Rails Best Practices

Comprehensive guide to Rails best practices for clean, maintainable code.

Models

Keep models skinny. Business logic belongs in service objects.
Use scopes for common queries.
Validate data integrity with model validations.

# Example Scope
class User < ApplicationRecord
  scope :active, -> { where(status: 'active') }

  validates :email, presence: true, uniqueness: true
end

Controllers

Keep controllers skinny. Delegate complex logic to service objects or helpers.
Use strong parameters for mass assignment protection.

# Example Controller
class UsersController < ApplicationController
  def create
    @user = User.new(user_params)

    if @user.save
      redirect_to @user, notice: 'User was successfully created.'
    else
      render :new
    end
  end

  private

  def user_params
    params.require(:user).permit(:email, :password, :name)
  end
end

Views

Keep views simple. Avoid embedding logic in views.
Use partials for reusable components.

# Example Partial (_user.html.erb)

  <%= user.name %>
  <%= user.email %>

Routes

Use RESTful routes for resourceful controllers.
Group related routes with `namespace` and `scope`.

# Example Routes
Rails.application.routes.draw do
  resources :users
  namespace :admin do
    resources :reports
  end
end

Migrations

Use descriptive names for migrations.
Always include `up` and `down` methods for reversible migrations.

# Example Migration
class CreateUsers < ActiveRecord::Migration[6.1]
  def change
    create_table :users do |t|
      t.string :email, null: false
      t.string :name
      t.timestamps
    end
  end
end

Testing

Write unit tests for models and service objects.
Write system tests for controllers and views.

# Example RSpec Test
RSpec.describe User, type: :model do
  it { should validate_presence_of(:email) }
end