Description

This cookbook is designed to be able to describe and deploy Ruby web applications. Currently supported:

• Ruby on Rails
• Apache 2 with Passenger
• Unicorn
• Memcached client

Note that this cookbook provides the Ruby-specific bindings for the application cookbook; you will find general documentation in that cookbook.

Other application stacks may be supported at a later date.

Requirements

Chef 0.10.0 or higher required (for Chef environment use).

The following Opscode cookbooks are dependencies:

• application
• apache2
• passenger_apache2
• runit
• unicorn

Resources/Providers

The LWRPs provided by this cookbook are not meant to be used by themselves; make sure you are familiar with the application cookbook before proceeding.

rails

The rails sub-resource LWRP deals with deploying Ruby on Rails webapps from an SCM repository. It uses the deploy_revision LWRP to perform the bulk of its tasks, and many concepts and parameters map directly to it. Check the documentation for deploy_revision for more information.

For applications that use Bundler, if a Gemfile.lock is present then gems will be installed with bundle install --deployment, which results in gems being installed inside the application directory.

When running Bundler, unnecessary groups will be skipped. The list of groups to skip is determined with this algorithm:

• start with this Array: development test cucumber staging production;
• the group corresponding to the current environment will be removed from the Array;
• if the bundler_without_groups attribute is set, those groups will be added to the Array.

For example, for a node running in the production Chef environment, and given:

bundler_without_groups ["mysql"]

Bundler will be run with:

bundle install --without development test cucumber staging mysql

Attribute Parameters

• gems: an Array of gems to install
• bundler: if true, bundler will always be used; if false it will never be. Defaults to true if gems includes bundler
• bundle_command: The command to execute when calling bundler commands. Useful for specifing alternate commands such as RVM wrappers. Defaults to bundle.
• bundler_deployment: if true, Bundler will be run with the --deployment options. Defaults to true if a Gemfile.lock is present
• bundler_without_groups: an Array of additional Bundler groups to skip
• database_master_role: if a role name is provided, a Chef search will be run to find a node with than role in the same environment as the current role. If a node is found, its IP address will be used when rendering the database.yml file, but see the "Database block parameters" section below
• database_template: the name of the template that will be rendered to create the database.yml file; if specified it will be looked up in the application cookbook. Defaults to "database.yml.erb" from this cookbook
• database: a block containing additional parameters for configuring the database connection
• precompile_assets: if true, precompile assets for the Rails 3 asset pipeline. The default is nil, in which case we will try to autodetect whether the pipeline is in use by looking for config/assets.yml

Database and memcached block parameters

The database and memcached blocks can accept any method, which will result in an entry being created in the @database and @memcached_envs Hashes which are passed to the respective templates. See Usage below for more information.

passenger_apache2

The passenger_apache2 sub-resource LWRP configures Apache 2 with Passenger to run the application.

Attribute Parameters

• server_aliases: an Array of server aliases
• webapp_template: the template to render to create the virtual host configuration. Defaults to "#{application name}.conf.erb"
• params: an Hash of extra parameters that will be passed to the template

unicorn

The unicorn sub-resource LWRP configures Unicorn to run the application.

Attribute Parameters

• bundler: if true, Unicorn will be run with bundle exec; if false it will be installed and run from the default gem path. Defaults to inheriting this setting from the rails LWRP
• preload_app: passed to the unicorn_config LWRP
• worker_processes: passed to the unicorn_config LWRP
• before_fork: passed to the unicorn_config LWRP
• port: passed to the unicorn_config LWRP
• worker_timeout: passed to the unicorn_config LWRP

memcached

The memcached sub-resource LWRP manages configuration for a Rails-compatible Memcached client.

Attribute Parameters

• role: a Chef search will be run to find a node with than role in the same environment as the current node. If a node is found, its IP address will be used when rendering the memcached.yml file.
• options: a block containing additional parameters for configuring the memcached client

Usage

A sample application that needs a database connection:

application "redmine" do
  path "/usr/local/www/redmine"

  rails do 
    database do
      database "redmine"
      username "redmine"
      password "awesome_password"
    end
    database_master_role "redmine_database_master"
  end

  passenger_apache2 do
  end
end

You can invoke any method on the database block:

application "my-app" do
  path "..."
  repository "..."
  revision "..."

  rails do
    database_master_role "my-app_database_master"
    database do
      database 'name'
      quorum 2
      replicas %w[Huey Dewey Louie]
    end
  end
end

The corresponding entries will be passed to the context template:

<%= @database['quorum'] %>
<%= @database['replicas'].join(',') %>

A sample application that connects to memcached:

application "my-app" do
  path "..."
  repository "..."
  revision "..."

  memcached do
    role "memcached_master"
    options do
      ttl 1800
      memory 256
    end
  end
end

This will generate a config/memcached.yml file:

production:
  ttl: 1800
  memory: 256
  servers:
    - 192.168.0.10:11211

License and Author

Author:: Adam Jacob (adam@opscode.com) Author:: Andrea Campi (andrea.campi@zephirworks.com.com) Author:: Joshua Timberman (joshua@opscode.com) Author:: Seth Chisamore (schisamo@opscode.com)

Copyright 2009-2012, Opscode, Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.