/capistrano-unicorn-nginx-ami

Capistrano tasks for automatic and sensible unicorn + nginx configuration

Primary LanguageRubyMIT LicenseMIT

This Fork

This fork provides specific adjustments to work with Amazon Linux (which in turn is Redhat-based).

This means that some commands are different:

  • using chkconfig instead of update-rc.d
  • assuming nginx is installed and available at /etc/nginx
  • assuming configuration for nginx lives at /etc/conf.d/[ENV_NAME].conf

All credit to irlrobot.

NOTE: This fork has different version numbers!

Since I made this fork, in order to use the release pages on github, I decided to move forward and put new version numbers.

So beware that version numbers differ from v4.0.0 and onwards.

unicorn:restart vs unicorn:upgrade

For backwards compatibility, this plugin will run sudo service unicorn restart, which reloads processes but doesn't pick up code changes.

Typically you would want to use unicorn:upgrade instead (picks up code changes).

put the following snippet in your deploy.rb:

# clear originating task before replacing it
Rake::Task['unicorn:restart_command'].clear_actions
namespace :unicorn do
  task :restart_command do
    invoke 'unicorn:upgrade'
  end
end

Capistrano::UnicornNginx

NOTE: The instructions below are no longer necessary from version 4.1.0. The dhparam file will be automatically generated if missing.

IMPORTANT NOTE. When upgrading to 4.0.0, please ensure you have generated a new 2048 bits Diffie-Hellman group. Run the following command on your server before installing this gem:

openssl dhparam -out /etc/nginx/ssl/dhparam.pem 2048

See https://weakdh.org/sysadmin.html for more details.

Capistrano tasks for automatic and sensible unicorn + nginx configuraion.

Goals of this plugin:

  • automatic unicorn and nginx configuration for Rails apps
  • no manual ssh to the server required
  • zero downtime deployments enabled
  • support for single node as well as cluster deployments

Specifics:

  • generates nginx config file on the server (web role)
  • generates unicorn initializer and config files (app role)
    application is started automatically after server restart
  • capistrano tasks for server management, example: unicorn:restart
    see below for all available tasks
  • automatic load balancing setup when there are multiple app nodes

capistrano-unicorn-nginx works only with Capistrano 3!

Installation

Add this to Gemfile:

group :development do
  gem 'capistrano', '~> 3.6.1'
  gem 'capistrano-unicorn-nginx', '~> 4.1.0'
end

And then:

$ bundle install

Setup and usage

Depending on your needs 2 general scenarios are covered:

  • single server setup
    A scenario where you run the webserver (nginx) and application server (unicorn) on the same node.
  • multiple server setup
    Webserver (nginx) and application server (unicorn) run on different nodes.

Ubuntu 16.04

In order for current version to work you need upstart installed instead of systemd.

sudo apt-get install upstart-sysv package

This commando should remove ubuntu-standard and systemd-sysv.

After that go ahead and run sudo update-initramfs -u.

Default log file directories

  • nginx: /var/log/nginx/
  • unicorn: #{shared_path}/log/

Configuration

See the full options list on the wiki page. Feel free to skip this unless you're looking for something specific.

How it works

How it works wiki page contains the list of tasks that the plugin executes.

You do not have to know this unless you want to learn more about the plugin internals.

Template customization

On template customization wiki page see how to inspect, tweak and override templates for nginx and unicorn config files.

Do not do this unless you have a specific need.

More Capistrano automation?

Check out capistrano-plugins github org.

Bug reports and pull requests

...are very welcome!

Thanks

@kalys - for his capistrano-nginx-unicorn plugin.