I believe what you are asking for can be achieved with ActiveSupport::Callbacks. Have a look at set_callback and skip_callback. In order to “force callbacks to get called even if you made no changes to the record”, you need to register the callback to some event e.g. save, validate etc.. set_callback :save, :before, :my_before_save_callback To skip … Read more
No need to surround the methods in array. Simply use: after_create :do_this, :and_then_this Bonus Information: If a before_* callback returns false, all the later callbacks and the associated action are cancelled. If an after_* callback returns false, all the later callbacks are cancelled. Callbacks are generally run in the order they are defined, with the … Read more
From the Guides first_or_create The first_or_create method checks whether first returns nil or not. If it does return nil, then create is called. This is very powerful when coupled with the where method. Let’s see an example. Suppose you want to find a client named ‘Andy’, and if there’s none, create one and additionally set … Read more
As with prior versions of Rails, you may use the following command to create the migration: rails g migration AddUserToUploads user:references Unlike prior versions of Rails, the migration looks like: class AddUserToUploads < ActiveRecord::Migration[5.0] def change add_reference :uploads, :user, foreign_key: true end end
You can do this simply with the add_column method in your migrations and set up the proper associations in your classes: class AddFields < ActiveRecord::Migration def change add_column :tickets, :image_1_id, :integer add_column :tickets, :image_2_id, :integer end end class Ticket < ActiveRecord::Base belongs_to :image_1, :class_name => “Image” belongs_to :image_2, :class_name => “Image” end class Image < … Read more
Rails doesn’t have the facility to pass the options for include query. But we can pass these params with the association declaration under the model. For your scenario, you need to create a new association with users model under the profile model, like below belongs_to :user_only_fetch_email, :select => “users.id, users.email”, :class_name => “User” I just … Read more
You’re looking for reflect_on_all_associations. So in short: Post.reflect_on_all_associations(:has_many) …will give an array (of object with attributes like name, etc) of all has_many associations.
Add in your gemfile: gem ‘validates_email_format_of’ and in your model: validates :email, email_format: { message: “doesn’t look like an email address” } Or if you don’t want use a gem, use regex: validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i
You can implement your own method in your model. Something like this def valid_attribute?(attribute_name) self.valid? self.errors[attribute_name].blank? end Or add it to ActiveRecord::Base
Update Rails 6.1 With the new Rails version this becomes simple, as described here: .where.missing(:children) For older versions see below. Rails 3 & 4 scope :without_children, includes(:children).where(:children => { :id => nil }) The big difference here is the joins becoming a includes: an include loads all the relations, if they exists, the join will … Read more