Is there any way to halt saving of child before parent.
I am using accepts_nested_attributes_for with polymorphic association.
I used multiple options validates_presence_of :parent_id , validates_assoicated :parent but none are working.
For example, I do have a class
Class Person
include HasPhoneNumbers
..
end
module HasPhoneNumbers
def self.included(kclass)
kclass.has_many :phone_numbers, :as => :callable, :dependent => kclass == Person ? :destroy : :nullify
end
klass.accepts_nested_attributes_for :phone_numbers, :reject_if => lambda {|pn| pn.keys.any?{|k| k.to_sym != :id && pn[k].blank?} }
end
class PhoneNumber
belongs_to :callable, :polymorphic => true
end
So while saving person due to validation in person object, it was not saving. However, child(phone_number) was saving. So I need to restrict it to not save child(phone_number) before parent(person) saves.
I did try multiple options using validates_presence_of and validates_associated, but none are working for me.
#person = Person.new(params[:person])
ActiveRecord::Base.transaction do
person.save!
end
Wrapping your saves within a transaction should roll back the phone number save if the person fails validation.
Reference: ActiveRecord Transactions
Related
I have a polymorphic association (contact_details) in my Company model and I want to validate the parent model. Note: I am using accepts_nested_attributes_for in my parent model.
The basic rule:
the company must have at least one phone (phone is the kind of
contact_detail)
The problem:
accepts_nested_attributes_for call destroy for child objects AFTER
validation of the parent object
so the user are able to delete a phone. Of course, later, when the user will try to edit a company without a phone, he/she will get an error (The company must have at least one phone).
Company (Parent) model:
class Company < ActiveRecord::Base
PHONES_NUMBER_MIN = 1
attr_accessible :name, :contact_details_attributes, ...
has_many :contact_details, :as => :contactable, :dependent => :destroy
validate do |company|
check_phones_number
end
accepts_nested_attributes_for :contact_details, :allow_destroy => true, :reject_if => :all_blank
private
def phones_number_valid?
kind = ContactDetail::Kind.phone
phones = contact_details.select { |cd| cd.kind_id == kind.id }
phones.size >= PHONES_NUMBER_MIN
end
def check_phones_number
unless phones_number_valid?
errors.add(:base, :phones_too_short, :count => PHONES_NUMBER_MIN)
end
end
...
end
ContactDetail (Child) model:
class ContactDetail < ActiveRecord::Base
attr_accessible :kind_id, :kind_value_source
belongs_to :contactable, :polymorphic => true
belongs_to :kind
validates :kind_value_source, :presence => true, :length => {:maximum => 255}
...
end
Note: I simplified the original version, so objective was clear to you. Here is the gist with the code.
By using the reject_if option I am able to forbid the deletion of all the phones. It is probably the best option by now. But I want to hear your opinions.
I also found this question and tried to apply the answer, but it didn't helped a lot. The same problem, as I described above. I've drawn a flowchart so you can see the trace, as I see it.
How can I validate the parent model in such a case?
I would be grateful for any help.
From the question you referenced, you can get rid of the reject_if and modify the line in phones_number_valid?:
phones = contact_details.select { |cd| cd.kind_id == kind.id && !cd.marked_for_destruction? }
Whats wrong with this before_save-callback?
class Order < ActiveRecord::Base
has_many :line_items, :dependent => :destroy, :inverse_of => :order
accepts_nested_attributes_for :line_items
attr_accessible :line_items_attributes
before_save :mark_line_items_for_removal
def mark_line_items_for_removal
line_items.each do |line_item|
line_item.mark_for_destruction if line_item.quantity.to_f <= 0
end
end
end
When one of the line_items are marked for destruction, no line_item will be saved.
However the parent Order object does get saved.
Returning true does not make a difference...
about mark_for_destruction: http://apidock.com/rails/v3.1.0/ActiveRecord/AutosaveAssociation/mark_for_destruction
and why that instead of ":allow_destroy => true"? see here:
http://weblogs.manas.com.ar/spalladino/2010/03/15/deleting-children-with-accepts_nested_attributes_for-in-rails/
I believe you need to set the :autosave => true option for your has_many definition.
As stated, here:
http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#method-i-has_many
"If true, always save the associated objects or destroy them if marked for destruction, when saving the parent object. If false, never save or destroy the associated objects. By default, only save associated objects that are new records."
I've been using the association_collection method "other_ids" throughout my Rails app with no issues. However whenever I try to access it from within the model defining the association, Rails has no idea what I'm taking about. For example:
class Membership < ActiveRecord::Base
belongs_to :course, :touch => true
belongs_to :person, :touch => true
end
class Day < ActiveRecord::Base
belongs_to :course, :touch => true, :counter_cache => true
has_many :presents, :dependent => :delete_all
has_many :people, :through => :presents
before_destroy :clear_attendance
def clear_attendance
mems = Membership.where(:course_id => course.id, :person_id => person_ids)
mems.update_all(["attendance = attendance - ?", (1 / course.days.size.to_f)])
end
end
In this case, person_ids is always null. I've tried self.person_ids, people.ids, etc. All nothing. I have used day.person_ids elsewhere with no issues, so why can't I use it here?
I am using Ruby 1.9.1 and Rails 3.0.3. Here is the SQL call from my log:
[1m[36mAREL (0.0ms)[0m [1mUPDATE "memberships" SET attendance = attendance - 0.3333333333333333 WHERE ("memberships"."course_id" = 4) AND ("memberships"."person_id" IN (NULL))[0m
edit: added more code to clarify question
What you really want there is:
def a_method
self.people.all
end
But to answer your question, person_ids is the correct method, and it should return an empty array, not nil. I just tried an association like that out in 2.3.10. Maybe you can post some more of your code, rails version, etc.
Thanks for your help - I figured it out myself. The problem was the order of my callbacks. I was trying to call person_ids after the association had been deleted. Changing the order to this solved my issues.
class Day < ActiveRecord::Base
before_destroy :clear_attendance
belongs_to :course, :touch => true, :counter_cache => true
has_many :presents, :dependent => :delete_all
has_many :people, :through => :presents
I have a "user" model that "has_one" "membership" (active at a time). For auditing and data integrity reasons, I'd like it so that if the membership changes for a user, the old/current record (if existing) has an inactive/active flag swapped, and a new row is added for the new changed record. If there are no changes to the membership, I'd like to just ignore the update. I've tried implementing this with a "before_save" call-back on my user model, but have failed many times. Any help is greatly appreciated.
models:
class User < ActiveRecord::Base
has_one :membership, :dependent => :destroy
accepts_nested_attributes_for :membership, :allow_destroy => true
end
class Membership < ActiveRecord::Base
default_scope :conditions => {:active => 1}
belongs_to :user
end
I have what I think is a pretty elegant solution. Here's your user model:
class User < ActiveRecord::Base
has_one :membership, :dependent => :destroy
accepts_nested_attributes_for :membership
def update_membership_with_history attributes
self.membership.attributes = attributes
return true unless self.membership.changed?
self.membership.update_attribute(:active, false)
self.build_membership attributes
self.membership.save
end
end
This update_membership_with_history method allows us to handle changed or unchanged records. Next the membership model:
class Membership < ActiveRecord::Base
default_scope :conditions => {:active => true}
belongs_to :user
end
I changed this slightly, since active should be a boolean, not 1's and 0's. Update your migration to match. Now the update action, which is the only part of your scaffold that needs to change:
def update
#user = User.find(params[:id], :include => :membership)
membership_attributes = params[:user].delete(:membership_attributes)
if #user.update_attributes(params[:user]) && #user.update_membership_with_history(membership_attributes)
redirect_to users_path
else
render :action => :edit
end
end
We're simply parsing out the membership attributes (so you can still use fields_for in your view) and updating them separately, and only if needed.
Did you look at acts_as_versioned? In the before_save of the Membership you could create a new version of the User, which would be acts_as_versioned.
Got it working. While it's probably not the best implementation, all my tests are passing. Thanks for the input guys.
before_save :soft_delete_changed_membership
def soft_delete_changed_membership
if !membership.nil? then
if !membership.new_record? && membership.trial_expire_at_changed? then
Membership.update_all( "active = 0", [ "id = ?", self.membership.id ] )
trial_expire_at = self.membership.trial_expire_at
self.membership = nil
Membership.create!(
:user_id => self.id,
:trial_expire_at => trial_expire_at,
:active => true
)
self.reload
end
end
end
Why don't you just assume that the latest membership is the active one. This would save you a lot of headache.
class User < ActiveRecord::Base
has_many :memberships, :dependent => :destroy
end
class Membership < ActiveRecord::Base
nested_scope :active, :order => "created_at DESC", :limit => 1
belongs_to :user
def update(attributes)
self.class.create attributes if changed?
end
end
then you can use
#user.memberships.active
to get the active membership, and you can just update any membership to get a new membership, which will become the active membership because it is the latest.
Now I hava a problem,how can I make the callback#after_add receive a reference to the join model in a has_many :through association?
my code like this:
class Emergency
has_many :departments, :through => :eme_references, :after_add => Proc.new { |eme_reference| eme_reference.eme_flag = 1}
end
the attribute eme_flag is the model EmeReference's attribute! but in the block ,i get the eme_reference.class is Emergency.
I want to set the attribute eme_flag of the model EmeReference.
That is my question!
cheers!
Presumably Emergency also has_many :eme_references in order for the :through association to work?
In that case, you should be able to attach the callback there:
has_many :eme_references,
:after_add => Proc.new { |emergency, eme_ref| # code here }
The block accepts 2 parameters, the first will be the Emergency, the 2nd will be the EmeReference being added.
Perhaps a before_save callback on EmeReference can also do what you want in this instance?
I think what you want to do can't be done there.
You could create an after_create hook on departments (I'm assuming Emergency has_many eme_references has_many departments):
class Emergency
has_many :departments, :through => :eme_references
def flag!
eme_flag=1
save
end
end
class Department
after_create :check_emergency
# this allows you to call department.emergency. Will return nil if anything is nil
delegate :emergency, :to =>:eme_reference, :allow_nil => true
def check_emergency
self.emergency.flag! if self.emergency.present?
end
end