Question

0. 项目简介

Glance 是 OpenStack Image Service 项目，用于注册、管理和检索虚拟机镜像。 Glance 并不负责实际的镜像存储。它提供了对接简单文件系统，对象存储，块存储等多种存储后端的能力。除了磁盘镜像信息，它还能够存储描述镜像的元数据和状态信息。

1. 先睹为快

不想看下面大段的代码解析，已经跃跃欲试了？

OK，我们开始吧！

创建 puppet_glance.pp 文件并输入:

class  { 'glance::api':
  verbose             => true,
  keystone_tenant     => 'services',
  keystone_user       => 'glance',
  keystone_password   => '12345',
  database_connection => 'mysql://glance:12345@127.0.0.1/glance',
}

class  { 'glance::registry':
  verbose             => true,
  keystone_tenant     => 'services',
  keystone_user       => 'glance',
  keystone_password   => '12345',
  database_connection => 'mysql://glance:12345@127.0.0.1/glance',
}

class  { 'glance::backend::file': }

class  { 'glance::db::mysql':
  password      => '12345',
  allowed_hosts => '%',
}

class  { 'glance::keystone::auth':
  password         => '12345'
  email            => 'glance@example.com',
  public_address   => '127.0.0.1',
  admin_address    => '127.0.0.1',
  internal_address => '172.17.1.3',
  region           => 'example-west-1',
}

rabbitmq_user { 'glance':
  admin    => true,
  password => 'an_even_bigger_secret',
  provider => 'rabbitmqctl',
  require  => Class['::rabbitmq'],
}

rabbitmq_user_permissions { 'glance@/':
  configure_permission => '.*',
  write_permission     => '.*',
  read_permission      => '.*',
  provider             => 'rabbitmqctl',
  require              => Class['::rabbitmq'],
}

在终端执行以下命令:

$ puppet apply -v puppet_glance.pp

2. 核心代码讲解

2.1 class glance

class glance 用于管理 Glance 软件包和 Openstackclient 软件包:

  include ::glance::params

  if ( $glance::params::api_package_name == $glance::params::registry_package_name ) {
    package { $::glance::params::api_package_name :
      ensure => $package_ensure,
      name   => $::glance::params::api_package_name,
      tag    => ['openstack', 'glance-package'],
    }
    include '::openstacklib::openstackclient'
  }

2.2 class glance::api

glance::api 类用于管理以下配置：

1. policy\db\logging\cache

   include ::glance::policy
   include ::glance::api::db
   include ::glance::api::logging
   include ::glance::cache::logging
   

2. /etc/glance/glance-api.conf

   # basic service config
   glance_api_config {
    'DEFAULT/bind_host':               value => $bind_host;
    'DEFAULT/bind_port':               value => $bind_port;
    'DEFAULT/backlog':                 value => $backlog;
    'DEFAULT/show_image_direct_url':   value => $show_image_direct_url;
     ...
    'DEFAULT/image_cache_dir':         value => $image_cache_dir;
    'DEFAULT/auth_region':             value => $auth_region;
    'glance_store/os_region_name':     value => $os_region_name;
   }
   

   3. 管理/etc/glance/glance-cache.conf

在 Glance-api 中，启用 Glance 的缓存功能可以加速镜像的二次下载速度（注：在使用 Ceph 作为 Glance, Cinder, Nova 的后端时，此功能无效)

  glance_cache_config {
    'DEFAULT/image_cache_stall_time': value => $image_cache_stall_time;
    'DEFAULT/image_cache_max_size':   value => $image_cache_max_size;
    'glance_store/os_region_name':    value => $os_region_name;
  }

4. glance-api 服务的管理

  service { 'glance-api':
    ensure     => $service_ensure,
    name       => $::glance::params::api_service_name,
    enable     => $enabled,
    hasstatus  => true,
    hasrestart => true,
    tag        => 'glance-service',
  }

5. 验证 glance-api 服务部署是否成功 通过调用 glance image-list 命令来验证 glance-api 的返回值是否符合预期。

  if $validate {
    $defaults = {
      'glance-api' => {
        'command'  => "glance --os-auth-url ${auth_uri} --os-tenant-name ${keystone_tenant} --os-username ${keystone_user} --os-password ${keystone_password} image-list",
      }
    }
    $validation_options_hash = merge ($defaults, $validation_options)
    create_resources('openstacklib::service_validation', $validation_options_hash, {'subscribe' => 'Service[glance-api]'})
  }

2.3 Class glance::registry

glance::registry 用于安装和配置 glance-registry 服务，其代码结构与 glance::api 类似，在此不做赘述。

Class glance::notify::rabbitmq

在 glance-api 和 glance-registry 中启用 notifications 功能可以在创建镜像，更新镜像源数据等事件发生时发送通知到 rabbitmq 给其他服务使用。

调用 puppet-oslo 来配置 glance-api.conf 和 glance-registry

  oslo::messaging::rabbit { ['glance_api_config', 'glance_registry_config']:
    rabbit_password             => $rabbit_password,
    rabbit_userid               => $rabbit_userid,
    rabbit_host                 => $rabbit_host,
    rabbit_port                 => $rabbit_port,
    rabbit_hosts                => $rabbit_hosts,
    rabbit_virtual_host         => $rabbit_virtual_host,
    rabbit_ha_queues            => $rabbit_ha_queues,
    heartbeat_timeout_threshold => $rabbit_heartbeat_timeout_threshold,
    heartbeat_rate              => $rabbit_heartbeat_rate,
    rabbit_use_ssl              => $rabbit_use_ssl,
    kombu_ssl_ca_certs          => $kombu_ssl_ca_certs,
    kombu_ssl_certfile          => $kombu_ssl_certfile,
    kombu_ssl_keyfile           => $kombu_ssl_keyfile,
    kombu_ssl_version           => $kombu_ssl_version,
    kombu_reconnect_delay       => $kombu_reconnect_delay,
    amqp_durable_queues         => $amqp_durable_queues,
    kombu_compression           => $kombu_compression,
  }


  oslo::messaging::notifications { ['glance_api_config', 'glance_registry_config']:
    driver => $notification_driver,
    topics => $rabbit_notification_topic,
  }

2.4 Class glance::backend::rbd

Glance 支持多种存储后端，比如 cinder,swift,file,ceph,s3，本节将介绍如何使用 glance::backend::rbd 配置 Ceph 作为 Glance 后端存储：

  #修改 glance_store 下的配置项
  glance_api_config {
    'glance_store/rbd_store_ceph_conf':    value => $rbd_store_ceph_conf;
    'glance_store/rbd_store_user':         value => $rbd_store_user;
    'glance_store/rbd_store_pool':         value => $rbd_store_pool;
    'glance_store/rbd_store_chunk_size':   value => $rbd_store_chunk_size;
    'glance_store/rados_connect_timeout':  value => $rados_connect_timeout;
  }

  if !$multi_store {
    glance_api_config { 'glance_store/default_store': value => 'rbd'; }
    if $glare_enabled {
      glance_glare_config { 'glance_store/default_store': value => 'rbd'; }
    }
  }

  #安装 python-ceph 软件包
  package { 'python-ceph':
    ensure => $package_ensure,
    name   => $::glance::params::pyceph_package_name,
  }

3. 动手练习

1. 配置 Glance 使用 Swift 作为存储后端
2. 设置 token 的缓存时间为 5min