Curmudgeon: An Opinionated Look at an Opinionated Framework

Rails has opinions about how we should organize code, interact with a database, write tests, format URLs... just about everything. These conventions, the wisdom goes, free us up to focus on the specifics of our application. "Convention over configuration" becomes our mantra as development hurtles forward with startling speed.

At some point, we stop. We take stock of what we've built, and it's a mess. How did we get here?

Turns out, the decisions that Rails made for us had consequences.

Transcript

1. Curmudgeon An Opinionated Look at an Opinionated Framework Ernie Miller http://erniemiller.org @erniemiller
14. curmudgeon: a person (especially an old man) who is easily annoyed or angered and who often complains Source: Merriam-Webster
19. CONVENTION OVER CONFIGURATION
20. class Convention < Opinion end
21. http://rubyonrails.org/core
22. –DHH “Rails is opinionated software.” http://www.oreillynet.com/lpt/a/6170
23. CODE SHOULD READ LIKE ENGLISH
24. 8 8.bytes 8 * 1024 8.kilobytes 8 * 1024 ** 2 8.megabytes 8 * 1024 ** 3 8.gigabytes 8 * 1024 ** 4 8.terabytes 8 * 1024 ** 5 8.petabytes 8 * 1024 ** 6 8.exabytes Time.now + 5 * 86400 5.days.from_now Time.now - 5 * 86400 5.days.ago Time.now + 14 * 86400 1.fortnight.from_now Ruby Rails
25. 8 8.bytes 8 * 1024 8.kilobytes 8 * 1024 ** 2 8.megabytes 8 * 1024 ** 3 8.gigabytes 8 * 1024 ** 4 8.terabytes 8 * 1024 ** 5 8.petabytes 8 * 1024 ** 6 8.exabytes Time.now + 5 * 86400 5.days.from_now Time.now - 5 * 86400 5.days.ago Time.now + 14 * 86400 1.fortnight.from_now Ruby Rails
26. array[2..-1] || 0 array.from(2) array.first(3) array.to(2) array[1] array.second array[2] array.third array[3] array.fourth array[4] array.fifth array << obj array.append(obj) array.unshift obj array.prepend(obj) !array.include?(obj) array.exclude?(obj) array.include?(obj) obj.in?(array) Ruby Rails
27. string.start_with?('a') string.starts_with?('a') string.end_with?('z') string.ends_with?('z') !string.include?('foo') string.exclude?('foo') env == 'production' env.production? string[0] string.first string[0..7] string.first(8) Ruby Rails
28. def beginning_of_day change(:hour => 0) end alias :midnight :beginning_of_day alias :at_midnight :beginning_of_day alias :at_beginning_of_day :beginning_of_day ! def middle_of_day change(:hour => 12) end alias :midday :middle_of_day alias :noon :middle_of_day alias :at_midday :middle_of_day alias :at_noon :middle_of_day alias :at_middle_of_day :middle_of_day active_support/core_ext/time/calculations.rb
30. coffee brewed by forcing a small amount of nearly boiling water under pressure through finely ground coffee beans
31. espresso
32. Loan words
33. MODELS DESCEND FROM ACTIVERECORD
35. rails g model
36. THE DATA IS THE DOMAIN
37. activerecord/README.rdoc “The prime directive for this mapping has been to minimize the amount of code needed to build a real-world domain model.”
38. “Lots of reflection and runtime extension” activerecord/README.rdoc
39. “Magic is not inherently a bad word.” activerecord/README.rdoc
40. CONFIGURATION IS THE DEVIL
42. class Post < ActiveRecord::Base end
43. In order to infer attribute names you must first invent the universe.
44. def inherited(child_class) child_class.initialize_generated_modules super end ! def initialize_generated_modules @generated_attribute_methods = Module.new { extend Mutex_m } @attribute_methods_generated = false include @generated_attribute_methods end active_record/attribute_methods.rb
45. def inherited(child_class) child_class.initialize_generated_modules super end ! def initialize_generated_modules @generated_attribute_methods = Module.new { extend Mutex_m } @attribute_methods_generated = false include @generated_attribute_methods end active_record/attribute_methods.rb
46. def inherited(child_class) child_class.initialize_generated_modules super end ! def initialize_generated_modules @generated_attribute_methods = Module.new { extend Mutex_m } @attribute_methods_generated = false include @generated_attribute_methods end active_record/attribute_methods.rb
47. def method_missing(method, *args, &block) self.class.define_attribute_methods if respond_to_without_attributes?(method) if attribute_method = self.class.find_generated_attribute_method(method) attribute_method.bind(self).call(*args, &block) else send(method, *args, &block) end else super end end active_record/attribute_methods.rb
48. def method_missing(method, *args, &block) self.class.define_attribute_methods if respond_to_without_attributes?(method) if attribute_method = self.class.find_generated_attribute_method(method) attribute_method.bind(self).call(*args, &block) else send(method, *args, &block) end else super end end active_record/attribute_methods.rb
49. def define_attribute_methods generated_attribute_methods.synchronize do return false if @attribute_methods_generated superclass.define_attribute_methods unless self == base_class super(column_names) @attribute_methods_generated = true end true end active_record/attribute_methods.rb
50. def define_attribute_methods generated_attribute_methods.synchronize do return false if @attribute_methods_generated superclass.define_attribute_methods unless self == base_class super(column_names) @attribute_methods_generated = true end true end active_record/attribute_methods.rb
51. def define_attribute_methods generated_attribute_methods.synchronize do return false if @attribute_methods_generated superclass.define_attribute_methods unless self == base_class super(column_names) @attribute_methods_generated = true end true end active_record/attribute_methods.rb
52. def column_names @column_names ||= columns.map { |column| column.name } end ! def columns @columns ||= connection.schema_cache.columns(table_name).map do |col| col = col.dup col.primary = (col.name == primary_key) col end end active_record/model_schema.rb
53. def column_names @column_names ||= columns.map { |column| column.name } end ! def columns @columns ||= connection.schema_cache.columns(table_name).map do |col| col = col.dup col.primary = (col.name == primary_key) col end end active_record/model_schema.rb
54. def column_names @column_names ||= columns.map { |column| column.name } end ! def columns @columns ||= connection.schema_cache.columns(table_name).map do |col| col = col.dup col.primary = (col.name == primary_key) col end end active_record/model_schema.rb
55. def table_name reset_table_name unless defined?(@table_name) @table_name end ! def reset_table_name self.table_name = if abstract_class? superclass == Base ? nil : superclass.table_name elsif superclass.abstract_class? superclass.table_name || compute_table_name else compute_table_name end end active_record/model_schema.rb
56. def table_name reset_table_name unless defined?(@table_name) @table_name end ! def reset_table_name self.table_name = if abstract_class? superclass == Base ? nil : superclass.table_name elsif superclass.abstract_class? superclass.table_name || compute_table_name else compute_table_name end end active_record/model_schema.rb
57. def table_name reset_table_name unless defined?(@table_name) @table_name end ! def reset_table_name self.table_name = if abstract_class? superclass == Base ? nil : superclass.table_name elsif superclass.abstract_class? superclass.table_name || compute_table_name else compute_table_name end end active_record/model_schema.rb
58. def compute_table_name base = base_class if self == base if parent < Base && !parent.abstract_class? contained = parent.table_name contained = contained.singularize if parent.pluralize_table_names contained += '_' end "#{full_table_name_prefix}#{contained}#{undecorated_table_name(name)}#{table_name_suffix}" else base.table_name end end active_record/model_schema.rb
59. def compute_table_name base = base_class if self == base if parent < Base && !parent.abstract_class? contained = parent.table_name contained = contained.singularize if parent.pluralize_table_names contained += '_' end "#{full_table_name_prefix}#{contained}#{undecorated_table_name(name)}#{table_name_suffix}" else base.table_name end end active_record/model_schema.rb
60. def undecorated_table_name(class_name = base_class.name) table_name = class_name.to_s.demodulize.underscore pluralize_table_names ? table_name.pluralize : table_name end active_record/model_schema.rb Conferences::RailsConf -> RailsConf -> rails_conf -> rails_confs
61. def undecorated_table_name(class_name = base_class.name) table_name = class_name.to_s.demodulize.underscore pluralize_table_names ? table_name.pluralize : table_name end active_record/model_schema.rb Conferences::RailsConf -> RailsConf -> rails_conf -> rails_confs Animals::Moose -> Moose -> moose -> mooses
62. module ActiveSupport Inflector.inflections(:en) do |inflect| inflect.plural(/$/, 's') inflect.plural(/s$/i, 's') inflect.plural(/^(ax|test)is$/i, '\1es') inflect.plural(/(octop|vir)us$/i, '\1i') inflect.plural(/(octop|vir)i$/i, '\1i') inflect.plural(/(alias|status)$/i, '\1es') inflect.plural(/(bu)s$/i, '\1ses') inflect.plural(/(buffal|tomat)o$/i, '\1oes') inflect.plural(/([ti])um$/i, '\1a') inflect.plural(/([ti])a$/i, '\1a') inflect.plural(/sis$/i, 'ses') inflect.plural(/(?:([^f])fe|([lr])f)$/i, '\1\2ves') inflect.plural(/(hive)$/i, '\1s') inflect.plural(/([^aeiouy]|qu)y$/i, '\1ies') inflect.plural(/(x|ch|ss|sh)$/i, '\1es') inflect.plural(/(matr|vert|ind)(?:ix|ex)$/i, '\1ices') inflect.plural(/^(m|l)ouse$/i, '\1ice') inflect.plural(/^(m|l)ice$/i, '\1ice') inflect.plural(/^(ox)$/i, '\1en') inflect.plural(/^(oxen)$/i, '\1') inflect.plural(/(quiz)$/i, '\1zes') ! inflect.singular(/s$/i, '') inflect.singular(/(ss)$/i, '\1') inflect.singular(/(n)ews$/i, '\1ews') inflect.singular(/([ti])a$/i, '\1um') inflect.singular(/((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)(sis|ses)$/i, '\1sis') inflect.singular(/(^analy)(sis|ses)$/i, '\1sis') inflect.singular(/([^f])ves$/i, '\1fe') active_support/inflections.rb
63. inflect.singular(/(s)eries$/i, '\1eries') inflect.singular(/(m)ovies$/i, '\1ovie') inflect.singular(/(x|ch|ss|sh)es$/i, '\1') inflect.singular(/^(m|l)ice$/i, '\1ouse') inflect.singular(/(bus)(es)?$/i, '\1') inflect.singular(/(o)es$/i, '\1') inflect.singular(/(shoe)s$/i, '\1') inflect.singular(/(cris|test)(is|es)$/i, '\1is') inflect.singular(/^(a)x[ie]s$/i, '\1xis') inflect.singular(/(octop|vir)(us|i)$/i, '\1us') inflect.singular(/(alias|status)(es)?$/i, '\1') inflect.singular(/^(ox)en/i, '\1') inflect.singular(/(vert|ind)ices$/i, '\1ex') inflect.singular(/(matr)ices$/i, '\1ix') inflect.singular(/(quiz)zes$/i, '\1') inflect.singular(/(database)s$/i, '\1') ! inflect.irregular('person', 'people') inflect.irregular('man', 'men') inflect.irregular('child', 'children') inflect.irregular('sex', 'sexes') inflect.irregular('move', 'moves') inflect.irregular('zombie', 'zombies') ! inflect.uncountable(%w(equipment information rice money species series fish sheep jeans police)) end end active_support/inflections.rb
64. ActiveSupport::Inflector.inflections(:en) do |inflect| inflect.uncountable 'moose' end config/initializers/inflections.rb
65. CONFIGURATION
66. class Moose < ActiveRecord::Base self.table_name = 'moose' end app/models/moose.rb
67. CONFIGURATION
71. class Post < ImaginaryRecord::Record self.table_name 'posts' ! attribute :id, Attr::Integer attribute :title, Attr::String attribute :body, Attr::String attribute :created_at, Attr::Timestamp attribute :updated_at, Attr::Timestamp end in/your/imagination.rb
72. class MagicRecord < ImaginaryRecord::Record def method_missing(method, *args, &block) self.class.define_attribute_methods # ... end ! def self.define_attribute_methods # ... klass.table_name(compute_table_name) columns_from_table(table_name).each do |column| klass.attribute column.name, column.type end # ... end end in/your/imagination.rb
73. class Post < MagicRecord end
74. ActiveRecord
75. ActiveRecord Attribute typecasting Serialization Macro reflection Transactions Nested attributes Associations Secure passwords Timestamps Lifecycle callbacks Dirty tracking Validations Mass assignment sanitation
76. ActiveRecord Attribute typecasting Serialization Macro reflection Transactions Nested attributes Associations Secure passwords Timestamps Lifecycle callbacks Dirty tracking Validations Mass assignment sanitation Querying Persisting
77. MyModel #<Module:0x007fc42ad68878> ActiveRecord::Base ActiveRecord::Store ActiveRecord::Serialization ActiveModel::Serializers::Xml ActiveModel::Serializers::JSON ActiveModel::Serialization ActiveRecord::Reflection ActiveRecord::Transactions ActiveRecord::Aggregations ActiveRecord::NestedAttributes ActiveRecord::AutosaveAssociation ActiveModel::SecurePassword ActiveRecord::Associations ActiveRecord::Timestamp ActiveModel::Validations::Callbacks
78. ActiveModel::Conversion ActiveRecord::AttributeAssignment ActiveModel::ForbiddenAttributesProtection ActiveRecord::Sanitization ActiveRecord::Scoping::Named ActiveRecord::Scoping::Default ActiveRecord::Scoping ActiveRecord::Inheritance ActiveRecord::ModelSchema ActiveRecord::ReadonlyAttributes ActiveRecord::NoTouching ActiveRecord::Persistence ActiveRecord::Core Object ActiveSupport::Dependencies::Loadable JSON::Ext::Generator::GeneratorMethods::Object Kernel BasicObject
79. ActiveModel::Conversion ActiveRecord::AttributeAssignment ActiveModel::ForbiddenAttributesProtection ActiveRecord::Sanitization ActiveRecord::Scoping::Named ActiveRecord::Scoping::Default ActiveRecord::Scoping ActiveRecord::Inheritance ActiveRecord::ModelSchema ActiveRecord::ReadonlyAttributes ActiveRecord::NoTouching ActiveRecord::Persistence ActiveRecord::Core Object ActiveSupport::Dependencies::Loadable JSON::Ext::Generator::GeneratorMethods::Object Kernel BasicObject Clarity
80. API SURFACE AREA IS IRRELEVANT
81. Single Responsibility Principle Simple, for sufficiently large values of “responsibility.”
82. Class.new (2.1.1) Model View Controller Ancestors 4 56 50 63 Public/ Protected Methods 99 575 244 351 Private Methods 90 126 101 105 Public/ Protected Methods 55 311 405 333 Private Methods 72 160 132 115 Class Instance
84. https://github.com/ernie/curmudgeon
85. Helpers
86. module PostsHelper def summary(post) # excerpt and tags end end ! module ReviewsHelper def summary(review) # number of stars and excerpt end end
87. <h1> <%= summarizable.title %> </h1> <p> <%= summary(summarizable) %> </p> app/views/shared/_summarizable_with_summary.html.erb
88. Development: ✔️
89. Production:
90. Production:❓
94. module Curmudgeon class Application < Rails::Application config.action_controller.include_all_helpers = false end end config/application.rb
101. WHO NEEDS CLASSES WHEN WE’VE GOT MODULES?
102. module Foo def self.included(base) base.class_eval do def self.method_injected_by_foo ... end end end end ! module Bar def self.included(base) base.method_injected_by_foo end end ! class Host include Foo # We need to include this dependency for Bar include Bar # Bar is the module that Host really needs end
103. require 'active_support/concern' ! module Foo extend ActiveSupport::Concern included do def self.method_injected_by_foo ... end end end ! module Bar extend ActiveSupport::Concern include Foo ! included do self.method_injected_by_foo end end ! class Host include Bar # works, Bar takes care now of its dependencies end
105. +
107. RUBY VIRTUAL ^
109. You
110. You
111. YOUR CONVENTIONS SUCK
112. JavaScript
113. page.replace_html('tasks-completed', Task.completed_count) page.replace_html('tasks-remaining', Task.remaining_count) page.replace_html( 'task-status-' + @task.id.to_s, @task.status.description ) page.visual_effect( :highlight, 'task-item-' + @task.id.to_s, :duration => 1.0 ) app/views/task/_update_tasks.rjs RJS
114. unless Array::filter Array::filter = (callback) -> element for element in this when callback(element) ! array = [1..10] ! filtered_array = array.filter (x) -> x % 2 == 0 ! gt_five = (x) -> x > 5 filtered_array = array.filter gt_five CoffeeScript
115. <script type="text/javascript"> $(function() { // ... }); </script>
116. Turbolinks “With Turbolinks pages will change without a full reload, so you can't rely on DOMContentLoaded or jQuery.ready() to trigger your code.” — Turbolinks README
117. Data Integrity
118. class Order < ActiveRecord::Base belongs_to :customer has_many :line_items, :dependent => :destroy ! validates :customer, :presence => true validates :refnum, :uniqueness => true validates_associated :line_items end
120. SYSTEM
121. MANAGEMENT SYSTEM
122. RELATIONAL MANAGEMENT SYSTEM
123. RELATIONAL DATABASE MANAGEMENT SYSTEM
126. IDD
127. IGNORANCE-DRIVEN DEVELOPMENT Blissful.
128. START WITH RUBY Ignore persistence, for now.
129. IDENTIFY THE SCARY THINGS What are you afraid you can’t write?
130. ATTACK THE SCARY THINGS (With tests. Preferably sharp and pointy tests.)
131. describe Monster do let(:teeth) { nil } let(:claws) { nil } subject { Monster.new(teeth, claws) } ! describe 'with no teeth or claws' do it 'cannot bite' do proc { subject.bite('Ernie') }.must_raise NoMethodError end ! it 'cannot scratch' do proc { subject.bite('Ernie') }.must_raise NoMethodError end end end class Monster def initialize(teeth = nil, claws = nil) @teeth, @claws = teeth, claws end ! def bite(target) @teeth.bite(target) end ! def scratch(target) @claws.scratch(target) end end
132. SLAY THE SCARY THINGS
133. ADMIT PERSISTENCE
134. class Monster < ActiveRecord::Base belongs_to :teeth belongs_to :claws validates :teeth, :claws, :presence => true end
135. USE MODULES
137. class Monster < ActiveRecord::Base include ::Monster::Biting include ::Monster::Scratching ! belongs_to :teeth belongs_to :claws validates :teeth, :claws, :presence => true end
138. class Monster < ActiveRecord::Base module Biting def bite(target) target.punctured!(teeth.damage_roll) end end end app/behaviors/monster/biting.rb
139. describe 'Monster::Biting' do let(:biter) { Class.new { attr_reader :teeth include ::Monster::Biting def initialize(teeth) @teeth = teeth end } } ! it ‘inflicts puncture damage' do # ... end end spec/behaviors/monster/biting_spec.rb
140. CONCERNED?
141. Monster Biting Scratching Fighting
142. Monster Biting Scratching Fighting
143. Monster Biting Scratching Fighting
144. Monster Biting Scratching Encounter class Encounter def initialize(*combatants) @combatants = combatants end ! # ... end
145. MVP
146. The art of writing software is getting the desired result while making the fewest decisions possible.
147. START WITH FEWER OPINIONS
148. START WITH FEWER ASSUMPTIONS
149. BUILD FLOORS WITH A PURPOSE
150. BE A CONSIDERATE SOFTWARE WRITER
151. THANKS! Ernie Miller http://erniemiller.org @erniemiller
152. ❤️ THANKS! Ernie Miller http://erniemiller.org @erniemiller