A model inside another model creation

rubyonrails-talk
1

I got a model relationships Country <- (hm) city <- (hm) Address

The table city has two fields (both required) integer :country_id string :name

When creating a city the user can type a country in a country field <%form_for @city do |f| %>   <%= f.label :country %>   <%= f.text_field :country %>   <%= f.label :country %>   <%= f.text_field :country %> <%end%>

Before creating i would like to find a country by its name, if the name wouldn't exist then a new country would be created and it's `id` (the new created ones) would be placed in country_id (so self.country_id = id) field of the new city. Then if it validated a new city would be saved to database.

I was trying to do this in the model but couldn't succeed. My general idea was to do it with a callback like before_create, but it failed.

Any ideas on this one?

2

I got a model relationships Country <- (hm) city <- (hm) Address

The table city has two fields (both required) integer :country_id string :name

When creating a city the user can type a country in a country field <%form_for @city do |f| %> <%= f.label :country %> <%= f.text_field :country %> <%= f.label :country %> <%= f.text_field :country %> <%end%>

Before creating i would like to find a country by its name, if the name wouldn't exist then a new country would be created and it's `id` (the new created ones) would be placed in country_id (so self.country_id = id) field of the new city. Then if it validated a new city would be saved to database.

I was trying to do this in the model but couldn't succeed. My general idea was to do it with a callback like before_create, but it failed.

Any ideas on this one?

Did you try before_validation_on_create?

3

I've tried that one and i didn't work.

i get a 'undefined method `new_record?' for "Palestinian Territory, Occupied":String'

the app trace

vendor/rails/activerecord/lib/active_record/associations.rb:903:in `belongs_to_before_save_for_country' vendor/rails/activesupport/lib/active_support/callbacks.rb:173:in `send' vendor/rails/activesupport/lib/active_support/callbacks.rb:173:in `evaluate_method' vendor/rails/activesupport/lib/active_support/callbacks.rb:161:in `call' vendor/rails/activesupport/lib/active_support/callbacks.rb:93:in `run' vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `each' vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `send' vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in `run' vendor/rails/activesupport/lib/active_support/callbacks.rb:272:in `run_callbacks' vendor/rails/activerecord/lib/active_record/callbacks.rb:298:in `callback' vendor/rails/activerecord/lib/active_record/callbacks.rb:206:in `create_or_update' vendor/rails/activerecord/lib/active_record/base.rb:2200:in `save_without_validation' vendor/rails/activerecord/lib/active_record/validations.rb:901:in `save_without_dirty' vendor/rails/activerecord/lib/active_record/dirty.rb:75:in `save_without_transactions' vendor/rails/activerecord/lib/active_record/transactions.rb:106:in `save' vendor/rails/activerecord/lib/active_record/connection_adapters/ abstract/database_statements.rb:66:in `transaction' vendor/rails/activerecord/lib/active_record/transactions.rb:79:in `transaction' vendor/rails/activerecord/lib/active_record/transactions.rb:98:in `transaction' vendor/rails/activerecord/lib/active_record/transactions.rb:106:in `save' vendor/rails/activerecord/lib/active_record/transactions.rb:118:in `rollback_active_record_state!' vendor/rails/activerecord/lib/active_record/transactions.rb:106:in `save' app/controllers/cities_controller.rb:39:in `create' app/controllers/cities_controller.rb:38:in `create' script\server:3

the City model

class City < ActiveRecord::Base   belongs_to :country

  validates_presence_of :name,:country   validates_uniqueness_of :name

  attr_accessor :country

#here sould be all the automation happening   def before_validation_on_create     self.country_id = 0   end end

4

Ok so I've figured out some thing There is a problem between the belongs_to :country and the attr_accessor :country

The names should be different I hope from now on it'll be a piece of cacke :wink: