Using heroku 22 stack

2022-07-07 ruby rails

Since heroku-18 support will end soon(ended?), needed to update to latest heroku-22.

The big problem is it only supports Ruby 3.1. However, our system was working on Ruby 2.7 and Rails 5. To updating Ruby version(2.7 -> 3.1), also needed to update rails gem(5.2 -> 6.1). Then also required to add the following gems in Gemfile.

gem 'net-imap', '~> 0.2'
gem 'net-pop', '~> 0.1'
gem 'net-smtp', '~> 0.3'

In addition(if you are using activerecord), may need to update database tables related to activerecord.

rails active_storage:update
rails db:migrate