Capistrano Unicorn

Capistrano 3.x plugin that integrates Unicorn tasks into capistrano deployment script. Taken from https://github.com/sosedoff/capistrano-unicorn and adapted to work with Capistrano 3.x.

Add the library to your Gemfile:

group :development do
  gem 'glebtv-capistrano-unicorn', :require => false
end

Add it to Capfile:

require 'capistrano/unicorn'

Add unicorn restart task hook:

If your app IS NOT preloaded (preload_app false, default):

after 'deploy:publishing', 'unicorn:reload'

If your app is preloaded (preload_app true):

after 'deploy:publishing', 'unicorn:restart'

If you have before_fork unicorn hook for zero downtime deployments installed (preload_app true + before_hook), best option:

after 'deploy:publishing', 'unicorn:duplicate'

Create a new configuration file config/unicorn.rb or config/unicorn/STAGE.rb, where stage is your deployment environment.

Includes zero-downtime deployments

examples/rails3.rb.

Please READ all comments in the file if you are having problems. If you use AR you need to uncomment two lines in the file.

Please refer to Unicorn documentation for more examples and configuration options.

First, make sure you're running the latest release:

cap production deploy

Then you can test each individual task:

cap production unicorn:start
cap production unicorn:stop
cap production unicorn:reload

You can modify any of the following Capistrano variables in your deploy.rb config. You can use the unicorn:show_vars task to check that the values you have specified are set correctly.

• unicorn_env - Set basename of unicorn config .rb file to be used loaded from unicorn_config_path. Defaults to rails_env variable if set, otherwise production.
• unicorn_rack_env - Set the value which will be passed to unicorn via the -E parameter as the Rack environment. Valid values are development, deployment, and none. Defaults to development if rails_env is development, otherwise deployment.

• unicorn_user - Launch unicorn master as the specified user via sudo. Defaults to nil, which means no use of sudo, i.e. run as the user defined by the user variable.
• unicorn_roles - Define which roles to perform unicorn recipes on. Defaults to :app.
• unicorn_bundle - Set bundler command for unicorn. Defaults to bundle.
• unicorn_bin - Set unicorn executable file. Defaults to unicorn.
• unicorn_options - Set any additional options to be passed to unicorn on startup.
• unicorn_restart_sleep_time - Number of seconds to wait for (old) pidfile to show up when restarting unicorn. Defaults to 2.

• app_subdir - If your app lives in a subdirectory 'rails' (say) of your repository, set this to /rails (the leading slash is required).
• unicorn_config_rel_path - Set the directory path (relative to app_path - see below) where unicorn config files reside. Defaults to config.
• unicorn_config_filename - Set the filename of the unicorn config file loaded from unicorn_config_path. Should not be present in multistage installations. Defaults to unicorn.rb.

• app_path - Set path to app root. Defaults to current_path + app_subdir.
• unicorn_pid - Set unicorn PID file path. By default, attempts to auto-detect from unicorn config file. On failure, falls back to value in unicorn_default_pid
• unicorn_default_pid - See above. Defaults to #{current_path}/tmp/pids/unicorn.pid
• bundle_gemfile - Set path to Gemfile. Defaults to #{app_path}/Gemfile
• unicorn_config_path - Set the directory where unicorn config files reside. Defaults to #{current_path}/config.

• unicorn:restart: 👎 This can sort of support it with a configurable timeout, which may not be reliable.
• unicorn:reload: ❓ Can anyone testify to its zero-downtime support?
• unicorn:duplicate: 👍 If you install the Unicorn before_fork hook, then yes! See: sosedoff#40 (comment)

To get a list of all capistrano tasks, run cap -T:

cap production unicorn:add_worker                # Add a new worker
cap production unicorn:remove_worker             # Remove amount of workers
cap production unicorn:reload                    # Reload Unicorn
cap production unicorn:restart                   # Restart Unicorn
cap production unicorn:show_vars                 # Debug Unicorn variables
cap production unicorn:shutdown                  # Immediately shutdown Unicorn
cap production unicorn:start                     # Start Unicorn master process
cap production unicorn:stop                      # Stop Unicorn

See LICENSE file for details.