Rails API validation errors

Untranslated validation errors with all meta data for APIs behind Javascript frontends

The easiest way to install Rails::API::ValidationErrors is to add it to your Gemfile:

gem "rails_api_validation_errors"

Then, install it on the command line:

$ bundle install

Include Rails::API::HashValidationErrors in your API's base controller. This makes sure that Rails will not translate error messages, but returns a hash per attribute and error including the error key and meta information.

class API::BaseController < ApplicationController
  include Rails::API::HashValidationErrors
end

To use the new error messages simply return the model's errors in JSON or XML in your controllers:

class API::PeopleController < API::BaseController

  def create
    @person = Person.new(person_params)

    if @person.valid?
      render :json => @person
    else
      render :json => { :errors => @person.errors }
    end
  end

end

This will result in the following JSON response in case of validation errors:

{
  "errors": {
    "name": [
      {
        "message": "blank",
        "meta":{}
      }
    ]
  }
}