Rails Form Models

base_form.rb

# app/forms/base_form.rb
class BaseForm
  include ActiveModel::Validations
  include ActiveModel::Conversion
  extend ActiveModel::Naming

  def initialize(attributes = {})
    attributes.each do |name, value|
      send("#{name}=", value)
    end
  end

  def persisted?
    false
  end
end

new.html.erb

<%= form_for @signup, url: signup_path do |f| %>
    <% if @signup.errors.any? %>
        <div id="errorExplanation">
          <h2><%= pluralize(@signup.errors.count, 'error') %> prohibited your signup:</h2>
          <ul>
            <% @signup.errors.full_messages.each do |msg| %>
                <li><%= msg %></li>
            <% end %>
          </ul>
        </div>
    <% end %>
  ... you know how to do forms ...
<% end %>

signup.rb

# app/forms/signup.rb
class Signup < BaseForm
  attr_accessor :company_name,
    :subdomain,
    :email,
    :password,
    :password_confirmation,
    :first_name,
    :last_name

  validates :company_name, presence: true
  validates :subdomain, presence: true, subdomain: true
  validates :email, presence: true
  validates :first_name, :last_name, presence: true
  validates :password, presence: true, confirmation: true

  attr_reader :user, :company

  def save!
    return false unless valid?

    @company = Company.new(
      name: company_name,
      subdomain: subdomain
    )

    # bail out before creating schema so the user can correct any missing fields
    unless company.valid?
      company.errors.each do |attr, message|
        errors.add attr, message
      end

      return false
    end

    if company.save!
      # create a new schema for the company
      Apartment::Database.create(subdomain)
      Apartment::Database.switch(subdomain)

      @user = User.new(
        email: email,
        password: password,
        first_name: first_name,
        last_name: last_name
      )

      user.enabled = true
      user.build_profile # make a blank profile

      # create the admin user
      user.role = Role.where(name: 'System Administrator').first
      user.save!

      # load our post-create seeds into our schema
      load_post_create_seeds!

      user # return user to sign them in
    end
  end

private

  def load_post_create_seeds!
    silence_stream(STDOUT){ load_or_abort("#{Rails.root}/db/post-create-seeds.rb") }
  end

  def load_or_abort(file)
    if File.exists?(file)
      load(file)
    else
      abort %{#{file} doesn't exist yet}
    end
  end
end

signups_controller.rb

# app/controllers/signups_controller.rb
class SignupsController < ApplicationController
  respond_to :html

  def new
    @signup = Signup.new
    respond_with @signup
  end

  def create
    @signup = Signup.new(params[:signup])

    if user = @signup.save!
      sign_in user
    end

    respond_with @signup, location: root_url(subdomain: @signup.subdomain)
  end
end