Our myapp defined type will make use of the db resource we created in the previous section, passing four values to PuppetDB, directly from myapp::db. We'll use this manifest to build a MySQL server, and provide information to our WordPress instance on another node. Notice the following in the example:

• A regular defined type, with standard Puppet DSL. We build a server and a database to support the app.
• $host is not used in the manifest, but is passed along to the produced Db resource.
• Myapp::Db produces Db is placed directly after the define, in the same manifest:

define myapp::db (
  $dbuser,
  $dbpass,
  $host = $::fqdn,
){

  class {'::mysql::server':
    root_password => 'Sup3rp@ssword!',
    override_options => {
      'mysqld' => {
        'bind-address' => '0.0.0.0'
      }
    }
  }

  mysql::db { $name:
    user => $dbuser,
    password => $dbpass,
    host => '%',
    grant => ['ALL PRIVILEGES'],
  }
}
Myapp::Db produces Db {
  dbuser => $dbuser,
  dbpass => $dbpass,
  dbhost => $host,
  dbname => $name,
}

Myapp::Web is a defined type meant to consume the Db produced by Myapp::Db. It installs the required packages, installs Apache, builds a vhost, and deploys WordPress to the docroot of the vhost. Notice the following:

• $vhost and $webpath were provided by application myapp.
• $dbuser, $dbpass, $dbhost, and $dbname are provided by the consumes Db {}.
• Because our manifest uses the values dbpass, dbhost, dbuser and dbname, our mappings don't need to be declared. The following example will directly declare variables:

define myapp::web (
  $webpath,
  $vhost,
  $dbuser,
  $dbpass,
  $dbhost,
  $dbname,
  ) {

    package {['php',
              'mysql',
              'php-mysql',
              'php-gd'
             ]:
      ensure => installed,
    }

    class {'apache':
      default_vhost => false
    }

    include ::apache::mod::php

    apache::vhost { $vhost:
      port => '80',
      docroot => $webpath,
      require => File[$webpath],
    }

    file { $webpath:
      ensure => directory,
      owner => 'apache',
      group => 'apache',
      require => Package['httpd'],
    }

    class { '::wordpress':
      db_user => $dbuser,
      db_password => $dbpass,
      db_host => $dbhost,
      db_name => $dbname,
      create_db => false,
      create_db_user => false,
      install_dir => $webpath,
      wp_owner => 'apache',
      wp_group => 'apache',
    }
  }
Myapp::Web consumes Db { }

We can use the preceding collection of code to order and deploy our multitier application. Our current module should resemble the following:

myapp
├── lib
│   └── puppet
│       └── type
│           ├── sql.rb
├── manifests
    ├── db.pp
    ├── init.pp
    └── web.pp

We can then use the puppet app and puppet job commands to deploy our application.