Customizing Model Attributes

This guide covers how to add editable attributes to models in Solidus. We will cover an example of adding a new attribute to the Spree:Taxon model to allow for an additional text area.

• Adding attribute columns to the database
• Adding attribute fields to the admin panel
• Allowing custom attributes to be saved

Adding Columns to the Database

Columns can be added to Solidus database tables using standard Rails migrations standard Rails migrations .

If you wanted to add a more_information attribute, you could run the following command:

    
      rails generate migration AddMoreInformationToTaxons

    
  

This would create a migration file starting with a timestamp db/migrate/20190925192026_add_more_information_to_taxons.rb. Then update the file with the following contents to add a new text type column more_information to the table:

    
      class AddMoreInformationToTaxons < ActiveRecord::Migration[5.2]
  def change
    add_column :spree_taxons, :more_information, :text
  end
end

    
  

After you are done editing your migration run the following command to add the column to the database:

    
      rails db:migrate

    
  

Adding Fields to the Admin Panel

We have a complete guide on customizing the admin panel , but will go over it here briefly for our example. While that guide covers template replacement and using the Deface gem, we'll just cover the Deface approach. This allows changing parts of the views without overriding them entirely.

To add a new form field for a custom attribute to the taxon form, we would want to extend app/views/spree/admin/taxons/_form.html.erb from the Solidus backend. We can do that with Deface by creating a file app/overrides/spree/admin/taxons/_form/add_fields.html.erb.deface.

Below is an example of adding a new field to this form for a more_information field.

    
      <!-- insert_bottom '[data-hook=admin_inside_taxon_form]' -->
<div class="col-10">
  <%= f.field_container :more_information do %>
    <%= f.label :more_information %><br />
    <%= f.text_area :more_information, class: 'fullwidth', rows: 6 %>
  <% end %>
</div>

    
  

Allowing Custom Attributes to be Saved

If you try to submit the form with the new attribute field, you may notice it will not save to the database. This is due to many models having a list of permitted attributes. Models with a defined list of permitted attributes are defined in https://github.com/solidusio/solidus/blob/master/core/lib/spree/permitted_attributes.rb.

To extend the list for a model, we can add the following line to an initializer, for example in config/initializers/spree.rb:

    
      Spree::PermittedAttributes.taxon_attributes << [:more_information]

    
  

This tells Solidus that it's okay to accept values being saved to your custom attributes. If you were going to do this for multiple attributes, you can comma separate them.

After this has been added, you will need to reboot your Rails server. Now you can use the form in the admin panel to manage your custom attribute.