Add REST API for creating an account (#9572)

* Add REST API for creating an account

The method is available to apps with a token obtained via the client
credentials grant. It creates a user and account records, as well as
an access token for the app that initiated the request. The user is
unconfirmed, and an e-mail is sent as usual.

The method returns the access token, which the app should save for
later. The REST API is not available to users with unconfirmed
accounts, so the app must be smart to wait for the user to click a
link in their e-mail inbox.

The method is rate-limited by IP to 5 requests per 30 minutes.

* Redirect users back to app from confirmation if they were created with an app

* Add tests

* Return 403 on the method if registrations are not open

* Require agreement param to be true in the API when creating an account

app/controllers/api/base_controller.rb

@@ -68,7 +68,7 @@ class Api::BaseController < ApplicationController
   end
 
   def require_user!
-    if current_user && !current_user.disabled?
+    if current_user && !current_user.disabled? && current_user.confirmed?
       set_user_activity
     elsif current_user
       render json: { error: 'Your login is currently disabled' }, status: 403

app/controllers/api/v1/accounts_controller.rb

@@ -1,14 +1,16 @@
 # frozen_string_literal: true
 
 class Api::V1::AccountsController < Api::BaseController
-  before_action -> { authorize_if_got_token! :read, :'read:accounts' }, except: [:follow, :unfollow, :block, :unblock, :mute, :unmute]
+  before_action -> { authorize_if_got_token! :read, :'read:accounts' }, except: [:create, :follow, :unfollow, :block, :unblock, :mute, :unmute]
   before_action -> { doorkeeper_authorize! :follow, :'write:follows' }, only: [:follow, :unfollow]
   before_action -> { doorkeeper_authorize! :follow, :'write:mutes' }, only: [:mute, :unmute]
   before_action -> { doorkeeper_authorize! :follow, :'write:blocks' }, only: [:block, :unblock]
+  before_action -> { doorkeeper_authorize! :write, :'write:accounts' }, only: [:create]
 
-  before_action :require_user!, except: [:show]
-  before_action :set_account
+  before_action :require_user!, except: [:show, :create]
+  before_action :set_account, except: [:create]
   before_action :check_account_suspension, only: [:show]
+  before_action :check_enabled_registrations, only: [:create]
 
   respond_to :json
 
@@ -16,6 +18,16 @@ class Api::V1::AccountsController < Api::BaseController
     render json: @account, serializer: REST::AccountSerializer
   end
 
+  def create
+    token    = AppSignUpService.new.call(doorkeeper_token.application, account_params)
+    response = Doorkeeper::OAuth::TokenResponse.new(token)
+
+    headers.merge!(response.headers)
+
+    self.response_body = Oj.dump(response.body)
+    self.status        = response.status
+  end
+
   def follow
     FollowService.new.call(current_user.account, @account, reblogs: truthy_param?(:reblogs))
 
@@ -62,4 +74,12 @@ class Api::V1::AccountsController < Api::BaseController
   def check_account_suspension
     gone if @account.suspended?
   end
+
+  def account_params
+    params.permit(:username, :email, :password, :agreement)
+  end
+
+  def check_enabled_registrations
+    forbidden if single_user_mode? || !Setting.open_registrations
+  end
 end

app/controllers/auth/confirmations_controller.rb

@@ -6,9 +6,9 @@ class Auth::ConfirmationsController < Devise::ConfirmationsController
   before_action :set_body_classes
   before_action :set_user, only: [:finish_signup]
 
-  # GET/PATCH /users/:id/finish_signup
   def finish_signup
     return unless request.patch? && params[:user]
+
     if @user.update(user_params)
       @user.skip_reconfirmation!
       bypass_sign_in(@user)
@@ -31,4 +31,12 @@ class Auth::ConfirmationsController < Devise::ConfirmationsController
   def user_params
     params.require(:user).permit(:email)
   end
+
+  def after_confirmation_path_for(_resource_name, user)
+    if user.created_by_application && truthy_param?(:redirect_to_app)
+      user.created_by_application.redirect_uri
+    else
+      super
+    end
+  end
 end

app/controllers/auth/registrations_controller.rb

@@ -26,6 +26,7 @@ class Auth::RegistrationsController < Devise::RegistrationsController
 
     resource.locale      = I18n.locale
     resource.invite_code = params[:invite_code] if resource.invite_code.blank?
+    resource.agreement   = true
 
     resource.build_account if resource.account.nil?
   end

app/models/user.rb

@@ -36,6 +36,7 @@
 #  invite_id                 :bigint(8)
 #  remember_token            :string
 #  chosen_languages          :string           is an Array
+#  created_by_application_id :bigint(8)
 #
 
 class User < ApplicationRecord
@@ -66,6 +67,7 @@ class User < ApplicationRecord
 
   belongs_to :account, inverse_of: :user
   belongs_to :invite, counter_cache: :uses, optional: true
+  belongs_to :created_by_application, class_name: 'Doorkeeper::Application', optional: true
   accepts_nested_attributes_for :account
 
   has_many :applications, class_name: 'Doorkeeper::Application', as: :owner
@@ -74,6 +76,7 @@ class User < ApplicationRecord
   validates :locale, inclusion: I18n.available_locales.map(&:to_s), if: :locale?
   validates_with BlacklistedEmailValidator, if: :email_changed?
   validates_with EmailMxValidator, if: :validate_email_dns?
+  validates :agreement, acceptance: { allow_nil: false, accept: [true, 'true', '1'] }, on: :create
 
   scope :recent, -> { order(id: :desc) }
   scope :admins, -> { where(admin: true) }
@@ -294,7 +297,7 @@ class User < ApplicationRecord
       end
 
     if resource.blank?
-      resource = new(email: attributes[:email])
+      resource = new(email: attributes[:email], agreement: true)
       if Devise.check_at_sign && !resource[:email].index('@')
         resource[:email] = Rpam2.getenv(resource.find_pam_service, attributes[:email], attributes[:password], 'email', false)
         resource[:email] = "#{attributes[:email]}@#{resource.find_pam_suffix}" unless resource[:email]
@@ -307,7 +310,7 @@ class User < ApplicationRecord
     resource = joins(:account).find_by(accounts: { username: attributes[Devise.ldap_uid.to_sym].first })
 
     if resource.blank?
-      resource = new(email: attributes[:mail].first, account_attributes: { username: attributes[Devise.ldap_uid.to_sym].first })
+      resource = new(email: attributes[:mail].first, agreement: true, account_attributes: { username: attributes[Devise.ldap_uid.to_sym].first })
       resource.ldap_setup(attributes)
     end
 

app/services/app_sign_up_service.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+class AppSignUpService < BaseService
+  def call(app, params)
+    return unless allowed_registrations?
+
+    user_params    = params.slice(:email, :password, :agreement)
+    account_params = params.slice(:username)
+    user           = User.create!(user_params.merge(created_by_application: app, password_confirmation: user_params[:password], account_attributes: account_params))
+
+    Doorkeeper::AccessToken.create!(application: app,
+                                    resource_owner_id: user.id,
+                                    scopes: app.scopes,
+                                    expires_in: Doorkeeper.configuration.access_token_expires_in,
+                                    use_refresh_token: Doorkeeper.configuration.refresh_token_enabled?)
+  end
+
+  private
+
+  def allowed_registrations?
+    Setting.open_registrations && !Rails.configuration.x.single_user_mode
+  end
+end

app/views/user_mailer/confirmation_instructions.html.haml

@@ -55,8 +55,12 @@
                             %tbody
                               %tr
                                 %td.button-primary
-                                  = link_to confirmation_url(@resource, confirmation_token: @token) do
-                                    %span= t 'devise.mailer.confirmation_instructions.action'
+                                  - if @resource.created_by_application
+                                    = link_to confirmation_url(@resource, confirmation_token: @token, redirect_to_app: 'true') do
+                                      %span= t 'devise.mailer.confirmation_instructions.action_with_app', app: @resource.created_by_application.name
+                                  - else
+                                    = link_to confirmation_url(@resource, confirmation_token: @token) do
+                                      %span= t 'devise.mailer.confirmation_instructions.action'
 
 %table.email-table{ cellspacing: 0, cellpadding: 0 }
   %tbody

app/views/user_mailer/confirmation_instructions.text.erb

@@ -4,7 +4,7 @@
 
 <%= t 'devise.mailer.confirmation_instructions.explanation', host: site_hostname %>
 
-=> <%= confirmation_url(@resource, confirmation_token: @token) %>
+=> <%= confirmation_url(@resource, confirmation_token: @token, redirect_to_app: @resource.created_by_application ? 'true' : nil) %>
 
 <%= strip_tags(t('devise.mailer.confirmation_instructions.extra_html', terms_path: about_more_url, policy_path: terms_url)) %>
 

config/initializers/rack_attack.rb

@@ -57,6 +57,10 @@ class Rack::Attack
     req.authenticated_user_id if req.post? && req.path.start_with?('/api/v1/media')
   end
 
+  throttle('throttle_api_sign_up', limit: 5, period: 30.minutes) do |req|
+    req.ip if req.post? && req.path == '/api/v1/accounts'
+  end
+
   throttle('protected_paths', limit: 25, period: 5.minutes) do |req|
     req.ip if req.post? && req.path =~ PROTECTED_PATHS_REGEX
   end

config/locales/devise.en.yml

@@ -18,6 +18,7 @@ en:
     mailer:
       confirmation_instructions:
         action: Verify email address
+        action_with_app: Confirm and return to %{app}
         explanation: You have created an account on %{host} with this email address. You are one click away from activating it. If this wasn't you, please ignore this email.
         extra_html: Please also check out <a href="%{terms_path}">the rules of the instance</a> and <a href="%{policy_path}">our terms of service</a>.
         subject: 'Mastodon: Confirmation instructions for %{instance}'

config/routes.rb

@@ -336,7 +336,7 @@ Rails.application.routes.draw do
         resources :relationships, only: :index
       end
 
-      resources :accounts, only: [:show] do
+      resources :accounts, only: [:create, :show] do
         resources :statuses, only: :index, controller: 'accounts/statuses'
         resources :followers, only: :index, controller: 'accounts/follower_accounts'
         resources :following, only: :index, controller: 'accounts/following_accounts'

db/migrate/20181219235220_add_created_by_application_id_to_users.rb

@@ -0,0 +1,8 @@
+class AddCreatedByApplicationIdToUsers < ActiveRecord::Migration[5.2]
+  disable_ddl_transaction!
+
+  def change
+    add_reference :users, :created_by_application, foreign_key: { to_table: 'oauth_applications', on_delete: :nullify }, index: false
+    add_index :users, :created_by_application_id, algorithm: :concurrently
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2018_12_13_185533) do
+ActiveRecord::Schema.define(version: 2018_12_19_235220) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -637,8 +637,10 @@ ActiveRecord::Schema.define(version: 2018_12_13_185533) do
     t.bigint "invite_id"
     t.string "remember_token"
     t.string "chosen_languages", array: true
+    t.bigint "created_by_application_id"
     t.index ["account_id"], name: "index_users_on_account_id"
     t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
+    t.index ["created_by_application_id"], name: "index_users_on_created_by_application_id"
     t.index ["email"], name: "index_users_on_email", unique: true
     t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
   end
@@ -730,6 +732,7 @@ ActiveRecord::Schema.define(version: 2018_12_13_185533) do
   add_foreign_key "subscriptions", "accounts", name: "fk_9847d1cbb5", on_delete: :cascade
   add_foreign_key "users", "accounts", name: "fk_50500f500d", on_delete: :cascade
   add_foreign_key "users", "invites", on_delete: :nullify
+  add_foreign_key "users", "oauth_applications", column: "created_by_application_id", on_delete: :nullify
   add_foreign_key "web_push_subscriptions", "oauth_access_tokens", column: "access_token_id", on_delete: :cascade
   add_foreign_key "web_push_subscriptions", "users", on_delete: :cascade
   add_foreign_key "web_settings", "users", name: "fk_11910667b2", on_delete: :cascade

lib/mastodon/accounts_cli.rb

@@ -73,7 +73,7 @@ module Mastodon
     def create(username)
       account  = Account.new(username: username)
       password = SecureRandom.hex
-      user     = User.new(email: options[:email], password: password, admin: options[:role] == 'admin', moderator: options[:role] == 'moderator', confirmed_at: Time.now.utc)
+      user     = User.new(email: options[:email], password: password, agreement: true, admin: options[:role] == 'admin', moderator: options[:role] == 'moderator', confirmed_at: options[:confirmed] ? Time.now.utc : nil)
 
       if options[:reattach]
         account = Account.find_local(username) || Account.new(username: username)

spec/controllers/api/v1/accounts_controller_spec.rb

@@ -19,6 +19,40 @@ RSpec.describe Api::V1::AccountsController, type: :controller do
     end
   end
 
+  describe 'POST #create' do
+    let(:app) { Fabricate(:application) }
+    let(:token) { Doorkeeper::AccessToken.find_or_create_for(app, nil, 'read write', nil, false) }
+    let(:agreement) { nil }
+
+    before do
+      post :create, params: { username: 'test', password: '12345678', email: 'hello@world.tld', agreement: agreement }
+    end
+
+    context 'given truthy agreement' do
+      let(:agreement) { 'true' }
+
+      it 'returns http success' do
+        expect(response).to have_http_status(200)
+      end
+
+      it 'returns a new access token as JSON' do
+        expect(body_as_json[:access_token]).to_not be_blank
+      end
+
+      it 'creates a user' do
+        user = User.find_by(email: 'hello@world.tld')
+        expect(user).to_not be_nil
+        expect(user.created_by_application_id).to eq app.id
+      end
+    end
+
+    context 'given no agreement' do
+      it 'returns http unprocessable entity' do
+        expect(response).to have_http_status(422)
+      end
+    end
+  end
+
   describe 'GET #show' do
     let(:scopes) { 'read:accounts' }
 

spec/fabricators/user_fabricator.rb

@@ -3,4 +3,5 @@ Fabricator(:user) do
   email        { sequence(:email) { |i| "#{i}#{Faker::Internet.email}" } }
   password     "123456789"
   confirmed_at { Time.zone.now }
+  agreement    true
 end

spec/models/user_spec.rb

@@ -106,19 +106,19 @@ RSpec.describe User, type: :model do
     end
 
     it 'should allow a non-blacklisted user to be created' do
-      user = User.new(email: 'foo@example.com', account: account, password: password)
+      user = User.new(email: 'foo@example.com', account: account, password: password, agreement: true)
 
       expect(user.valid?).to be_truthy
     end
 
     it 'should not allow a blacklisted user to be created' do
-      user = User.new(email: 'foo@mvrht.com', account: account, password: password)
+      user = User.new(email: 'foo@mvrht.com', account: account, password: password, agreement: true)
 
       expect(user.valid?).to be_falsey
     end
 
     it 'should not allow a subdomain blacklisted user to be created' do
-      user = User.new(email: 'foo@mvrht.com.topdomain.tld', account: account, password: password)
+      user = User.new(email: 'foo@mvrht.com.topdomain.tld', account: account, password: password, agreement: true)
 
       expect(user.valid?).to be_falsey
     end
@@ -210,17 +210,17 @@ RSpec.describe User, type: :model do
     end
 
     it 'should not allow a user to be created unless they are whitelisted' do
-      user = User.new(email: 'foo@example.com', account: account, password: password)
+      user = User.new(email: 'foo@example.com', account: account, password: password, agreement: true)
       expect(user.valid?).to be_falsey
     end
 
     it 'should allow a user to be created if they are whitelisted' do
-      user = User.new(email: 'foo@mastodon.space', account: account, password: password)
+      user = User.new(email: 'foo@mastodon.space', account: account, password: password, agreement: true)
       expect(user.valid?).to be_truthy
     end
 
     it 'should not allow a user with a whitelisted top domain as subdomain in their email address to be created' do
-      user = User.new(email: 'foo@mastodon.space.userdomain.com', account: account, password: password)
+      user = User.new(email: 'foo@mastodon.space.userdomain.com', account: account, password: password, agreement: true)
       expect(user.valid?).to be_falsey
     end
 
@@ -242,7 +242,7 @@ RSpec.describe User, type: :model do
 
   it_behaves_like 'Settings-extended' do
     def create!
-      User.create!(account: Fabricate(:account), email: 'foo@mastodon.space', password: 'abcd1234')
+      User.create!(account: Fabricate(:account), email: 'foo@mastodon.space', password: 'abcd1234', agreement: true)
     end
 
     def fabricate

spec/services/app_sign_up_service_spec.rb

@@ -0,0 +1,41 @@
+require 'rails_helper'
+
+RSpec.describe AppSignUpService, type: :service do
+  let(:app) { Fabricate(:application, scopes: 'read write') }
+  let(:good_params) { { username: 'alice', password: '12345678', email: 'good@email.com', agreement: true } }
+
+  subject { described_class.new }
+
+  describe '#call' do
+    it 'returns nil when registrations are closed' do
+      Setting.open_registrations = false
+      expect(subject.call(app, good_params)).to be_nil
+    end
+
+    it 'raises an error when params are missing' do
+      expect { subject.call(app, {}) }.to raise_error ActiveRecord::RecordInvalid
+    end
+
+    it 'creates an unconfirmed user with access token' do
+      access_token = subject.call(app, good_params)
+      expect(access_token).to_not be_nil
+      user = User.find_by(id: access_token.resource_owner_id)
+      expect(user).to_not be_nil
+      expect(user.confirmed?).to be false
+    end
+
+    it 'creates access token with the app\'s scopes' do
+      access_token = subject.call(app, good_params)
+      expect(access_token).to_not be_nil
+      expect(access_token.scopes.to_s).to eq 'read write'
+    end
+
+    it 'creates an account' do
+      access_token = subject.call(app, good_params)
+      expect(access_token).to_not be_nil
+      user = User.find_by(id: access_token.resource_owner_id)
+      expect(user).to_not be_nil
+      expect(user.account).to_not be_nil
+    end
+  end
+end