Rails: The Missing Parts

1. the missing parts Radoslav Stankov
2. !
3. Radoslav Stankov @rstankov rstankov.com
4. https://tips.rstankov.com
7. - one developer (me) " - management portal # - implement a mobile app $ - for iOS % / Android &
9. source: https://refactoring.fm/p/how-to-choose-technology
12. source "https://rubygems.org" # Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main" gem "rails", "~> 8.0.0.rc1" # The modern asset pipeline for Rails [https://github.com/rails/propshaft] gem "propshaft" # Use sqlite3 as the database for Active Record gem "sqlite3", ">= 2.1" # Use the Puma web server [https://github.com/puma/puma] gem "puma", ">= 5.0" # Use JavaScript with ESM import maps [https://github.com/rails/importmap-rails] gem "importmap-rails" # Hotwire's SPA-like page accelerator [https://turbo.hotwired.dev] gem "turbo-rails" # Hotwire's modest JavaScript framework [https://stimulus.hotwired.dev] gem "stimulus-rails" # Build JSON APIs with ease [https://github.com/rails/jbuilder] gem "jbuilder" # Use Active Model has_secure_password [https://guides.rubyonrails.org/active_model_basics.html#securepassword] # gem "bcrypt", "~> 3.1.7" # Windows does not include zoneinfo files, so bundle the tzinfo-data gem gem "tzinfo-data", platforms: %i[ windows jruby ] # Use the database-backed adapters for Rails.cache, Active Job, and Action Cable gem "solid_cache" gem "solid_queue" gem "solid_cable" # Reduces boot times through caching; required in config/boot.rb gem "bootsnap", require: false # Deploy this application anywhere as a Docker container [https://kamal-deploy.org] gem "kamal", require: false # Add HTTP asset caching/compression and X-Sendfile acceleration to Puma [https://github.com/basecamp/thruster/] gem "thruster", require: false # Use Active Storage variants [https://guides.rubyonrails.org/active_storage_overview.html#transforming-images] # gem "image_processing", "~> 1.2" group :development, :test do # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem gem "debug", platforms: %i[ mri windows ], require: "debug/prelude" # Static analysis for security vulnerabilities [https://brakemanscanner.org/] gem "brakeman", require: false # Omakase Ruby styling [https://github.com/rails/rubocop-rails-omakase/] gem "rubocop-rails-omakase", require: false end group :development do # Use console on exceptions pages [https://github.com/rails/web-console] gem "web-console" end group :test do # Use system testing [https://guides.rubyonrails.org/testing.html#system-testing] gem "capybara" gem "selenium-webdriver" end
15. ' Rails extensions ( Missing concepts ) Agenda
16. * Rails extensions Active Record Routing Error Handling I18n
17. Active Record
18. gem 'annotate' # == Schema Information # # Table name: building_print_templates # # id :bigint(8) not null, primary key # format :string not null # name :string not null # options :jsonb not null # created_at :datetime not null # updated_at :datetime not null # account_id :bigint(8) not null # user_id :bigint(8) # # Indexes # # index_building_print_templates_on_account_id_and_name (account_id,name) UNIQUE # index_building_print_templates_on_user_id (user_id) # # Foreign Keys # # fk_rails_... (account_id => accounts.id) # fk_rails_... (user_id => users.id) # class Buildings::PrintTemplate < ApplicationRecord
19. gem 'counter_culture' class Apartment < ApplicationRecord belongs :building # will track active and archived apartments separately counter_culture :building, column_name: -> { _1.active? ? :apartments_count : :archived_apartments_count } # can do this for the whole account counter_culture %i(building account), column_name: -> { _1.building.active? && _1.active? ? :apartments_count : :arch # can track a sum of a columns counter_culture :building, column_name: :unpaid_taxes_amount, delta_magnitude: -> { _1.unpaid_taxes_amount }
 counter_culture :building, column_name: :deposit_amount, delta_magnitude: -> { _1.deposit_amount } end
20. class Note < ApplicationRecord belongs_to :user, optional: true belongs_to_polymorphic :resource, allowed_classes: [ Apartment, Building, ImprovementTax, Calendar::Event, Transaction, Tasks::Task ] end
21. ...kinda like "delegated_type" +
22. class Issues::Activity < ApplicationRecord extension HasAuditLog, except: %i(notified_at) extension AngrySupport::TimeAsBoolean, field_name: :approved extension AngrySupport::TimeAsBoolean, field_name: :notified extension Notifications::Subject # ... end
23. ...kinda like "concerns" +
24. module AngrySupport::TimeAsBoolean extend self def define(model, field_name:, reverse: nil) column_name = "#{field_name}_at" model.scope field_name, -> { where(arel_table[column_name].lteq(Time.current)) } model.define_method(:"#{field_name}?") do value = public_send(column_name) value.present? && !value.future? end model.alias_method field_name, "#{field_name}?" model.define_method(:"#{field_name}=") do |value| if value.present? if value.acts_like?(:time) public_send(:"#{column_name}=", value) elsif !public_send(field_name) public_send(:"#{column_name}=", Time.current) end else public_send(:"#{column_name}=", nil) end end if reverse model.scope reverse, -> { where(column_name => nil).or(where(arel_table[column_name].gteq(Time.current))) } model.define_method(:"#{reverse}?") { !public_send(field_name) } else model.scope "not_#{field_name}", -> { where(column_name => nil) } end end end
25. module AngrySupport::ActiveRecordExtension def extension(extension_module, *args, **kwargs) extension_module.define(self, *args, **kwargs) if extension_module.respond_to?(:define) extend(extension_module.const_get(:ClassMethods)) if extension_module.const_defined?(:ClassMethods) include(extension_module.const_get(:InstanceMethods)) if extension_module.const_defined?(:InstanceMethods) end end
26. Routing
27. How to use routes helpers outside ActionPack / ActionMailer? ,
28. module Routes class << self include Rails.application.routes.url_helpers include Routes::Custom def default_url_options Rails.application.default_url_options end end end
29. How to use "url_for" my models that don't have proper urls setup? -
30. module Routes::Custom def record_path(record) case record when Accounts::Member then account_member_path(record) when Print::BuildingTemplate then print_template_path(record) when Calendar::Event then event_path(record) when Finance::BulkWithdraw then bulk_withdraw_path(record) when Issues::Type then issue_type_path(record) when Messaging::Bulk then bulk_message_path(record) when Messaging::Message then message_path(record) when MoneyTransfer then transaction_path(record) when PaymentImport::Entry then payment_import_path(record) when Tasks::RecurringTask then recurring_task_path(record) when Tasks::Task then task_path(record) when Taxation::Payment then payment_path(record) when Taxation::PaymentDocument then payment_document_path(record) else url_for(record) end end def record_url(record) #.... end
 
 # ... end
31. Error Handling
32. module ErrorReporting extend self def assign_user(user) return unless Rails.env.production? Sentry.set_user(...) end def capture_exception(error) if Rails.env.production? if error.is_a?(String) Sentry.capture_message(error) else Sentry.capture_exception(error) end else raise error end end def exception_context(prop, hash) Sentry.set_context(prop, hash) if Rails.env.production? end def graphql_path(path) exception_context('graphql_info', path: path) end def job_discarded(job, exception) Rails.logger.error "Discarded #{job.class} due to #{exception.cause.inspect}." exception_context('job', name: job.class.name, arguments: job.arguments) capture_exception(exception) end end
33. https://speakerdeck.com/rstankov/living-without-exceptions
34. I18n
35. . / 0
36. def t_display(to_display) if to_display.is_a?(Symbol) t(to_display) elsif to_display.is_a?(String) to_display elsif to_display.respond_to?(:display_name) to_display.display_name elsif to_display.respond_to?(:name) to_display.name elsif to_display.respond_to?(:title) to_display.title else to_display.to_s end end def t_options(collection) collection.map { [t_display(_1), _1.id] } end def t_enum(enum, i18n_key) enum.keys.map { [t("#{i18n_key}_#{_1}"), _1] } end
37. rails translate:check_translations 1. Check for missing translations 2. Raises errors rails translate:fill_in_missing_translations 1. Compare all config/locales/[lang].yaml 2. Find missing keys 3. Prompt OpenAI API for translations 4. Add new translations 5. Format YAML (sort keys)
38. • Raise error in development • Don't use nested keys! • Use prefixes • "table_column_#{name}" • "page_title_#{controller_name}" • Use defaults • t("table_column_#{name}", default: :"form_label_#{name}") 1 Rado's tips
39. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
40. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
41. <%= render FieldsetComponent.new(fieldset, title: :bank_account) do %> <%= form.input :bank_account_bank %> <%= form.input :bank_account_iban %> <%= form.input :bank_account_bic %> <% end %>
43. https://speakerdeck.com/rstankov/component-driven-ui-with-viewcomponent-gem
44. https://tips.rstankov.com/p/tips-for-using-viewcomponents-in
45. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
48. module Handle::NetworkErrors extend self ERRORS = [ # ... Faraday::ConnectionFailed, Faraday::TimeoutError, RestClient::BadGateway, RestClient::BadRequest, # ... ] def ===(error) ERRORS.any? { |error_class| error_class === error } end end
50. # Taken from: [url to where those credentials are taken] [sevice_name]_token: [...] [sevice_name]_secret: [...]
51. # Documentation # # - service: [url to service] # - manage: [url to manage tokens] # - api: [url to api documentation] # - gem: [gem we are using (optional)] # [- ... other links] module External::[Service]Api extend self # documentation: [documentation] def perform_action(args) # use HTTParty or gem for this external service end end
52. # Documentation # # - service: https://unsplash.com/ # - api: https://unsplash.com/documentation # - gem: https://github.com/unsplash/unsplash_rb # - portal: https://unsplash.com/oauth/applications module External::UnsplashApi extend self # documentation: https://unsplash.com/documentation#search-photos def search(query) Unsplash::Photo.search(query, 1, 12, 'landscape') end # documentation: https://unsplash.com/documentation#get-a-photo # documentation: https://unsplash.com/documentation#track-a-photo-download def track_download(id) photo = Unsplash::Photo.find(id) photo.track_download rescue Unsplash::NotFoundError nil end end
53. ✅ Store credentials in "config/credentials.yml.enc" ✅ Facade around every network call in "External" module ✅ Add logging and error handling around network calls https://tips.rstankov.com/p/tips-for-dealing-with-external-services
54. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
55. KittyPolicy https://github.com/producthunt/kitty-policy
56. module ApplicationPolicy extend self def can_access_account?(user, account) return false if user.nil? user.admin? || account.member?(user) end end
57. module ApplicationPolicy extend KittyPolicy::DSL can :access, Account do |user, account| user.admin? || account.member?(user) end end # generates ApplicationPolicy.can_access_account?(user, account) # can be accessed as ApplicationPolicy.can?(user, :access, account) ApplicationPolicy.authorize!(user, :access, account) # raise KittyPolicy::AccessDenied
58. module ApplicationPolicy extend KittyPolicy::DSL extend ApplicationPolicy::RolesDSL # Role stacking. # Upper role can do everything lower role can do
 # # - director > supervisor > operator > cashier # - chief technician > technician # - chief accountant > accountant building_cashier_can :view, Withdraw building_operator_can :create, Withdraw building_supervisor_can :update, Withdraw building_director_can :destroy, Withdraw # ... end
59. wc -l < app/lib/application_policy.rb 273
60. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
61. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
62. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
63. render template: 'system/feature_unavailable' end rescue_from KittyPolicy::AccessDenied do |error| ErrorReporting.capture_exception(error) render template: 'system/unauthorized' end end class_methods do def require_account_feature(feature_name) self.required_account_feature = feature_name end end private def find_record(scope, id = :none, authorize: :view) record = scope.find(id == :none ? params[:id] : id) ApplicationPolicy.authorize!(current_user, authorize, record) if self.class.required_account_feature.present? Accounts.feature_available!(record, self.class.required_account_feature) end
64. private def find_record(scope, id = :none, authorize: :view) record = scope.find(id == :none ? params[:id] : id) ApplicationPolicy.authorize!(current_user, authorize, record) if self.class.required_account_feature.present? Accounts.feature_available!(record, self.class.required_account_feature) end record end end
65. module Accounts extend self def account_of(record) if record.is_a?(Account) record elsif record.respond_to?(:account) record.account elsif record.respond_to?(:building) record.building.account else raise "Can't find account for #{record.class}##{record.id}" end end def feature_available?(record, feature_name) account_of(record).features.available?(feature_name) end def feature_available!(record, feature_name) return if feature_available?(record, feature_name) raise FeatureUnavailable.new(record, feature_name) end end
66. KittyPolicy https://github.com/producthunt/kitty-policy
67. module ApplicationPolicy extend self def can_access_account?(user, account) return false if user.nil? user.admin? || account.member?(user) end end
68. module ApplicationPolicy extend KittyPolicy::DSL can :access, Account do |user, account| user.admin? || account.member?(user) end end # generates ApplicationPolicy.can_access_account?(user, account) # can be accessed as ApplicationPolicy.can?(user, :access, account) ApplicationPolicy.authorize!(user, :access, account) # raise KittyPolicy::AccessDenied
69. module ApplicationPolicy extend KittyPolicy::DSL extend ApplicationPolicy::RolesDSL # Role stacking. # Upper role can do everything lower role can do
 # # - director > supervisor > operator > cashier # - chief technician > technician # - chief accountant > accountant building_cashier_can :view, Withdraw building_operator_can :create, Withdraw building_supervisor_can :update, Withdraw building_director_can :destroy, Withdraw # ... end
70. wc -l < app/lib/application_policy.rb 273
71. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
72. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
73. class CalendarEventsController < ApplicationController require_account_feature :calendar def show @event = find_record Calendar::Event end def edit @event = find_record Calendar::Event, params[:id], authorize: :manage end
 # ... end
74. render template: 'system/feature_unavailable' end rescue_from KittyPolicy::AccessDenied do |error| ErrorReporting.capture_exception(error) render template: 'system/unauthorized' end end class_methods do def require_account_feature(feature_name) self.required_account_feature = feature_name end end private def find_record(scope, id = :none, authorize: :view) record = scope.find(id == :none ? params[:id] : id) ApplicationPolicy.authorize!(current_user, authorize, record) if self.class.required_account_feature.present? Accounts.feature_available!(record, self.class.required_account_feature) end
75. private def find_record(scope, id = :none, authorize: :view) record = scope.find(id == :none ? params[:id] : id) ApplicationPolicy.authorize!(current_user, authorize, record) if self.class.required_account_feature.present? Accounts.feature_available!(record, self.class.required_account_feature) end record end end
76. module Accounts extend self def account_of(record) if record.is_a?(Account) record elsif record.respond_to?(:account) record.account elsif record.respond_to?(:building) record.building.account else raise "Can't find account for #{record.class}##{record.id}" end end def feature_available?(record, feature_name) account_of(record).features.available?(feature_name) end def feature_available!(record, feature_name) return if feature_available?(record, feature_name) raise FeatureUnavailable.new(record, feature_name) end end
77. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
78. module Taxation::PaymentCreate extend self def call(arguments) # ... end private # ... end
79. I don't have many "service objects". In most cases, the "service object", I inline it in a "form object".
80. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
81. MiniForm (Syntax sugar around ActiveModel::Model) https://github.com/RStankov/MiniForm
82. class Calendar::AttendeeForm < ApplicationForm main_model( :attendee, attributes: %i(user_id), read: %i(event building), save: true ) validate :ensure_user_is_allowed def initialize(event) @attendee = event.attendees.new end def user_options @user_options ||= building.account.member_users end def perform Notifications.notify_about(@attendee) end private def ensure_user_is_allowed
83. class ApplicationForm include MiniForm::Model def submit(params) update(params.require(:form).permit(self.class.attribute_names)) end def submit!(params) update!(params.require(:form).permit(self.class.attribute_names)) end end
84. class ApplicationForm include MiniForm::Model def submit(params) update(params.require(:form).permit(self.class.attribute_names)) end def submit!(params) update!(params.require(:form).permit(self.class.attribute_names)) end end module ApplicationHelper def app_form(record, options = {}) options[:as] ||= :form 
 # ... end # ...
85. class CalendarEventAttendeesController < ApplicationController require_account_feature :calendar def new @attendee = Calendar::AttendeeForm.new(find_event) end def create @attendee = Calendar::AttendeeForm.new(find_event) @attendee.submit(params) respond_with @attendee, location: event_path(@attendee.event) end private def find_event find_record Calendar::Event, params[:event_id] end end
86. class CalendarEventAttendeesController < ApplicationController require_account_feature :calendar def new @attendee = Calendar::AttendeeForm.new(find_event) end def create @attendee = Calendar::AttendeeForm.new(find_event) @attendee.submit(params) respond_with @attendee, location: event_path(@attendee.event) end private def find_event find_record Calendar::Event, params[:event_id] end end gem 'responders'
87. I keep business logic in the form object, except if it is going to be used somewhere else. I follow the same logic for ActiveJob objects.
88. 2 Missing concepts View Components External services Policy objects Service objects Form objects Query objects
90. Search form
91. Search form Statistics based on search
92. Search form Statistics based on search Search results
93. SearchObject https://github.com/RStankov/SearchObject
94. search = Finance::TransactionsSearch.new(filters: params[:filters]) search.results
95. class Finance::TransactionsSearch def initialize(filters: {}) @filters = filters end def results scope = Transaction.all scope = scope.where(user_id: @filters[:user_id]) if @filters[:user_id] scope = scope.where("amount > ?", @filters[:min_amount]) if @filters[:min_amount] scope = scope.where("amount < ?", @filters[:max_amount]) if @filters[:max_amount] scope = scope.where("created_at > ?", @filters[:start_date]) if @filters[:start_d scope = scope.where("created_at < ?", @filters[:end_date]) if @filters[:end_date] scope end end
96. class Finance::TransactionsSearch def initialize(filters: {}, page: 0) @filters = filters @page = page end def results @results ||= fetch_results end def fetch_results scope = Transaction.all scope = scope.where(user_id: @filters[:user_id]) if @filters[:user_id] scope = scope.where("amount > ?", @filters[:min_amount]) if @filters[:min_amount] scope = scope.where("amount < ?", @filters[:max_amount]) if @filters[:max_amount] scope = scope.where("created_at > ?", @filters[:start_date]) if @filters[:start_d scope = scope.where("created_at < ?", @filters[:end_date]) if @filters[:end_date] scope.page(@page) end end
97. class Finance::TransactionsSearch include SearchObject.module(:kaminary) scope { Transaction.all } option(:user_id) option(:min_amount) { |scope, v| scope.where("amount > ?", v) } option(:max_amount) { |scope, v| scope.where("amount < ?", v) } option(:start_date) { |scope, v| scope.where("created_at > ?", v) } option(:end_date) { |scope, v| scope.where("created_at < ?", v) } end
98. class Finance::TransactionsSearch include SearchObject.module(:kaminary) scope { Transaction.all } option :user_id option :min_amount, with: :filter_by_min_amount option :max_amount, with: :filter_by_max_amount option :start_date, with: :filter_by_start_date option :end_date, with: :filter_by_end_date private def filter_by_min_amount(scope, value) scope.where("amount > ?", value) end def filter_by_max_amount(scope, value) scope.where("amount < ?", value) end def filter_by_start_date(scope, value) scope.where("created_at > ?", value) end
99. search = Finance::TransactionsSearch.new(filters: params[:filters]) search.results 
 search.balance
 search.income
 search.expense
 search.count
 
 search.cashier_options search.source_options search.type_options
100. , Where do all those objects live?
101. app/policies app/services app/forms app/queries
103. app/policies app/services app/forms app/queries
104. app/policies app/services app/forms app/queries app/network
105. app/policies app/services app/forms app/queries app/network app/validators
106. app/policies app/services app/forms app/queries app/network app/validators
 app/decorators
107. app/policies app/services app/forms app/queries app/network app/validators
 app/decorators app/presenters
108. app/services app/forms app/queries app/network app/validators
 app/decorators app/presenters app/notifiers
109. app/forms app/queries app/network app/validators
 app/decorators app/presenters app/notifiers app/values
110. app/queries app/network app/validators
 app/decorators app/presenters app/notifiers app/values app/support
111. app/network app/validators
 app/decorators app/presenters app/notifiers app/values app/support app/others
114. put everything in one folder put everything in one folder put every object type in its own folder
115. app/lib
 app/lib/[domain]/*.rb
 app/lib/[domain].rb
117. You only get special folder if you called in special way. Those are the special folders app/components app/controllers app/jobs app/models app/graph app/mailers
119. No JavaScript (1030 lines without any libraries)
120. require 'features_helper' feature 'Feature: Calendar' do scenario 'attendee - create > list > delete' do building = create :building sign_in_operator building account_member = create :account_member, account: building.account event = create :calendar_event, building: building visit event_path(event) click_on I18n.t(:action_new_attendee) # test: validation submit_form expect_form_errors :blank # test: create submit_form!( user_id: account_member.user_id, )
121. submit_form expect_form_errors :blank # test: create submit_form!( user_id: account_member.user_id, ) expect(page).to have_content account_member.name attendee = event.attendees.last! expect(attendee.user).to eq account_member.user # test: destroy click_on_destroy expect_flash_message :destroy expect_to_be_destroyed attendee end end
122. sign_in_operator submit_form submit_form! click_on_destroy expect_form_errors expect_flash_message expect_to_be_destroyed 5 Custom test helpers
123. Recap
124. https://tips.rstankov.com/p/my-testing-tips