Link up a new user to an existing deploy only user

app/controllers/users_controller.rb

@@ -22,7 +22,9 @@ def edit
   end
 
   def create
-    @user = User.new(user_params)
+    @user = User.find_or_initialize_by(username: user_params[:username])
+    @user.assign_attributes(user_params)
+
     invite_link = InviteLink.active.find_by(code: params[:code])
 
     respond_to do |format|

app/models/user.rb

@@ -10,6 +10,8 @@ class User < ApplicationRecord
   has_secure_password validations: false
   validates :password, length: {minimum: 10, maximum: 72}, if: -> { password.present? }
 
+  validates :username, presence: true, uniqueness: true
+
   after_create_commit :queue_import_avatar
 
   scope :has_role, -> { where.not(role: nil) }

db/migrate/20241030224628_add_index_to_users_username.rb

@@ -0,0 +1,5 @@
+class AddIndexToUsersUsername < ActiveRecord::Migration[7.2]
+  def change
+    add_index :users, :username, unique: true
+  end
+end

test/controllers/users_controller_test.rb

@@ -18,6 +18,19 @@ class UsersControllerTest < ActionDispatch::IntegrationTest
       assert_response :unprocessable_entity
     end
 
+    test "should create with existing deploy user" do
+      invite_link = InviteLink.create!(role: :admin)
+      user = create(:user, password: nil, username: "nickhammond")
+
+      assert_no_difference("User.count") do
+        post users_url, params: {code: invite_link.code, user: {email: user.email, name: user.name, password: "secretsecret", username: user.username}}
+      end
+
+      assert_redirected_to root_url
+      assert_equal user, User.last
+      assert User.last.admin?
+    end
+
     test "should create user" do
       invite_link = InviteLink.create!(role: :user)
       user = build(:user)

test/factories/users.rb

@@ -1,6 +1,7 @@
 FactoryBot.define do
   factory :user do
     sequence(:email) { |n| "person#{n}@example.com" }
+    sequence(:username) { |n| "user#{n}" }
     name { "MyString" }
     password { "secretsecret" }
   end