现这个问题？

其它注意事项的：

我还发现，当我在建筑群体，其建筑的时候居然忽略了我的条件上的关联。我上面构建了出版的唯一原因=＆GT;真正的是因为它是默认的数据库。

这似乎是一个回归，可谁都验证这一点？

解决方案

 的has_many：组：通过=＆GT; ：group_contacts，：条件=＆GT; {：公布=＆GT;真正}
 

或

 的has_many：组：通过=＆GT; ：group_contacts，：条件=＆GT; {groups.published=＆GT;真正}
 

I'm having problems building an association that is a has_many :through with conditions. I have this model:

class Contact < AR
  has_many :group_contacts
  has_many :groups, :through => :group_contacts, :conditions => {:groups => {:published => true}}
end

problem happens when I try to instantiate a group from a contact. With the above syntax, I get an error:

contact.groups.build
=> ActiveRecord::UnknownAttributeError: unknown attribute: groups

But when I use the following syntax it works:

has_many :groups, :through => :group_contacts, :conditions => ['groups.published = ?', true]

contact.groups.build
=> #<Group id: nil, name: nil, description: nil, created_at: nil, updated_at: nil, published: true>

I see a reference to the exact problem in this question. It is said a ticket would be filed for this bug (back in pre- rails 3 versions). I can't find anything however on rails 3.0.x.

I'm using 3.0.8. Has anyone else found this issue?

Further Notes:

I've also found that when I'm building groups, it actually ignores my conditions on the association when building. The only reason my above build had published => true is because it's the default in the db.

This seems like a regression, can anyone else verify this?

解决方案

has_many :groups, :through => :group_contacts, :conditions => {:published => true}

or

has_many :groups, :through => :group_contacts, :conditions => {"groups.published" => true}

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