ccyrille

# Service module
#
# Example usage :
# ```
#   class SayHello
#     include Service
#
#     attr_accessor :name
#
#     def call

ccyrille

Klaxit

Klaxit est une plateforme d’action pour révolutionner la mobilité quotidienne grâce au covoiturage domicile-travail. C’est l’application #1 du covoiturage courte distance, avec plus de 300 entreprises clientes dont la moitié des sociétés du CAC40 et 30 collectivités locales partenaires.

Mission

Votre mission sera de prendre la responsabilité d’une équipe de 3-5 développeurs :

ccyrille

How to keep it clean, for years

Paris.rb 2020, Cyrille Courtière, CTO @Klaxit

https://github.com/klaxit

Presentation slides

You will find here a full version of my presentation (including things I said but didn't write during my talk) :

ccyrille

# Module used to build a service.
#
# Example usage :
# ```
#   class SayHello
#     include Service
#     attr_accessor :name
#
#     def call
#       puts "Hello #{name} !"

ccyrille

# This module allows to have an after_commit callback
# on a single AR instance. This is really useful in services.
#
# Usage example :
#   mate = Mate.first
#   mate.after_commit { |m| notify_first_name_changed(m) }
#   mate.update_attributes!(first_name: "Gunter")
#
module ActiveRecord::InstanceCallbacks
  def has_transactional_callbacks?

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class AddIndexToUsersOnName < ActiveRecord::Migration
  disable_ddl_transaction!
  
  def change
    add_index :users, :name, algorithm: :concurrently
  end
end

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class User < ActiveRecord::Base
...
  # << REMOVE ON NEXT RELEASE
  def new_column
    read_attribute(:new_column) if has_attribute?(:new_column)
  end
  
  def new_column=(value)
    write_attribute(:new_column, value) if has_attribute?(:new_column)
  end

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class ChangeUsersNewColumnNull < ActiveRecord::Migration
  def change
    change_column_null :users, :new_column, false
  end
end

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class PopulateUsersNewColumnDefaultValue < ActiveRecord::Migration
  disable_ddl_transaction!
  
  def up
    User.find_in_batches do |users|
      User.where(id: users.map(&:id), new_column: nil)
          .update_all(new_column: "default_value")
    end  
  end  
end

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class AddNewColumnToUsers < ActiveRecord::Base
  def change
    add_column :users, :new_column, :text
  end
end