Rails 5 deprecations and changes

• Ruby version ruby '2.6.0'
• The :nothing option for the render method is deprecated., please use head: :ok instead

Deprecated

def index
    render :nothing
end

Use

def index
   head: :ok
end

• The *_filter methods (before_filter, for example) are still supported, but deprecated and will be removed in Rails 5.1. Use *_action instead.

• A nice method redirect_back is being introduced in favor of redirect_to :back. It tries to redirect to an HTTP_REFERER or to the provided location, so you may use it inside your methods:

• render :text is deprecated, as it does not render a text/plain response. Use render :plain instead or render :html to display a text/html page:

• The respond_to and respond_with methods have been extracted to the responders gem, so be sure to include it in the Gemfile if you use those methods.

• Rails 5 has introduced models/application_record.rb

class ApplicationRecord < ActiveRecord::Base
  self.abstract_class = true
end

Use case:-

class User < ApplicationRecord
  [...]
end

• Belongs to must have optional: true if its optional

belongs_to :some_parent, optional: true

• rails 5 has introduced migration version

Example use case:-

class CreateApps < ActiveRecord::Migration[4.2]
  def change
    create_table :apps do |t|
      t.text :app_type
      t.text :content
      t.integer :user_id
      t.boolean :saved
      t.timestamps
    end
  end
end