Puppet條件語句，class，module的使用

時間 2019-12-19

標籤 puppet 條件語句 class module 使用简体版

原文原文鏈接

1、Puppet條件語句和類node

Puppet2.7系列的版本支持使用3種條件判斷語句，包括：if，case，selector，puppet也支持使用class是用於通用目標的一組資源，所以，它是命名的代碼塊，在某位置建立以後可在puppet全局使用，相似於其餘編程語言中類的功能，puppet的class能夠被繼承，也能夠包含子類。linux

2、Puppet模塊nginx

到目前爲止，資源申報、定義類、聲明類等全部功能都只能再一個manifest文件中實現，但這卻非最有效的基於puppet管理IT基礎架構的方式，實踐中，通常須要把manifest文件分解成易於理解的結構，例如將類文件，配置文件、模塊文件等分類存放，而且經過某種機制在必要時將它們整合起來，這種機制就是「模塊」，它有助於以結構化、層次化的方式使用puppet，而puppet則基於「模塊自動裝載器」完成模塊裝載，模塊實際就是一個按約定的、預約義的結構存放了多個文件或子目錄的目錄，目錄裏的這些文件或子目錄必須遵循其命名規範，puppet會按此種規範在特定位置查找所須要的模塊文件，不過，這些特定的目錄也能夠經過puppet的配置參數modulepath定義。web

首先來演示下if語句的使用，if又包括單分支，雙分支，多分支語句apache

[root@node1 ~]# vi test6.pp
if $operatingsystem =~ /(?i-mx:^(centos|fedora|redhat))/ {
        $webserver = 'httpd'
} elsif operatingsystem  =~ /(?i-mx:^(debian|ubuntu))/ {
        $webserver = 'apache2'
} else {
        $webserver = undef
        notice('Unkown OS')
}
package {"$webserver":
        ensure => installed,
}
[root@node1 ~]# puppet apply test6.pp
notice: /Stage[main]//Package[httpd]/ensure: created
notice: Finished catalog run in 2.91 seconds
[root@node1 ~]# rpm -q httpd
httpd-2.2.15-30.el6.centos.x86_64
# 使用多分支if判斷語句，operatingsystem頂級變量，根據當前系統安裝所要安裝的程序包

case語句，相似if語句，case語句會從多個代碼塊中選擇一個分支執行，這跟其餘編程語言中的case語句功能一致，case語句會接受一個控制表達式和一組case代碼塊，並執行第一個匹配到控制表達式的塊編程

[root@node1 ~]# vi test7.pp
case $operatingsystem {
        'Solaris':              {notice("Welcome to Solaris")}
        'RedHat','CentOS':      {notice("Welcome to RedHat OSFamily")}
        /^(Debian|Ubuntu)$/:    {notice("Welcome to $1 linux")}
        default:                {notice("Welcome,alien *_*")}
}
[root@node1 ~]# puppet apply test7.pp
notice: Scope(Class[main]): Welcome to RedHat OSFamily
notice: Finished catalog run in 0.01 seconds

selector語句，selector只能用於指望出現直接值的地方，這包括變量賦值，資源屬性，函數參數，資源標題，其餘selector的值及表達式，selector不能用於一個已經嵌套於selector的case中，也不能用於一個已經嵌套於case的case語句中
ubuntu

[root@node1 ~]# vi test8.pp
$webserver = $operatingsystem ? {
   /(?i-mx:ubuntu|debian)/        => 'apache2',
   /(?i-mx:centos|fedora|redhat)/ => 'httpd',
}
notify {"$webserver":
        message => "install $webserver",
}
[root@node1 ~]# puppet apply test8.pp
notice: install httpd
notice: /Stage[main]//Notify[httpd]/message: defined 'message' as 'install httpd'
notice: Finished catalog run in 0.02 seconds

class的使用
centos

[root@node1 ~]# vi test9.pp
class nginx {
        package {'nginx':
                ensure => installed,
                before => File['/etc/nginx/nginx.conf'],
                }
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => 0644,
                owner => 'root',
                group => 'root',
                source => '/tmp/nginx.conf',
                notify => Service['nginx'],
             }
        service { 'nginx':
                ensure => running,
                }
}
include nginx
# 使用include來調用class
[root@node1 ~]# puppet apply test9.pp
notice: /Stage[main]/Nginx/Package[nginx]/ensure: created
notice: /Stage[main]/Nginx/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Nginx/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: /Stage[main]/Nginx/Service[nginx]: Triggered 'refresh' from 1 events
notice: Finished catalog run in 2.16 seconds
# 也可使用如下方式調用，這種方式能夠傳遞參數
class nginx {
        package {'nginx':
                ensure => installed,
                before => File['/etc/nginx/nginx.conf'],
                }
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => 0644,
                owner => 'root',
                group => 'root',
                source => '/tmp/nginx.conf',
                notify => Service['nginx'],
             }
        service { 'nginx':
                ensure => running,
                }
}
class {'nginx':}
[root@node1 ~]# puppet apply test9.pp
notice: /Stage[main]/Nginx/Package[nginx]/ensure: created
notice: /Stage[main]/Nginx/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Nginx/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: /Stage[main]/Nginx/Service[nginx]: Triggered 'refresh' from 1 events
notice: Finished catalog run in 2.06 seconds

使用class方法調用類，還能夠傳遞參數實現，根據參數來安裝不一樣的服務，好比想安裝tengine
bash

[root@node1 ~]# vi test9.pp
class webserver ($wbsvr='nginx') {
        package {"$wbsvr":
                ensure => installed,
                before => File['/etc/nginx/nginx.conf'],
                }
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => 0644,
                owner => 'root',
                group => 'root',
                source => '/tmp/nginx.conf',
                notify => Service['nginx'],
             }
        service { 'nginx':
                ensure => running,
                }
}
class {'webserver':
        wbsvr => 'nginx',
}
[root@node1 ~]# puppet apply test9.pp
notice: /Stage[main]/Webserver/Package[nginx]/ensure: created
notice: /Stage[main]/Webserver/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Webserver/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: /Stage[main]/Webserver/Service[nginx]: Triggered 'refresh' from 1 events
notice: Finished catalog run in 2.09 seconds
[root@node1 ~]# vi test9.pp
class webserver ($wbsvr='nginx') {
        package {"$wbsvr":
                ensure => installed,
                before => File['/etc/nginx/nginx.conf'],
                }
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => 0644,
                owner => 'root',
                group => 'root',
                source => '/tmp/nginx.conf',
                notify => Service['nginx'],
             }
        service { 'nginx':
                ensure => running,
                }
}
class {'webserver':
        wbsvr => 'tenginx',
}
[root@node1 ~]# puppet apply test9.pp
err: /Stage[main]/Webserver/Package[tenginx]/ensure: change from absent to present failed: Execution of '/usr/bin/yum -d 0 -e 0 -y install tenginx' returned 1: Error: Nothing to do
notice: /Stage[main]/Webserver/File[/etc/nginx/nginx.conf]: Dependency Package[tenginx] has failures: true
warning: /Stage[main]/Webserver/File[/etc/nginx/nginx.conf]: Skipping because of failed dependencies
notice: /Stage[main]/Webserver/Service[nginx]: Dependency Package[tenginx] has failures: true
warning: /Stage[main]/Webserver/Service[nginx]: Skipping because of failed dependencies
notice: Finished catalog run in 0.41 second

類也能夠被繼承，實現根據不一樣狀況調用不一樣的類架構

[root@node1 ~]# vi test10.pp
class nginx {
        package {'nginx':
                ensure => installed,
        }
}
class nginx::websvr inherits nginx {
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => '0644',
                owner => 'root',
                group => 'root',
                require => Package['nginx'],
                source => '/tmp/nginx.conf',
        }
        service {'nginx':
                ensure => running,
        }
}
class nginx::rproxy inherits nginx {
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => '0644',
                owner => 'root',
                group => 'root',
                require => Package['nginx'],
                source => '/tmp/nginx-proxy.conf',
        }
        service {'nginx':
                ensure => running,
        }
}
include nginx::websvr
[root@node1 ~]# puppet apply test10.pp
notice: /Stage[main]/Nginx/Package[nginx]/ensure: created
notice: /Stage[main]/Nginx::Websvr/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Nginx::Websvr/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: Finished catalog run in 1.81 seconds
# 調用nginx::rproxy類
[root@node1 ~]# vi test10.pp
class nginx {
        package {'nginx':
                ensure => installed,
        }
}
class nginx::websvr inherits nginx {
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => '0644',
                owner => 'root',
                group => 'root',
                require => Package['nginx'],
                source => '/tmp/nginx.conf',
        }
        service {'nginx':
                ensure => running,
        }
}
class nginx::rproxy inherits nginx {
        file {'/etc/nginx/nginx.conf':
                ensure => file,
                mode => '0644',
                owner => 'root',
                group => 'root',
                require => Package['nginx'],
                source => '/tmp/nginx-proxy.conf',
        }
        service {'nginx':
                ensure => running,
        }
}
include nginx::rproxy
[root@node1 ~]# puppet apply test10.pp
notice: Finished catalog run in 0.15 seconds

puppet模塊的建立和使用

# 安裝puppet-server
[root@node1 ~]# rpm -ivh puppet-server-2.7.23-1.el6.noarch.rpm

# 建立模塊目錄結構
[root@node1 ~]# mkdir -pv /etc/puppet/modules/nginx/{manifests,files,lib,templates,tests,spec}
mkdir: created directory `/etc/puppet/modules/nginx'
mkdir: created directory `/etc/puppet/modules/nginx/manifests'
mkdir: created directory `/etc/puppet/modules/nginx/files'
mkdir: created directory `/etc/puppet/modules/nginx/lib'
mkdir: created directory `/etc/puppet/modules/nginx/templates'
mkdir: created directory `/etc/puppet/modules/nginx/tests'
mkdir: created directory `/etc/puppet/modules/nginx/spec'
[root@node1 ~]# puppet module list
/etc/puppet/modules
└── nginx (???)
/usr/share/puppet/modules (no modules installed)

MODULE NAME：模塊名稱，只能以小寫字母開頭，也能夠包含小寫字母、數字和下劃線，但不能使用「main」或者「settings」做爲模塊名；

manifests目錄：包含當前模塊的全部manifest文件；每一個mainfest文件必須包含一個類或一個定義的類，此文件訪問路徑格式爲"ModuleName::[SubDircetoryName::]ManifestFileName"，注意manifest文件不須要其後綴.pp；

init.pp：只能包含一個單獨的類定義，且類的名稱必須與模塊名稱相同；

files目錄：包含了一組靜態文件，這些文件可被節點下載使用，每一個文件的訪問路徑遵循

puppet:///modules/MODULE_NAME/filename路徑格式；

lib目錄：插件目錄，經常使用於自定義fact及自定義資源類型等；

templates目錄：存儲了manifest用到的模板文件，其訪問路徑遵循template('ModulName/TemplateName')格式；

tests目錄：當前模塊的使用幫助或使用範例文件，相似如何聲明當前模塊中的類定義的類型等；

spec目錄：相似於tests目錄的功能，只不過，其是爲lib目錄中定義的各插件提供使用的範例的；

在nginx模塊中定義init.pp

[root@node1 ~]# vi /etc/puppet/modules/nginx/manifests/init.pp
class nginx {
        package {'nginx':
              ensure => installed,
        }
}

定義nginx_web.pp文件

[root@node1 ~]# vi /etc/puppet/modules/nginx/manifests/nginx_web.pp
class nginx::nginx_web inherits nginx {
        file {'/etc/nginx/nginx.conf':
            ensure => file,
            source => 'puppet:///modules/nginx/nginx-web.conf',
            mode => '0644',
            owner => 'root',
            group => 'root',
            notify => Service['nginx'],
            require => Package['nginx'],
        }
        service {'nginx':
            ensure => running,
}
}
# 準備source文件
[root@node1 ~]# cp /tmp/nginx.conf /etc/puppet/modules/nginx/files/nginx-web.conf

定義nginx_proxy.pp文件

[root@node1 ~]# vi /etc/puppet/modules/nginx/manifests/nginx_proxy.pp
class nginx::nginx_proxy inherits nginx {
        file {'/etc/nginx/nginx.conf':
            ensure => file,
            source => 'puppet:///modules/nginx/nginx-proxy.conf',
            mode => '0644',
            owner => 'root',
            group => 'root',
            notify => Service['nginx'],
            require => Package['nginx'],
        }
        service {'nginx':
            ensure => running,
}
}
# 準備source文件
[root@node1 ~]# cp /tmp/nginx.conf /etc/puppet/modules/nginx/files/nginx-proxy.conf

建立site.pp文件調用前面定義的class

[root@node1 ~]# vi /etc/puppet/manifests/site.pp
node 'node1.luojianlong' {
        include nginx::nginx_web
}

執行操做

[root@node1 ~]# puppet apply /etc/puppet/manifests/site.pp
notice: /Stage[main]/Nginx/Package[nginx]/ensure: created
notice: /Stage[main]/Nginx::Nginx_web/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Nginx::Nginx_web/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: /Stage[main]/Nginx::Nginx_web/Service[nginx]: Triggered 'refresh' from 1 events
notice: Finished catalog run in 2.05 seconds

這樣就是使用nginx-web.conf配置文件啓動的nginx

也可使用nginx-proxy.conf，啓動

[root@node1 ~]# vi /etc/puppet/manifests/site.pp
node 'node1.luojianlong' {
        include nginx::nginx_proxy
}
[root@node1 ~]# yum -y remove nginx
[root@node1 ~]# puppet apply /etc/puppet/manifests/site.pp
notice: /Stage[main]/Nginx/Package[nginx]/ensure: created
notice: /Stage[main]/Nginx::Nginx_proxy/File[/etc/nginx/nginx.conf]/content: content changed '{md5}d9dfc198c249bb4ac341198a752b9458' to '{md5}95f45f10386878664af2b7ccd1536ea4'
notice: /Stage[main]/Nginx::Nginx_proxy/Service[nginx]/ensure: ensure changed 'stopped' to 'running'
notice: /Stage[main]/Nginx::Nginx_proxy/Service[nginx]: Triggered 'refresh' from 1 events
notice: Finished catalog run in 2.11 seconds
# 執行成功

到此，Puppet條件語句，class，module的使用就介紹這麼多了。