Bring simple signup flow from the fizzy-saas gem

We skip the QB code and we fill external account ids automatically on creation with a sequence

See:
https://github.com/basecamp/fizzy-saas/pull/7

Gemfile.saas

@@ -6,6 +6,6 @@ git_source(:bc) { |repo| "https://github.com/basecamp/#{repo}" }
 
 gem "activeresource", require: "active_resource"
 gem "queenbee", bc: "queenbee-plugin"
-gem "fizzy-saas", bc: "fizzy-saas"
+gem "fizzy-saas", bc: "fizzy-saas", branch: "extract-signup"
 gem "rails_structured_logging", bc: "rails-structured-logging"
 

Gemfile.saas.lock

@@ -1,6 +1,7 @@
 GIT
   remote: https://github.com/basecamp/fizzy-saas
-  revision: 40f68d8604a1b410ba514f5793a93e9b11c00219
+  revision: 3b012b9ffa7c8fdc1e4b9f5aa7d866ed4108a8ff
+  branch: extract-signup
   specs:
     fizzy-saas (0.1.0)
       queenbee

app/controllers/application_controller.rb

@@ -4,7 +4,6 @@ class ApplicationController < ActionController::Base
   include CurrentRequest, CurrentTimezone, SetPlatform
   include RequestForgeryProtection
   include TurboFlash, ViewTransitions
-  include Saas
   include RoutingHeaders
 
   etag { "v1" }

app/controllers/concerns/saas.rb

@@ -1,11 +0,0 @@
-module Saas
-  extend ActiveSupport::Concern
-
-  included do
-    helper_method :signups_allowed?
-  end
-
-  def signups_allowed?
-    defined?(Signup) && defined?(saas)
-  end
-end

app/controllers/sessions_controller.rb

@@ -22,10 +22,8 @@ class SessionsController < ApplicationController
       magic_link = identity.send_magic_link
       flash[:magic_link_code] = magic_link&.code if Rails.env.development?
       redirect_to session_magic_link_path
-    elsif signups_allowed?
-      Signup.new(email_address: email_address).create_identity
-      session[:return_to_after_authenticating] = saas.new_signup_completion_path
-      redirect_to session_magic_link_path
+    elsif
+      process_new_signup
     end
   end
 
@@ -38,4 +36,10 @@ class SessionsController < ApplicationController
     def email_address
       params.expect(:email_address)
     end
+
+    def process_new_signup
+      Signup.new(email_address: email_address).create_identity
+      session[:return_to_after_authenticating] = new_signup_completion_path
+      redirect_to session_magic_link_path
+    end
 end

app/controllers/signup/completions_controller.rb

@@ -0,0 +1,24 @@
+class Signup::CompletionsController < ApplicationController
+  layout "public"
+
+  disallow_account_scope
+
+  def new
+    @signup = Signup.new(identity: Current.identity)
+  end
+
+  def create
+    @signup = Signup.new(signup_params)
+
+    if @signup.complete
+      redirect_to landing_url(script_name: @signup.account.slug)
+    else
+      render :new, status: :unprocessable_entity
+    end
+  end
+
+  private
+    def signup_params
+      params.expect(signup: %i[ full_name ]).with_defaults(identity: Current.identity)
+    end
+end

app/models/signup.rb

@@ -0,0 +1,100 @@
+class Signup
+  include ActiveModel::Model
+  include ActiveModel::Attributes
+  include ActiveModel::Validations
+
+  attr_accessor :full_name, :email_address, :identity
+  attr_reader :account, :user
+
+  with_options on: :completion do
+    validates_presence_of :full_name, :identity
+  end
+
+  def initialize(...)
+    super
+
+    @email_address = @identity.email_address if @identity
+  end
+
+  def create_identity
+    @identity = Identity.find_or_create_by!(email_address: email_address)
+    @identity.send_magic_link
+  end
+
+  def complete
+    if valid?(:completion)
+      begin
+        @tenant = create_tenant
+        create_account
+        true
+      rescue => error
+        destroy_account
+        handle_account_creation_error(error)
+
+        errors.add(:base, "Something went wrong, and we couldn't create your account. Please give it another try.")
+        Rails.error.report(error, severity: :error)
+        Rails.logger.error error
+        Rails.logger.error error.backtrace.join("\n")
+
+        false
+      end
+    else
+      false
+    end
+  end
+
+  private
+    # Override to customize the handling of external accounts associated to the account.
+    def create_tenant
+      nil
+    end
+
+    # Override to inject custom handling for account creation errors
+    def handle_account_creation_error(error)
+    end
+
+    def create_account
+      @account = Account.create_with_admin_user(
+        account: {
+          external_account_id: @tenant,
+          name: generate_account_name
+        },
+        owner: {
+          name: full_name,
+          identity: identity
+        }
+      )
+      @user = @account.users.find_by!(role: :admin)
+      @account.setup_customer_template
+    end
+
+    def generate_account_name
+      AccountNameGenerator.new(identity: identity, name: full_name).generate
+    end
+
+
+    def destroy_account
+      @account&.destroy!
+
+      @user = nil
+      @account = nil
+      @tenant = nil
+    end
+
+    def subscription_attributes
+      subscription = FreeV1Subscription
+
+      {}.tap do |attributes|
+        attributes[:name]  = subscription.to_param
+        attributes[:price] = subscription.price
+      end
+    end
+
+    def request_attributes
+      {}.tap do |attributes|
+        attributes[:remote_address] = Current.ip_address
+        attributes[:user_agent]     = Current.user_agent
+        attributes[:referrer]       = Current.referrer
+      end
+    end
+end

app/models/signup/account_name_generator.rb

@@ -0,0 +1,53 @@
+class Signup::AccountNameGenerator
+  SUFFIX = "Fizzy".freeze
+
+  attr_reader :identity, :name
+
+  def initialize(identity:, name:)
+    @identity = identity
+    @name = name
+  end
+
+  def generate
+    next_index = current_index + 1
+
+    if next_index == 1
+      "#{prefix} #{SUFFIX}"
+    else
+      "#{prefix} #{next_index.ordinalize} #{SUFFIX}"
+    end
+  end
+
+  private
+    def current_index
+      existing_indices.max || 0
+    end
+
+    def existing_indices
+      Current.without_account do
+        identity.accounts.filter_map do |account|
+          if account.name.match?(first_account_name_regex)
+            1
+          elsif match = account.name.match(nth_account_name_regex)
+            match[1].to_i
+          end
+        end
+      end
+    end
+
+    def first_account_name_regex
+      @first_account_name_regex ||= /\A#{prefix}\s+#{SUFFIX}\Z/i
+    end
+
+    def nth_account_name_regex
+      @nth_account_name_regex ||= /\A#{prefix}\s+(1st|2nd|3rd|\d+th)\s+#{SUFFIX}/i
+    end
+
+    def prefix
+      @prefix ||= "#{first_name}'s"
+    end
+
+    def first_name
+      name.strip.split(" ", 2).first
+    end
+end

app/views/sessions/menus/show.html.erb

@@ -24,13 +24,11 @@
       <p class="margin-none-block-start">You don’t have any Fizzy accounts.</p>
     <% end %>
 
-    <% if signups_allowed? %>
     <div class="margin-block-start">
-        <%= link_to saas.new_signup_completion_path, class: "btn btn--plain txt-link center txt-small", data: { turbo_prefetch: false } do %>
+      <%= link_to new_signup_completion_path, class: "btn btn--plain txt-link center txt-small", data: { turbo_prefetch: false } do %>
         <span>Sign up for a new Fizzy account</span>
       <% end %>
     </div>
-    <% end %>
   </div>
 <% end %>
 

app/views/signup/completions/new.html.erb

@@ -0,0 +1,30 @@
+<% @page_title = "Complete your sign-up" %>
+
+<div class="panel panel--centered flex flex-column gap-half <%= "shake" if flash[:alert] %>">
+  <h1 class="txt-x-large font-weight-black margin-block-end"><%= @page_title %></h1>
+
+  <%= form_with model: @signup, url: signup_completion_path, scope: "signup", class: "flex flex-column gap", data: { controller: "form" } do |form| %>
+    <%= form.text_field :full_name, class: "input txt-large", autocomplete: "name", placeholder: "Enter your full name…", autofocus: true, required: true %>
+
+    <p>You're one step away. Just enter your name to get your own Fizzy account.</p>
+
+    <% if @signup.errors.any? %>
+      <div class="margin-block-half">
+        <ul class="margin-block-none txt-negative txt-small">
+          <% @signup.errors.full_messages.each do |message| %>
+            <li><%= message %></li>
+          <% end %>
+        </ul>
+      </div>
+    <% end %>
+
+    <button type="submit" class="btn btn--link center" data-form-target="submit">
+      <span>Continue</span>
+      <%= icon_tag "arrow-right" %>
+    </button>
+  <% end %>
+</div>
+
+<% content_for :footer do %>
+  <%= render "sessions/footer" %>
+<% end %>

app/views/signup/new.html.erb

@@ -0,0 +1,28 @@
+<% @page_title = "Sign up for Fizzy" %>
+
+<div class="panel panel--centered flex flex-column gap-half <%= "shake" if flash[:alert] %>">
+  <h1 class="txt-xx-large margin-block-end-double">Sign up</h1>
+
+  <%= form_with model: @signup, url: signup_path, scope: "signup", class: "flex flex-column gap", data: { turbo: false, controller: "form" } do |form| %>
+    <%= form.email_field :email_address, class: "input", autocomplete: "username", placeholder: "Email address", required: true %>
+
+    <% if @signup.errors.any? %>
+      <div class="margin-block-half">
+        <ul class="margin-block-none txt-negative txt-small">
+          <% @signup.errors.full_messages.each do |message| %>
+            <li><%= message %></li>
+          <% end %>
+        </ul>
+      </div>
+    <% end %>
+
+    <button type="submit" class="btn btn--link center" data-form-target="submit">
+      <span>Continue</span>
+      <%= icon_tag "arrow-right" %>
+    </button>
+  <% end %>
+</div>
+
+<% content_for :footer do %>
+  <%= render "sessions/footer" %>
+<% end %>

config/routes.rb

@@ -155,6 +155,12 @@ Rails.application.routes.draw do
     end
   end
 
+  get "/signup/new", to: redirect("/session/new")
+
+  namespace :signup do
+    resource :completion, only: %i[ new create ]
+  end
+
   resource :landing
 
   namespace :my do

db/migrate/20251127000001_create_account_external_id_sequences.rb

@@ -1,6 +1,6 @@
 class CreateAccountExternalIdSequences < ActiveRecord::Migration[8.0]
   def change
-    create_table :account_external_id_sequences do |t|
+    create_table :account_external_id_sequences, id: :uuid do |t|
       t.bigint :value, null: false, default: 0
 
       t.index :value, unique: true

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.2].define(version: 2025_11_25_130010) do
+ActiveRecord::Schema[8.2].define(version: 2025_11_27_000001) do
   create_table "accesses", id: :uuid, charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.datetime "accessed_at"
     t.uuid "account_id", null: false
@@ -25,6 +25,11 @@ ActiveRecord::Schema[8.2].define(version: 2025_11_25_130010) do
     t.index ["user_id"], name: "index_accesses_on_user_id"
   end
 
+  create_table "account_external_id_sequences", id: :uuid, charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
+    t.bigint "value", default: 0, null: false
+    t.index ["value"], name: "index_account_external_id_sequences_on_value", unique: true
+  end
+
   create_table "account_join_codes", id: :uuid, charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.uuid "account_id", null: false
     t.string "code", null: false

db/schema_sqlite.rb

@@ -25,7 +25,7 @@ ActiveRecord::Schema[8.2].define(version: 2025_11_27_000001) do
     t.index ["user_id"], name: "index_accesses_on_user_id"
   end
 
-  create_table "account_external_id_sequences", force: :cascade do |t|
+  create_table "account_external_id_sequences", id: :uuid, force: :cascade do |t|
     t.bigint "value", default: 0, null: false
     t.index ["value"], name: "index_account_external_id_sequences_on_value", unique: true
   end

test/controllers/sessions_controller_test.rb

@@ -21,6 +21,20 @@ class SessionsControllerTest < ActionDispatch::IntegrationTest
     end
   end
 
+  test "create for a new user" do
+    untenanted do
+      assert_difference -> { Identity.count }, +1 do
+        assert_difference -> { MagicLink.count }, +1 do
+          post session_path,
+            params: { email_address: "nonexistent-#{SecureRandom.hex(6)}@example.com" }
+        end
+      end
+
+      assert_redirected_to session_magic_link_path
+    end
+  end
+
+  private
     test "destroy" do
       sign_in_as :kevin
 

test/controllers/signup/completions_controller_test.rb

@@ -0,0 +1,43 @@
+require "test_helper"
+
+class Signup::CompletionsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @signup = Signup.new(email_address: "newuser@example.com", full_name: "New User")
+
+    @signup.create_identity || raise("Failed to create identity")
+
+    sign_in_as @signup.identity
+  end
+
+  test "new" do
+    untenanted do
+      get new_signup_completion_path
+    end
+
+    assert_response :success
+  end
+
+  test "create" do
+    untenanted do
+      post signup_completion_path, params: {
+        signup: {
+          full_name: @signup.full_name
+        }
+      }
+    end
+
+    assert_response :redirect, "Valid params should redirect"
+  end
+
+  test "create with invalid params" do
+    untenanted do
+      post signup_completion_path, params: {
+        signup: {
+          full_name: ""
+        }
+      }
+    end
+
+    assert_response :unprocessable_entity, "Invalid params should return unprocessable entity"
+  end
+end

test/models/signup/account_name_generator_test.rb

@@ -0,0 +1,61 @@
+require "test_helper"
+
+class Signup::AccountNameGeneratorTest < ActiveSupport::TestCase
+  setup do
+    @identity = Identity.create!(email_address: "newart.userbaum@example.com")
+    @name = "Newart userbaum"
+    @generator = Signup::AccountNameGenerator.new(identity: @identity, name: @name)
+  end
+
+  test "generate" do
+    account_name = @generator.generate
+    assert_equal "Newart's Fizzy", account_name, "The 1st account doesn't have 1st in the name"
+
+    first_account = Account.create!(external_account_id: "1st", name: account_name)
+    Current.without_account do
+      @identity.users.create!(account: first_account, name: @name)
+      @identity.reload
+    end
+
+    account_name = @generator.generate
+    assert_equal "Newart's 2nd Fizzy", account_name
+
+    second_account = Account.create!(external_account_id: "2nd", name: account_name)
+    Current.without_account do
+      @identity.users.create!(account: second_account, name: @name)
+      @identity.reload
+    end
+
+    account_name = @generator.generate
+    assert_equal "Newart's 3rd Fizzy", account_name
+
+    third_account = Account.create!(external_account_id: "3rd", name: account_name)
+    Current.without_account do
+      @identity.users.create!(account: third_account, name: @name)
+      @identity.reload
+    end
+
+    account_name = @generator.generate
+    assert_equal "Newart's 4th Fizzy", account_name
+
+    fourth_account = Account.create!(external_account_id: "4th", name: account_name)
+    Current.without_account do
+      @identity.users.create!(account: fourth_account, name: @name)
+      @identity.reload
+    end
+
+    account_name = @generator.generate
+    assert_equal "Newart's 5th Fizzy", account_name
+  end
+
+  test "generate continues from the previous highest index" do
+    account = Account.create!(external_account_id: "12th", name: "Newart's 12th Fizzy")
+    Current.without_account do
+      @identity.users.create!(account: account, name: @name)
+      @identity.reload
+    end
+
+    account_name = @generator.generate
+    assert_equal "Newart's 13th Fizzy", account_name
+  end
+end

test/models/signup_test.rb

@@ -0,0 +1,54 @@
+require "test_helper"
+
+class SignupTest < ActiveSupport::TestCase
+  test "#create_identity" do
+    signup = Signup.new(email_address: "brian@example.com")
+
+    assert_difference -> { Identity.count }, 1 do
+      assert_difference -> { MagicLink.count }, 1 do
+        assert signup.create_identity
+      end
+    end
+
+    assert_empty signup.errors
+    assert signup.identity
+    assert signup.identity.persisted?
+
+    signup_existing = Signup.new(email_address: "brian@example.com")
+
+    assert_no_difference -> { Identity.count } do
+      assert_difference -> { MagicLink.count }, 1 do
+        assert signup_existing.create_identity, "Should send magic link for existing identity"
+      end
+    end
+
+    signup_invalid = Signup.new(email_address: "")
+    assert_raises do
+      signup_invalid.create_identity
+    end
+  end
+
+  test "#complete" do
+    Account.any_instance.expects(:setup_customer_template).once
+
+    Current.without_account do
+      signup = Signup.new(
+        full_name: "Kevin",
+        identity: identities(:kevin)
+      )
+
+      assert signup.complete
+
+      assert signup.account
+      assert signup.user
+      assert_equal "Kevin", signup.user.name
+
+      signup_invalid = Signup.new(
+        full_name: "",
+        identity: identities(:kevin)
+      )
+      assert_not signup_invalid.complete
+      assert_not_empty signup_invalid.errors[:full_name]
+    end
+  end
+end