目前puppet2.7以上版本都支持if...elif ...else...、selecter和case語句.它們的條件判斷分為兩類:一類為條件執行(if...elif ...else...、selecter)通過邏輯判斷來選擇要執行的特定代碼或加載代碼;另一類(case)是循環執行類,依照代碼規則來執行代碼或加載代碼.

if條件判斷語句:

示例一:

if判斷系統發行版本安裝apache軟件包:

[[email protected] ~]# cat apache.pp 
if $operatingsystem == ‘CentOS‘ {
    $packages = ‘httpd‘
} elsif $operatingsystem == ‘Redhat‘ {
    $packages = ‘httpd‘
} else {
    $packages = ‘apache2‘
}
    package {"$packages":
    ensure=> "present",
}

本地應用puppet代碼:

[[email protected] ~]# puppet apply apache.pp 
Notice: Compiled catalog for sh-web1.localdomain in environment production in 0.04 seconds
Notice: /Stage[main]/Main/Package[httpd]/ensure: created
Notice: Finished catalog run in 1.78 seconds

註意:"=="是等於的意思，完完全全匹配到對應的.

示例二:

if匹配hostname主機載入相應的puppet模塊.(if在node.pp文件中匹配主機很少用,幾乎都是用case.)

node base {
    include admin
}
node /sh-(proxy|web)\d+/  inherits base {
    if $hostname =~ /sh-proxy\d+/ {
        include apache
    } elsif $hostname =~ /sh-web\d+/ {
        include php
    } else {
        include nginx::nginxconf
    }
}

agent端更新puppet代碼.

[[email protected] ~]# puppet agent -t
Info: Retrieving pluginfacts
Info: Retrieving plugin
Info: Loading facts
Info: Caching catalog for sh-proxy2.localdomain
Info: Applying configuration version ‘1506450177‘
Notice: /Stage[main]/Admin/Exec[selinux]/returns: executed successfully
Notice: /Stage[main]/Install/Package[httpd]/ensure: created
Notice: /Stage[main]/Service/Service[httpd]/ensure: ensure changed ‘stopped‘ to ‘running‘
Info: /Service[httpd]: Unscheduling refresh on Service[httpd]
Notice: Finished catalog run in 20.24 seconds

agent端更新puppet代碼.

[[email protected] ~]# puppet agent -t
Notice: Ignoring --listen on onetime run
Info: Retrieving pluginfacts
Info: Retrieving plugin
Info: Loading facts
Info: Caching catalog for sh-web1.localdomain
Info: Applying configuration version ‘1506450177‘
Notice: /Stage[main]/Admin/Exec[selinux]/returns: executed successfully
Notice: /Stage[main]/Php/Package[php]/ensure: created
Notice: /Stage[main]/Php/Package[php-devel]/ensure: created
Notice: Finished catalog run in 4.01 seconds

註意:"=~"是匹配的意思，只要匹配到就行.

case語句應用:

示例:(之前文章一直都在用的匹配方法case)

node base {
include admin
}
node /sh-(proxy|web)\d+/  inherits base {
  case $::hostname {
    /sh-proxy\d+/: {
         include apache
      }
     "sh-web1": {
            include nginx::nginxconf
            include php
         } 
    }
}

agent端更新就不演示了,上面的case語句博客開始就是這樣寫的.

本文出自 “青衫解衣” 博客，請務必保留此出處http://215687833.blog.51cto.com/6724358/1969088

Puppet 條件判斷語句(十六)