Rails How to localize attributes from a form object

Question

I have already done some research but didn't managed to find how to localize the attributes for my form object.

Here is the relevant part of my form object model:

class Pledge
  include ActiveModel::Validations
  include ActiveModel::Conversion
  include ActiveAttr::Attributes
  extend ActiveModel::Naming

  attribute :pledge_amount
  attribute :reward_id
  attribute :message

  validates :message, presence: true, length: { maximum: 140 }
  validates :reward_id, presence: true
  validates :pledge_amount, presence: true

  ...
end

And my locale file, pledges/en.yml:

en:
  activerecord:
    models:
      pledge: "Pledge"
    attributes:
      pledge:
        pledge_amount: "Pledge Amount"
        reward_id: "Reward"
        message: "Message"
  helpers:
    submit:
      pledge:
        create: "Next Step"
    label:
      pledge:
        pledge_amount: "Enter your pledge amount"
        reward_id: "Select your reward"
        message: "Write a Support Message"

With this setup I managed to localize successfully the labels on the form, heres a part of the form code:

<%= form_for @pledge do |f|  %>
  <% if @pledge.errors.any? %>
    <div id="error_explanation">
      <h2><%= t :not_saved, count: @pledge.errors.count, model: t(:pledge) %></h2>
      <ul>
        <% @pledge.errors.full_messages.each do |msg| %>
          <li><%= msg %></li>
        <% end %>
      </ul>
    </div>
  <% end %>
  ...
  <%= f.label :pledge_amount %>
  <%= f.text_field :pledge_amount %>
  ...
  <%= f.submit class: "btn btn-lg btn-primary" %>
<% end %>

This renders the :pledge_amount label like: "Enter your pledge amount" in English, and the :submit button as "Next Step", great.

The problem happens when validations fail and I render the form with errors with the code I have under the tag, witch gives me the errors existent in the model but with blank attribute names, like this:

one error prohibited this Pledge from being saved:
 - can't be blank

When it was supposed to render:

one error prohibited this Pledge from being saved:
 - Pledge Amount can't be blank

If you are curious about this message in particular here's the code for that, shortened:

errors/en.yml

en:
  not_saved:
    one: "one error prohibited this %{model} from being saved:"
    other: "%{count} errors prohibited this %{model} from being saved:"
  errors:
    format: "%{message}"
  activerecord:
    errors:
      messages:
        blank: "%{attribute} can't be blank"

This works for all of my other models, but for this one for some reason it doesn't work, I think I'm using the wrong key on my pledges/en.yml file, as my Pledge model doesn't inherit from ActiveRecord...

Someone know the proper key to achieve this?

Answer 1

Put the translations on activemodel instead of activerecord in your yaml:

en:
  activemodel:
    models:
      pledge: "Pledge"
    attributes:
      pledge:
        pledge_amount: "Pledge Amount"
        reward_id: "Reward"
        message: "Message"

I dug this answer up from comments in an old RailsCast. See comment from Greg Yardley.

Answer 2

I managed to partially resolve this by adding custom messages on each validation I have in my form object, like this:

validates :pledge_amount, :presence => { :message => I18n.t(:blank_pledge_amount) }

And my en.yml file

blank_pledge_amount: "Please insert a pledge amount"

This way it works fine, but I would still like to know a better solution if someone has a better one. I hope this helps others with the same problem.

In order to validate the presence and the length of the message attribute, both with their messages I did like this:

validates_presence_of :message, :message => I18n.t(:blank_message)
validates_length_of :message, :maximum => 140, message: I18n.t(:message_too_long)