zammad/config/initializers/action_cable_preferences.rb

# Copyright (C) 2012-2021 Zammad Foundation, http://zammad-foundation.org/

if ENV['REDIS_URL'].present?
  Rails.application.config.action_cable.cable = {
    'adapter'        => 'redis',
    'url'            => ENV['REDIS_URL'],
    'channel_prefix' => "zammad_#{Rails.env}"
  }
  Rails.logger.info 'Using the Redis adapter for ActionCable.'
else
  if ActiveRecord::Base.connection_config[:adapter] == 'mysql'
    raise 'Please provide a working redis instance via REDIS_URL - this is required on MySQL databases.'
  end

  Rails.application.config.action_cable.cable = {
    'adapter' => 'postgresql',
  }
  Rails.logger.info 'Using the PostgreSQL adapter for ActionCable.'
end