如何在Ruby on Rails中使用Rake Task设置两个外键？

Question

I have a rake task to create a number of invoices in my Rails application:

def make_invoices
  Project.all.each do |project|
    i = project.invoices.create!( :number     => random_number,
                                  :date       => random_date,
                                  :recipient  => random_recipient,
                                  :user_id    => project.person.user.id)        
    i.created_at = random_time
    i.save
  end
end

This line causes the rake task to fail, however:

:user_id => project.person.user.id

And I get the following error:

Can't mass-assign protected attributes: user_id

I know why this happens.

But I need to run this rake task and I wonder if there's any way to force mass-assign or something?

Each invoice's project_id is set automatically by the invoices.create! method. But what if I need to set a user_id as well?

Thanks for any help.

Answer 1

You need to do it outside of the call to create and change it to build :

def make_invoices
  Project.all.each do |project|
    i = project.invoices.build( :number     => random_number,
                                  :date       => random_date,
                                  :recipient  => random_recipient)   

    i.user_id = project.person.user.id
    i.save!

    i.created_at = random_time
    i.save
  end
end

Answer 2

(Possible duplicate of "Is there a way to bypass mass assignment protection?" )

It seems that assign_attributes can do that:

user = User.new
user.assign_attributes({ :name => 'Josh', :is_admin => true }, :without_protection => true)
user.name       # => "Josh"
user.is_admin?  # => true