I first encountered the "solid queue" gem when it was announced to be shipped with Rails 8 as the default active job backend.

It is DB-based and compatible with Rails multi-threading. The debugging of active job issues is simpler with its enhanced logging and queue data persisted in the database.

Since Rails 8 is currently under development, I decided to try it with a Rails 7 application.

Setup

It is plug-and-play, with 3 simple steps below.

1) Install the gem

gem "solid_queue"

2) Install and run its migration

$ rails solid_queue:install:migrations
$ rails db:migrate

3) Update queue adapter in configuration

config.active_job.queue_adapter = :solid_queue

4) To test it, you can run this command

$ bundle exec rake solid_queue:start

Using it in Production

1) There are many ways to manage the solid queue processes. I choose to use supervisor on a Ubuntu server.

$ sudo apt update && sudo apt install supervisor

2) This can be done by creating a configuration file

$ sudo pico /etc/supervisor/conf.d/rails-solid-queue.conf

[program:rails-solid-queue]
process_name=%(program_name)s_%(process_num)02d
directory=/path/to/app
command=/path/to/bundle exec rake solid_queue:start
environment=RAILS_ENV=production
autostart=true
autorestart=true
stopasgroup=true
killasgroup=true
user=user
numprocs=1
redirect_stderr=true
stdout_logfile=/path/to/log
stopwaitsecs=3600

3) Then load and start the configuration

$ sudo supervisorctl reread
$ sudo supervisorctl update

Integrate it with the Capistrano deployment

1) I use Capistrano to deploy the demo app. So the supervisor-monitored processes must be restarted when I deploy new codes.

2) The following codes are added in my deploy.rb to perform the restart after the deployment.

# etc

# restart supervisor
namespace :deploy do
  desc 'Restart supervisor rails-solid-queue'
  task :restart_application do
    on roles(:app) do
      execute :sudo, 'supervisorctl restart rails-solid-queue:*'
    end
  end

  after :finished, :restart_application
end

3) That is all the setup needed to deploy Solid Queue in production.