ekuzovlev

class AddRoleToUsers < ActiveRecord::Migration[7.2]
  def up
    execute <<-SQL
      DO $$
      BEGIN
        IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'user_role') THEN
          CREATE TYPE user_role AS ENUM ('user', 'admin');
        END IF;
      END
      $$;

ekuzovlev

This was my solution for a polymorphic many-to-many association

class ItemCountry < ActiveRecord::Base
  belongs_to :locatable, :polymorphic => true
  belongs_to :country
  # fields are :locatable_id, :locatable_type, :country_id
end

class Title < ActiveRecord::Base

has_many :countries, :through => :item_countries, :as => :locatable

ekuzovlev

How to deploy a Rails 7.1 app with Postgres and Kamal on a single server

I think you have looked at the tutorial from Mr. Heinemeier Hansson at least once or twice and have a similar setup.

rails new kamal_pg --css tailwind --skip-test --database=postgresql

cd kamal_pg

ekuzovlev

JWT Auth + Refresh Tokens in Rails

This is just some code I recently used in my development application in order to add token-based authentication for my api-only rails app. The api-client was to be consumed by a mobile application, so I needed an authentication solution that would keep the user logged in indefinetly and the only way to do this was either using refresh tokens or sliding sessions.

I also needed a way to both blacklist and whitelist tokens based on a unique identifier (jti)

Before trying it out DIY, I considered using:

ekuzovlev

Byebug Cheatsheet

This cheatsheet includes most of the byebug commands organized by related commands (e.g. breakpoint related commands are together).

To see official help...

Command	Aliases	Example	Comments
help	h	h	list top level of all commands
help cmd	h cmd-alias	h n	list the details of a command (example shows requesting details for the next command) (this works for all commands)

ekuzovlev

# controller.rb
# parsing errors from response
errors = Nokogiri::XML(response.body).css('Error').map(&:text)

# add errors to model.errors
errors.each do |err|
  @test.errors.add :base, :invalid, message: err
end

# partials/_error.html.erb

ekuzovlev

From https://github.com/philsmy/cable-guy-example/blob/1ad67e6e929a9f4a4d6357c5283a36aef8c6debc/SetUpServer.txt
# set up user
ssh root@yourserverip
adduser deploy
adduser deploy sudo
vi /etc/ssh/sshd_config
enable PasswordAuthentication
save
systemctl restart sshd
exit

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Перезагрузка приложения

passenger-config restart-app

Перезагрузка Nginx

service nginx restart

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error: Your local changes to the following files would be overwritten by merge: Please commit your changes or stash them before you merge.

git checkout file/to/overwrite
git pull

ekuzovlev

Rails Migration

http://guides.rubyonrails.org/migrations.html

Migrations methods:

• add_column
• add_index
• change_column
• change_table
• create_table
• drop_table