Capistrano::Cable

Capistrano::Cable helps to deploy standalone ActionCable server with Puma over systemd. It doesn't use a specific puma.rb for Puma configuration, it relies on given options.

Install the gem and add to the application's Gemfile by executing:

$ bundle add capistrano-cable

If bundler is not being used to manage dependencies, install the gem by executing:

$ gem install capistrano-cable

# Capfile

require 'capistrano/cable'
install_plugin Capistrano::Cable::Systemd

To prevent loading the hooks of the plugin, add false to the load_hooks param.

# Capfile

install_plugin Capistrano::Cable, load_hooks: false  # Default cable tasks without hooks

To make it work with rvm, rbenv and chruby, install the plugin after corresponding library inclusion.

# Capfile

require 'capistrano/rbenv'
require 'capistrano/cable'
install_plugin Capistrano::Cable

Many options are available to customize the cable server configuration. Here are the main ones:

# config/deploy.rb or config/deploy/<stage>.rb
set :cable_role, :web
set :cable_port, 29292
# set :cable_limit_nofile, 65536 # optional, to customize if `Errno::EMFILE: Too many open files` happens
# set :cable_ssl_certificate
# set :cable_ssl_certificate_key
set :cable_rackup_file, 'cable/config.ru'
set :cable_dir, -> { File.join(release_path, "cable") }
set :cable_pidfile, -> { File.join(shared_path, "tmp", "pids", "cable.pid") }
set :cable_env, -> { fetch(:rack_env, fetch(:rails_env, fetch(:stage))) }
set :cable_access_log, -> { File.join(shared_path, "log", "cable.access.log") }
set :cable_error_log, -> { File.join(shared_path, "log", "cable.error.log") }
set :cable_phased_restart, -> { true }
set :cable_service_unit_env_files, -> { fetch(:service_unit_env_files, []) }
set :cable_service_unit_env_vars, -> { fetch(:service_unit_env_vars, []) }
set :cable_service_templates_path, fetch(:service_templates_path, "config/deploy/templates")

See Capistrao::Cable::Systemd#set_defaults for more details.

To enable SSL, set the cable_ssl_certificate and cable_ssl_certificate_key options. The both are required to enable SSL.

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/codeur/capistrano-cable. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

Largely inspired from capistrano-puma gem.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the Capistrano::Cable project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.