Puppet – 资源抽象层

在 Puppet 中，资源抽象层 (RAL) 可以被视为整个基础设施和 Puppet 设置工作的核心概念化模型。在 RAL 中，每个字母都有自己的重要意义，定义如下。

资源 [R]

一个资源可以被认为是用于在 Puppet 中对任何配置进行建模的所有资源。它们基本上是内置资源，默认情况下存在于 Puppet 中。它们可以被视为属于预定义资源类型的一组资源。它们类似于任何其他编程语言中的 OOP 概念，其中对象是类的实例。在 Puppet 中，它的资源是一个资源类型的实例。

抽象 [A]

抽象可以被视为一个关键特性，其中资源是独立于目标操作系统定义的。换句话说，在编写任何清单文件时，用户无需担心目标机器或存在于该特定机器上的操作系统。抽象地说，资源提供了有关 Puppet 代理上需要存在的内容的足够信息。

Puppet 将处理幕后发生的所有功能或魔法。无论资源和操作系统如何，Puppet 都会负责在目标机器上实现配置，用户无需担心 Puppet 在幕后做了什么。

在抽象中，Puppet 将资源与其实现分离。此特定于平台的配置存在于提供商处。我们可以使用多个子命令及其提供程序。

层 [L]

可以根据资源集合定义整个机器设置和配置，并且可以通过 Puppet 的 CLI 界面进行查看和管理。

用户资源类型示例

[root@puppetmaster ~]# puppet describe user --providers 
user 
==== 
Manage users.
This type is mostly built to manage systemusers, 
so it is lacking some features useful for managing normalusers. 
This resource type uses the prescribed native tools for 
creating groups and generally uses POSIX APIs for retrieving informationabout them.
It does not directly modify '/etc/passwd' or anything. 

- **comment** 
   A description of the user.  Generally the user's full name.  

- **ensure** 
   The basic state that the object should be in. 
   Valid values are 'present', 'absent', 'role'.  

- **expiry** 
   The expiry date for this user. 
   Must be provided in a zero-padded YYYY-MM-DD format --- e.g. 2010-02-19. 
   If you want to make sure the user account does never expire, 
   you can pass the special value 'absent'. 
   Valid values are 'absent'. 
   Values can match '/^\d{4}-\d{2}-\d{2}$/'. 
   Requires features manages_expiry.  

- **forcelocal** 
   Forces the management of local accounts when accounts are also 
   being managed by some other NSS 
   Valid values are 'true', 'false', 'yes', 'no'. 
   Requires features libuser.  

- **gid** 
   The user's primary group.  Can be specified numerically or by name. 
   This attribute is not supported on Windows systems; use the ‘groups’ 
   attribute instead. (On Windows, designating a primary group is only 
   meaningful for domain accounts, which Puppet does not currently manage.)  

- **groups** 
   The groups to which the user belongs. The primary group should 
   not be listed, and groups should be identified by name rather than by 
   GID. Multiple groups should be specified as an array.  

- **home** 
   The home directory of the user.  The directory must be created 
   separately and is not currently checked for existence.  

- **ia_load_module**
   The name of the I&A module to use to manage this user. 
   Requires features manages_aix_lam.  

- **iterations** 
   This is the number of iterations of a chained computation of the 
   password hash (http://en.wikipedia.org/wiki/PBKDF2).  
   This parameter is used in OS X. 
   This field is required for managing passwords on OS X >= 10.8.  

- **key_membership** 
   Whether specified key/value pairs should be considered the 
   **complete list** ('inclusive') or the **minimum list** ('minimum') of 
   the user's attributes. Defaults to 'minimum'. 
   Valid values are 'inclusive', 'minimum'.  

- **keys** 
   Specify user attributes in an array of key = value pairs. 
   Requires features manages_solaris_rbac.  

- **managehome** 
   Whether to manage the home directory when managing the user. 
   This will create the home directory when 'ensure => present', and 
   delete the home directory when ‘ensure => absent’. Defaults to ‘false’. 
   Valid values are ‘true’, ‘false’, ‘yes’, ‘no’.  

- **membership** 
   Whether specified groups should be considered the **complete list** 
   (‘inclusive’) or the **minimum list** (‘minimum’) of groups to which 
   the user belongs. Defaults to ‘minimum’. 
   Valid values are ‘inclusive’, ‘minimum’. 

- **name** 
   The user name. While naming limitations vary by operating system, 
   it is advisable to restrict names to the lowest common denominator.  

- **password** 
   The user's password, in whatever encrypted format the local system requires. 
   * Most modern Unix-like systems use salted SHA1 password hashes. You can use 
      Puppet's built-in ‘sha1’ function to generate a hash from a password. 
   * Mac OS X 10.5 and 10.6 also use salted SHA1 hashes. 
   * Mac OS X 10.7 (Lion) uses salted SHA512 hashes. 
   The Puppet Labs [stdlib][] module contains a ‘str2saltedsha512’ 
   function which can generate password hashes for Lion. 
   * Mac OS X 10.8 and higher use salted SHA512 PBKDF2 hashes. 
   When managing passwords on these systems the salt and iterations properties 
   need to be specified as well as the password. 
   [stdlib]: https://github.com/puppetlabs/puppetlabs-stdlib/ 
   Be sure to enclose any value that includes a dollar sign ($) in single 
   quotes (') to avoid accidental variable interpolation. 
   Requires features manages_passwords.  

- **password_max_age** 
   The maximum number of days a password may be used before it must be changed. 
Requires features manages_password_age.  

- **password_min_age** 
   The minimum number of days a password must be used before it may be changed. 
Requires features manages_password_age.  

- **profile_membership** 
   Whether specified roles should be treated as the **complete list** 
   (‘inclusive’) or the **minimum list** (‘minimum’) of roles 
   of which the user is a member. Defaults to ‘minimum’. 
   Valid values are ‘inclusive’, ‘minimum’. 

- **profiles** 
   The profiles the user has.  Multiple profiles should be 
   specified as an array. 
Requires features manages_solaris_rbac.  

- **project** 
   The name of the project associated with a user. 
   Requires features manages_solaris_rbac.  

- **purge_ssh_keys** 
   Purge ssh keys authorized for the user 
   if they are not managed via ssh_authorized_keys. 
   When true, looks for keys in .ssh/authorized_keys in the user's home directory. 
   Possible values are true, false, or an array of 
   paths to file to search for authorized keys. 
   If a path starts with ~ or %h, this token is replaced with the user's home directory. 
   Valid values are ‘true’, ‘false’.  

- **role_membership** 
   Whether specified roles should be considered the **complete list** 
   (‘inclusive’) or the **minimum list** (‘minimum’) of roles the user has. 
   Defaults to ‘minimum’. 
Valid values are ‘inclusive’, ‘minimum’.  

- **roles** 
   The roles the user has.  Multiple roles should be 
   specified as an array. 
Requires features manages_solaris_rbac.  

- **salt** 
   This is the 32 byte salt used to generate the PBKDF2 password used in 
   OS X. This field is required for managing passwords on OS X >= 10.8. 
   Requires features manages_password_salt. 

- **shell** 
   The user's login shell.  The shell must exist and be 
   executable. 
   This attribute cannot be managed on Windows systems. 
   Requires features manages_shell. 

- **system** 
   Whether the user is a system user, according to the OS's criteria; 
   on most platforms, a UID less than or equal to 500 indicates a system 
   user. Defaults to ‘false’. 
   Valid values are ‘true’, ‘false’, ‘yes’, ‘no’.  

- **uid** 
   The user ID; must be specified numerically. If no user ID is 
   specified when creating a new user, then one will be chosen 
   automatically. This will likely result in the same user having 
   different UIDs on different systems, which is not recommended. 
   This is especially noteworthy when managing the same user on both Darwin and 
   other platforms, since Puppet does UID generation on Darwin, but 
   the underlying tools do so on other platforms. 
   On Windows, this property is read-only and will return the user's 
   security identifier (SID).  

Providers 
--------- 

- **aix** 
   User management for AIX. 
   * Required binaries: '/bin/chpasswd', '/usr/bin/chuser', 
   '/usr/bin/mkuser', '/usr/sbin/lsgroup', '/usr/sbin/lsuser', 
   '/usr/sbin/rmuser'. 
   * Default for ‘operatingsystem’ == ‘aix’. 
   * Supported features: ‘manages_aix_lam’, ‘manages_expiry’, 
   ‘manages_homedir’, ‘manages_password_age’, ‘manages_passwords’, 
   ‘manages_shell’. 

- **directoryservice** 
   User management on OS X. 
   * Required binaries: ‘/usr/bin/dscacheutil’, ‘/usr/bin/dscl’, 
   ‘/usr/bin/dsimport’, ‘/usr/bin/plutil’, ‘/usr/bin/uuidgen’. 
   * Default for ‘operatingsystem’ == ‘darwin’. 
   * Supported features: ‘manages_password_salt’, ‘manages_passwords’, 
   ‘manages_shell’.

- **hpuxuseradd** 
   User management for HP-UX. This provider uses the undocumented ‘-F’ 
   switch to HP-UX's special ‘usermod’ binary to work around the fact that 
   its standard ‘usermod’ cannot make changes while the user is logged in. 
   * Required binaries: ‘/usr/sam/lbin/useradd.sam’, 
   ‘/usr/sam/lbin/userdel.sam’, ‘/usr/sam/lbin/usermod.sam’. 
   * Default for ‘operatingsystem’ == ‘hp-ux’. 
   * Supported features: ‘allows_duplicates’, ‘manages_homedir’, 
   ‘manages_passwords’.  

- **ldap** 
   User management via LDAP. 
   This provider requires that you have valid values for all of the 
   LDAP-related settings in ‘puppet.conf’, including ‘ldapbase’.
   You will almost definitely need settings for ‘ldapuser’ and ‘ldappassword’ in order 
   for your clients to write to LDAP. 
* Supported features: ‘manages_passwords’, ‘manages_shell’.  

- **pw** 
   User management via ‘pw’ on FreeBSD and DragonFly BSD. 
   * Required binaries: ‘pw’. 
   * Default for ‘operatingsystem’ == ‘freebsd, dragonfly’. 
   * Supported features: ‘allows_duplicates’, ‘manages_expiry’, 
   ‘manages_homedir’, ‘manages_passwords’, ‘manages_shell’. 

- **user_role_add** 
   User and role management on Solaris, via ‘useradd’ and ‘roleadd’. 
   * Required binaries: ‘passwd’, ‘roleadd’, ‘roledel’, ‘rolemod’, 
   ‘useradd’, ‘userdel’, ‘usermod’. 
   * Default for ‘osfamily’ == ‘solaris’. 
   * Supported features: ‘allows_duplicates’, ‘manages_homedir’, 
   ‘manages_password_age’, ‘manages_passwords’, ‘manages_solaris_rbac’.  

- **useradd** 
   User management via ‘useradd’ and its ilk.  Note that you will need to 
   install Ruby's shadow password library (often known as ‘ruby-libshadow’) 
   if you wish to manage user passwords. 
   * Required binaries: ‘chage’, ‘luseradd’, ‘useradd’, ‘userdel’, ‘usermod’. 
   * Supported features: ‘allows_duplicates’, ‘libuser’, ‘manages_expiry’, 
   ‘manages_homedir’, ‘manages_password_age’, ‘manages_passwords’, 
   ‘manages_shell’, ‘system_users’.  

- **windows_adsi** 
   Local user management for Windows. 
   * Default for 'operatingsystem' == 'windows'. 
   * Supported features: 'manages_homedir', 'manages_passwords'. 

测试资源

在Puppet中，直接测试一个资源，就是先申请一个自己想使用的资源来配置一个目标节点，这样机器的状态就会随之改变。

为了测试，我们将在本地应用资源。因为我们有一个上面预定义的资源user = vipin。应用资源的一种方法是通过 CLI。这可以通过将完整资源重新写入单个命令，然后将其传递给资源子命令来完成。

puppet resource user vipin ensure = present uid = '505' 
shell = '/bin/bash' home = '/home/vipin'

测试应用的资源。

[root@puppetmaster ~]# cat /etc/passwd | grep "vipin" 
vipin:x:505:501::/home/vipin:/bin/bash 

上面的输出显示资源已应用于系统，我们创建了一个名为 Vipin 的新用户。建议您自行测试，因为上述所有代码都经过测试并且是工作代码。