前文我們瞭解了puppet的file、exec、cron、notify這四種核心資源類型的使用以及資源見定義通知/訂閱關係，回顧請參考https://www.cnblogs.com/qiuhom-1874/p/14073437.html；今天我們來了解下puppet中的變量、正則表達式、流程控制、類和模板的相關話題；
puppet中的變量
在puppet中變量的定義和使用都是要加“$”，比如定義變量$webserver=nginx；則表示把nginx這個字符串複製給$webserver這個變量；引用變量直接使用$webserver即可；在puppet中賦值操作符爲“=”,表示把等號右邊邊的值賦給左邊的變量，任何正常數據類型（非正則）的值都可以賦予puppet中的變量，比如字符串、數值、布爾值、數組、hash以及特殊的undef值（即變量未賦值）；
puppet中的數據類型
字符型：非結構化的文本字符串，可以使用引號，也可以不使用引號；單引號表示強引用，雙引號表示弱引用；所謂強引用表示變量不會替換，弱引用表示能夠進行變量替換；字符型值是支持用轉義符；
數字型：可爲整數或浮點數，不過，puppet只有在數值上下文才把數值當作數值型對待，其他情況一律以字符型處理；比如進行加減乘除等運算時，它會把數值型值當作數值進行計算；
數組：數組值爲中括號“[]”中的以逗號分隔的項目列表，最後一個項目後面可以沒有逗號；數組中的元素可以爲任意可用數據類型，包括hash或其他數組，數組中的元素爲數組，我們把這樣的數組叫多維數組；數組的索引爲從0開始的整數，也可以使用負數索引；
布爾型：true和false,不能加任何引號；if語句的測試條件和比較表達式都會返回布爾型值，另外，其他數據類型也可以自動轉換爲布爾型值，如字符串，空串爲false,非空則true;數值型就是0爲false,非0爲true等等；
undef：從未被聲明的變量的值類型即爲undef；也可手動爲某變量賦予undef值，即直接使用不加引號的undef字符串；有點類似shell中的unset；
hash：即爲外鍵值數據類型，鍵和值之間使用“=>”分隔，鍵值對定義在“{}”中，彼此間以逗號分隔；其鍵爲字符型數據，而值可以爲puppet中支持的任意數據類型；訪問hash類型的數據元素要使用“鍵”當作索引進行訪問；
puppet中變量作用域
提示：所謂變量作用域表示變量的使用生效的範圍，在puppet中作用域可用於限定變量及資源默認屬性的作用範圍；但不能用於限定資源名稱及資源引用的生效範圍；任何給定的scope都可以訪問它自己的內容，以及接收來自於其父scope、節點scope以及top scope的內容；簡單講就是作用域小的可以引用作用域大的變量，也可以更改作用域大的變量的值；但是作用域大的不能操作作用域小的變量；如上圖所示，top scope僅能訪問直接的變量和屬性默認值；node scope能訪問自己的及top scope的變量和屬性默認值；example::parent,example::other和example::four能訪問自己的以及節點scope和top scope的變量和默認值；如果要訪問非當前scope中的變量，則需要通過完全限制名稱進行；如$vhostdir=$apache::params::vhostdir；這裏需要注意一點，如果top scope的名稱爲空，如要引用其變量可以使用類似$::sofamily的方式進行引用；
puppet中的內建變量
在puppet中變量來源可以從facter，agent，master，解釋器以及用戶自定義的變量；其中facter是一個工具，它可以收集系統信息，規範化之後存放在一系列變量中，並傳遞給puppet;facter的各變量是top scope的變量，這意味着，可以在各個manifest中直接通過${fact name}訪問所需的fact變量；查看系統fact變量有哪些，可以使用facter -p輸出fact變量；agent端的變量常用的有$environment這表示agent端的環境變量，$clientcert表示agent端的證書；$clientversion表示agent puppet的版本信息；master 端常用變量有$servername，該變量表示服務端名稱；$serverip服務端ip，$serverversion服務端puppet的版本信息；解釋器中的變量$module_name表示正在執行的模塊名稱；這裏需要注意agent和master的內建變量只有在master/agent這種模型中才有效，單機模型無效；
puppet中常用的操作符
| 操作符 | 描述 | 操作符 | 描述 | 操作符 | 描述 |
| == | 等於 | =~ | 正則模式匹配 | + | 加 |
| ！= | 不等於 | !~ | 正則模式不匹配 | - | 減 |
| < | 小於 | in | 成員關係判定 | * | 乘 |
| > | 大於 | and | 與 | / | 除 |
| <= | 小於等於 | or | 或 | << | 左移位 |
| >= | 大於等於 | ! | 非 | >> | 右移位 |
puppet中的正則表達式
正則表達式在puppet中屬於非標準的數據類型，不能賦值給變量，僅能用於有限的幾個接受正則表達式的地方使用，即接受使用“=～”或“！～”匹配操作符的位置，通常包含case語句中的selector,以及節點名稱匹配的位置；它不能傳遞給函數或用於資源屬性定義；
puppet中正則表達式的兩個特殊使用方式
(?<ENABLED OPTION>:<PATTERN>)和(?-<DISABLED OPTION>:<PATTERN>)，其中OPTIONS有i，m，x，其中i表示忽略字符大小寫；m表示把“.”點號當作換行符；x表示忽略<PATTERN>中的空白字符；比如(?imx:PATTENR)就表示忽略字符大小寫，把PATTERN中的點號當作換行符，並且忽略其中的空白字符；(?i-mx:PATTERN)表示忽略字符大小寫，不把pattern中的點號當換行符，也不忽略pattern中的空白字符；
puppet中的流程控制
所謂流程控制就是在puppet代碼中加入了條件控制語句，如if語句，case語句，selector語句，只有滿足了條件纔會執行對應的代碼；if語句語法如下
單分支
if CONDITION {
...
}
雙分支
if CONDITION {
...
} else {
...
}
多分支
if CONDITION {
...
} elsif {
...
} else{
...
}
提示：條件可以是變量，比較表達式或有返回值的函數；
示例：通過判斷不同操作系統來安裝apache
[root@node12 ~]# cat if.pp
if $operatingsystem == "CentOS" {
$webserver = "httpd"
}elsif $operatingsystem == "Ubuntu" {
$webserver = "apache2"
}else{
$webserver = "apahce"
}
package{"$webserver":
ensure => installed,
}
[root@node12 ~]#
提示：以上資源清單表示，通過判斷$operatingsystem這個變量的值來賦值$webserver的值；如果對應$operatingsystem的值爲CentOS，則$webserver的值就爲httpd,如果是Ubuntu $webserver的值就爲apache2，如果前兩個條件都不滿足，則$webserver的值爲apache；然後通過$webserver這個變量的值來安裝包；
應用資源清單
[root@node12 ~]# puppet apply -v --noop if.pp Notice: Compiled catalog for node12.test.org in environment production in 0.65 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606994860' Notice: /Stage[main]/Main/Package[httpd]/ensure: current_value absent, should be present (noop) Notice: Class[Main]: Would have triggered 'refresh' from 1 events Notice: Stage[main]: Would have triggered 'refresh' from 1 events Notice: Finished catalog run in 1.24 seconds [root@node12 ~]# puppet apply -v if.pp Notice: Compiled catalog for node12.test.org in environment production in 0.18 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606994891' Notice: /Stage[main]/Main/Package[httpd]/ensure: created Notice: Finished catalog run in 7.99 seconds [root@node12 ~]#
提示：從上述信息中可以看到，當前安裝的包上httpd；原因是本機是一個centos系統；$operatingsystem這個變量是一個fact變量，主要保存操作系統名稱；
示例：if語句中使用正則表達式
[root@node12 ~]# cat if.pp
if $operatingsystem =~/(?i-mx:(centos|redhat))/{
$webserver = "httpd"
}elsif $operatingsystem =~ /(?i-mx:(ubuntu|debian))/{
$webserver = "apache2"
}else{
$webserver = "apahce"
}
package{"$webserver":
ensure => installed,
}
[root@node12 ~]#
提示：使用正則表達式需要將正則表達式寫在“//”之間；
卸載httpd,應用資源清單
[root@node12 ~]# rpm -e httpd [root@node12 ~]# puppet apply -v if.pp Notice: Compiled catalog for node12.test.org in environment production in 0.18 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606995583' Notice: /Stage[main]/Main/Package[httpd]/ensure: created Notice: Finished catalog run in 1.86 seconds [root@node12 ~]#
提示：可以看到應用清單並沒有報錯，提示httpd已經創建；
puppet中的case語句
語法
case CONTROL_EXPRESSION {
case1: { ... }
case2: { ... }
case3: { ... }
...
default: { ... }
}
提示：case語句和if語句的作用是類似的，case語句會從多個代碼塊中選擇一個分支執行，只要其中任意一個case的值滿足對應的控制表達式，就執行對應case後面的代碼塊，然後退出；如果所有case都不滿足，則執行default對應的代碼塊；這裏的控制表達式可以是變量，可以是比較表達式，也可以是有返回值的函數；case可以是字符串，正則表達式，變量，有返回值的函數和default；
示例
[root@node12 ~]# cat case.pp
case $osfamily {
"RedHat":{ $webserver="httpd" }
/(?i-mx:debian)/:{ $webserver="apache2" }
default:{ $webserver="apache" }
}
package{"$webserver":
ensure => installed,
}
[root@node12 ~]#
卸載httpd，執行資源清單，看看httpd是否會被安裝？
[root@node12 ~]# rpm -e httpd [root@node12 ~]# puppet apply -v case.pp Notice: Compiled catalog for node12.test.org in environment production in 0.18 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606996150' Notice: /Stage[main]/Main/Package[httpd]/ensure: created Notice: Finished catalog run in 1.82 seconds [root@node12 ~]# rpm -q httpd httpd-2.4.6-97.el7.centos.x86_64 [root@node12 ~]#
提示：可以看到httpd可以正常的安裝；
selector語句
語法
CONTROL_VARIABLE ? {
case1 => value1,
case2 => value2,
...
default => valueN,
}
提示：整個selector語句會被當作一個單獨的值，puppet會將控制變量按列出的次序依次與每個case進行比較，並在遇到一個匹配的case後，將其值作爲整個語句的值進行返回，並忽略後面的其他case；控制變量與各case比較的方式和case語句相同，但如果沒有任何一個case與控制變量匹配，puppet在編譯時將報錯，因此，我們在使用selector必須提供一個default case;控制變量只能是一個變量或一個有返回值的函數，不能使用表達式；各個case的值可以是字符串，變量，有返回值的函數，正則表達式或default；
示例
[root@node12 ~]# cat selector.pp
$pkgname = $operatingsystem ? {
/(?i-mx:(ubuntu|debian))/ => 'apache2',
/(?i-mx:(redhat|fedora|centos))/ => 'httpd',
default => 'apache',
}
package{"$pkgname":
ensure => installed,
}
[root@node12 ~]#
卸載httpd,應用資源清單
[root@node12 ~]# rpm -e httpd [root@node12 ~]# puppet apply -v --noop selector.pp Notice: Compiled catalog for node12.test.org in environment production in 0.18 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606997882' Notice: /Stage[main]/Main/Package[httpd]/ensure: current_value absent, should be present (noop) Notice: Class[Main]: Would have triggered 'refresh' from 1 events Notice: Stage[main]: Would have triggered 'refresh' from 1 events Notice: Finished catalog run in 0.08 seconds [root@node12 ~]# puppet apply -v selector.pp Notice: Compiled catalog for node12.test.org in environment production in 0.18 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1606997889' Notice: /Stage[main]/Main/Package[httpd]/ensure: created Notice: Finished catalog run in 1.96 seconds [root@node12 ~]# rpm -q httpd httpd-2.4.6-97.el7.centos.x86_64 [root@node12 ~]#
提示：可以看到httpd通過使用selector的方式定義的資源清單一樣可以正常安裝；
puppet中的類
類是用於同於目標的一組資源，因此，它是命名的代碼塊，在某一個位置創建之後可在puppet全局使用；puppet中的類和其他編程語言中的類的功能很類似，puppet中的類可被繼承，也可以有子類；
類的定義語法
class class_name($var1=value1,$var2=value2){
... puppet code ...
}
提示：class是關鍵字，class_name是類名，類名只能以小寫字母開頭，可以包含小寫字母，數字，下劃線；小括號裏是定義類的形參，每個形參可以有默認值，也可以沒有，多個形參用逗號隔開；大括號裏寫puppet的代碼；
示例：定義一個apache的類
[root@node12 ~]# cat apache.pp
class apache {
package{"httpd":
ensure => installed,
}
service{"httpd":
ensure => running,
}
}
[root@node12 ~]#
提示：以上清單中定義了一個apache的類，主要完成了安裝包和啓動服務；這裏需要注意一點，類定義好以後，如果我們不聲明類，則它不會執行，有點類似函數一樣，要向讓類執行，我們需要聲明類；
在puppet中類的聲明常用的方式有兩種，第一種是使用include關鍵字+類名；第二種是類似定義資源一樣來聲明類，其中資源類型爲class，title必須爲類名，這種方式通常用於有參數的類的聲明；
示例：使用include關鍵字+類名聲明類
[root@node12 ~]# cat apache.pp
class apache {
package{"httpd":
ensure => installed,
}
service{"httpd":
ensure => running,
}
}
include apache
[root@node12 ~]#
執行清單
[root@node12 ~]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:26379 *:* LISTEN 0 128 *:22 *:* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 128 *:27017 *:* LISTEN 0 128 :::22 :::* LISTEN 0 100 ::1:25 :::* [root@node12 ~]# puppet apply -v --noop apache.pp Notice: Compiled catalog for node12.test.org in environment production in 0.26 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1607005266' Notice: /Stage[main]/Apache/Service[httpd]/ensure: current_value stopped, should be running (noop) Info: /Stage[main]/Apache/Service[httpd]: Unscheduling refresh on Service[httpd] Notice: Class[Apache]: Would have triggered 'refresh' from 1 events Notice: Stage[main]: Would have triggered 'refresh' from 1 events Notice: Finished catalog run in 0.13 seconds [root@node12 ~]# puppet apply -v apache.pp Notice: Compiled catalog for node12.test.org in environment production in 0.27 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1607005272' Notice: /Stage[main]/Apache/Service[httpd]/ensure: ensure changed 'stopped' to 'running' Info: /Stage[main]/Apache/Service[httpd]: Unscheduling refresh on Service[httpd] Notice: Finished catalog run in 0.22 seconds [root@node12 ~]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:26379 *:* LISTEN 0 128 *:22 *:* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 128 *:27017 *:* LISTEN 0 128 :::80 :::* LISTEN 0 128 :::22 :::* LISTEN 0 100 ::1:25 :::* [root@node12 ~]#
提示：可以看到httpd服務已經啓動；
示例：定義帶參類
[root@node12 ~]# cat class1.pp
class dbserver ($pkg='mariadb-server',$svr='mariadb'){
package{"$pkg":
ensure => latest,
}
service{"$svr":
ensure => running,
enable => true,
}
}
if $operatingsystem == "CentOS" or $operatingsystem == "RedHat"{
case $operatingsystemmajrelease {
'7': { $pkgname='mariadb-server' $svrname='mariadb' }
default: { $pkgname='mysql-server' $svrname='mysqld' }
}
}
class{"dbserver":
pkg => $pkgname,
svr => $svrname,
}
[root@node12 ~]#
提示：以上清單主要完成對於不同版本的centos，安裝和啓動不同的服務；在centos7上安裝mariadb-server，啓動mariadb服務；其他版本的centos安裝mysql-server,啓動mysqld服務；這裏需要注意一點，聲明類中的行參不能帶$，我們可以理解爲行參就是類的一個屬性；
執行清單
[root@node12 ~]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:26379 *:* LISTEN 0 128 *:22 *:* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 128 *:27017 *:* LISTEN 0 128 :::80 :::* LISTEN 0 128 :::22 :::* LISTEN 0 100 ::1:25 :::* [root@node12 ~]# puppet apply -v --noop class1.pp Notice: Compiled catalog for node12.test.org in environment production in 0.27 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1607007562' Notice: /Stage[main]/Dbserver/Service[mariadb]/ensure: current_value stopped, should be running (noop) Info: /Stage[main]/Dbserver/Service[mariadb]: Unscheduling refresh on Service[mariadb] Notice: Class[Dbserver]: Would have triggered 'refresh' from 1 events Notice: Stage[main]: Would have triggered 'refresh' from 1 events Notice: Finished catalog run in 0.47 seconds [root@node12 ~]# puppet apply -v class1.pp Notice: Compiled catalog for node12.test.org in environment production in 0.27 seconds Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false. (at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default') Info: Applying configuration version '1607007569' Notice: /Stage[main]/Dbserver/Service[mariadb]/ensure: ensure changed 'stopped' to 'running' Info: /Stage[main]/Dbserver/Service[mariadb]: Unscheduling refresh on Service[mariadb] Notice: Finished catalog run in 2.76 seconds [root@node12 ~]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:26379 *:* LISTEN 0 128 *:22 *:* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 128 *:27017 *:* LISTEN 0 50 *:3306 *:* LISTEN 0 128 :::80 :::* LISTEN 0 128 :::22 :::* LISTEN 0 100 ::1:25 :::* [root@node12 ~]# systemctl is-enabled mariadb.service enabled [root@node12 ~]#
提示：可以看到在當前系統上執行清單，啓動了mariadb；
類的繼承
類的繼承是子類繼承父類中的所有功能代碼，它可以對父類中的所有屬性進行修改，其定義語法如下
class childer_class_name inherits parent_class_name{
...puppet code ...
}
提示：子類名稱需使用完全限定名稱，比如父類是apache，子類名可以寫成apache::web;類似這種；inherits是關鍵字表示繼承之意，後面加父類名稱；
示例
[root@node12 ~]# cat redis.pp
class redis{
package{"redis":
ensure => installed,
}
service{"redis":
ensure => running,
enable => true,
hasrestart => true,
restart => 'service redis restart',
}
}
class redis::master inherits redis {
file{"/etc/redis.conf":
ensure => file,
source => '/root/redis-master.conf',
}
Service["redis"]{
subscribe => File["/etc/redis.conf"],
restart => 'systemctl restart redis'
}
}
include redis::master
[root@node12 ~]#
提示：以上清單定義了兩個類，一個是父類名爲reids，另一個爲子類名爲redis::master；子類繼承父類，並在其基礎上新增了file資源以及增加了service資源的訂閱關係；
本地redis-master.conf配置文件內容
[root@node12 ~]# cat /root/redis-master.conf bind 0.0.0.0 protected-mode yes port 6379 tcp-backlog 511 timeout 0 tcp-keepalive 300 daemonize no supervised no pidfile /var/run/redis_6379.pid loglevel notice logfile /var/log/redis/redis.log databases 16 save 900 1 save 300 10 save 60 10000 stop-writes-on-bgsave-error yes rdbcompression yes rdbchecksum yes dbfilename dump.rdb dir /var/lib/redis slave-serve-stale-data yes slave-read-only yes repl-diskless-sync no repl-diskless-sync-delay 5 repl-disable-tcp-nodelay no slave-priority 100 appendonly no appendfilename "appendonly.aof" appendfsync everysec no-appendfsync-on-rewrite no auto-aof-rewrite-percentage 100 auto-aof-rewrite-min-size 64mb aof-load-truncated yes lua-time-limit 5000 slowlog-log-slower-than 10000 slowlog-max-len 128 latency-monitor-threshold 0 notify-keyspace-events "" hash-max-ziplist-entries 512 hash-max-ziplist-value 64 list-max-ziplist-size -2 list-compress-depth 0 set-max-intset-entries 512 zset-max-ziplist-entries 128 zset-max-ziplist-value 64 hll-sparse-max-bytes 3000 activerehashing yes client-output-buffer-limit normal 0 0 0 client-output-buffer-limit slave 256mb 64mb 60 client-output-buffer-limit pubsub 32mb 8mb 60 hz 10 aof-rewrite-incremental-fsync yes [root@node12 ~]#
執行清單，看看redis是否會監聽在本機所有地址的6379端口？
[root@node12 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:27017 *:*
LISTEN 0 50 *:3306 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
[root@node12 ~]# puppet apply -v --noop redis.pp
Notice: Compiled catalog for node12.test.org in environment production in 0.32 seconds
Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false.
(at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default')
Info: Applying configuration version '1607008817'
Notice: /Stage[main]/Redis::Master/File[/etc/redis.conf]/content: current_value {md5}cb9ab7d298a50a0de20077de143e3f73, should be {md5}12e59b058c0ef61ad52bcfa2d4de58ff (noop)
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Scheduling refresh of Service[redis]
Notice: Class[Redis::Master]: Would have triggered 'refresh' from 1 events
Notice: /Stage[main]/Redis/Service[redis]/ensure: current_value stopped, should be running (noop)
Info: /Stage[main]/Redis/Service[redis]: Unscheduling refresh on Service[redis]
Notice: Class[Redis]: Would have triggered 'refresh' from 1 events
Notice: Stage[main]: Would have triggered 'refresh' from 2 events
Notice: Finished catalog run in 0.18 seconds
[root@node12 ~]# puppet apply -v redis.pp
Notice: Compiled catalog for node12.test.org in environment production in 0.33 seconds
Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false.
(at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default')
Info: Applying configuration version '1607008824'
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Filebucketed /etc/redis.conf to puppet with sum cb9ab7d298a50a0de20077de143e3f73
Notice: /Stage[main]/Redis::Master/File[/etc/redis.conf]/content: content changed '{md5}cb9ab7d298a50a0de20077de143e3f73' to '{md5}12e59b058c0ef61ad52bcfa2d4de58ff'
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Scheduling refresh of Service[redis]
Notice: /Stage[main]/Redis/Service[redis]/ensure: ensure changed 'stopped' to 'running'
Info: /Stage[main]/Redis/Service[redis]: Unscheduling refresh on Service[redis]
Notice: Finished catalog run in 0.13 seconds
[root@node12 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:6379 *:*
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:27017 *:*
LISTEN 0 50 *:3306 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
[root@node12 ~]#
提示：可以看到redis監聽在本機任何地址的6379端口；
puppet中的模板
puppet中的模板和ansible中的模板功能很類似，主要用在爲一些服務提供配置文件模板，不同於ansible中的模板，puppet中的模板使用的erb模板語言，ansible使用的是jinja2模板語言；在puppet中使用模板的語法如下
file{'title':
ensure => file,
content => template('/PATH/TO/ERB_FILE'),
}
提示：在複製配置文件時，指定源需使用content來指定，並且調用內建函數template來指定要複製的源文件，通常這個源文件就是一個模板配置文件；
在模板文件中使用內嵌的變量替換機制，其語法如下
<%= @VARIABLE_NAME %>
提示：我們需要把要替換的值用上述變量的方式代替即可；
示例：替換redis監聽地址
[root@node12 ~]# grep ^bind redis-master.conf.erb bind <%= @ipaddress %> [root@node12 ~]#
提示：以上內容表示bind 後面的值爲ipaddress這個變量的值；這個變量是fact變量，主要用於存放本機ip地址；
定義資源清單
[root@node12 ~]# cat redis.pp
class redis{
package{"redis":
ensure => installed,
}
service{"redis":
ensure => running,
enable => true,
hasrestart => true,
restart => 'service redis restart',
}
}
class redis::master inherits redis {
file{"/etc/redis.conf":
ensure => file,
content => template('/root/redis-master.conf.erb'),
}
Service["redis"]{
subscribe => File["/etc/redis.conf"],
restart => 'systemctl restart redis'
}
}
include redis::master
[root@node12 ~]#
提示：以上清單在定義配置文件源文件時，指定content屬性爲內建函數template調用/root/redis-master.conf.erb；表示使用這個模板文件覆蓋/etc/redis.conf文件內容；
執行清單，看看對應redis是否監聽在本機192.168.0.52這個地址上呢？
[root@node12 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:6379 *:*
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:27017 *:*
LISTEN 0 50 *:3306 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
[root@node12 ~]# puppet apply -v --noop redis.pp
Notice: Compiled catalog for node12.test.org in environment production in 0.33 seconds
Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false.
(at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default')
Info: Applying configuration version '1607010053'
Notice: /Stage[main]/Redis::Master/File[/etc/redis.conf]/content: current_value {md5}12e59b058c0ef61ad52bcfa2d4de58ff, should be {md5}52397ae299aa46fe4103654abd62f5fd (noop)
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Scheduling refresh of Service[redis]
Notice: Class[Redis::Master]: Would have triggered 'refresh' from 1 events
Notice: /Stage[main]/Redis/Service[redis]: Would have triggered 'refresh' from 1 events
Notice: Class[Redis]: Would have triggered 'refresh' from 1 events
Notice: Stage[main]: Would have triggered 'refresh' from 2 events
Notice: Finished catalog run in 0.12 seconds
[root@node12 ~]# puppet apply -v redis.pp
Notice: Compiled catalog for node12.test.org in environment production in 0.33 seconds
Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false.
(at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default')
Info: Applying configuration version '1607010059'
Info: FileBucket got a duplicate file {md5}12e59b058c0ef61ad52bcfa2d4de58ff
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Filebucketed /etc/redis.conf to puppet with sum 12e59b058c0ef61ad52bcfa2d4de58ff
Notice: /Stage[main]/Redis::Master/File[/etc/redis.conf]/content: content changed '{md5}12e59b058c0ef61ad52bcfa2d4de58ff' to '{md5}52397ae299aa46fe4103654abd62f5fd'
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Scheduling refresh of Service[redis]
Notice: /Stage[main]/Redis/Service[redis]: Triggered 'refresh' from 1 events
Notice: Finished catalog run in 0.15 seconds
[root@node12 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 192.168.0.52:6379 *:*
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:27017 *:*
LISTEN 0 50 *:3306 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
[root@node12 ~]# grep ^bind /etc/redis.conf
bind 192.168.0.52
[root@node12 ~]#
提示：可以看到對應redis已經監聽在192.168.0.52這個地址，並且配置文件中的bing的值也是192.168.0.52；
在模板中使用自定義變量
[root@node12 ~]# grep -Ei "^bind|port" redis-master.conf.erb bind <%= @redis_bindip%> port <%= @redis_port %> [root@node12 ~]#
在資源中定義變量
[root@node12 ~]# cat redis.pp
class redis{
package{"redis":
ensure => installed,
}
service{"redis":
ensure => running,
enable => true,
hasrestart => true,
restart => 'service redis restart',
}
}
class redis::master($redis_bindip='0.0.0.0',$redis_port='6379') inherits redis {
file{"/etc/redis.conf":
ensure => file,
content => template('/root/redis-master.conf.erb'),
}
Service["redis"]{
subscribe => File["/etc/redis.conf"],
restart => 'systemctl restart redis'
}
}
class{"redis::master":
redis_port => '16379',
}
[root@node12 ~]#
提示；在該資源中聲明類時，傳遞了redis_port這個形參的值爲16379，默認的redis_bindip爲0.0.0.0；
執行清單，看看redis是否監聽在本機所有地址的16379端口？
[root@node12 ~]# puppet apply -v redis.pp
Warning: Config file /etc/puppet/hiera.yaml not found, using Hiera defaults
Notice: Compiled catalog for node12.test.org in environment production in 0.38 seconds
Warning: The package type's allow_virtual parameter will be changing its default value from false to true in a future release. If you do not want to allow virtual packages, please explicitly set allow_virtual to false.
(at /usr/share/ruby/vendor_ruby/puppet/type.rb:816:in `set_default')
Info: Applying configuration version '1607010599'
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Filebucketed /etc/redis.conf to puppet with sum 52397ae299aa46fe4103654abd62f5fd
Notice: /Stage[main]/Redis::Master/File[/etc/redis.conf]/content: content changed '{md5}52397ae299aa46fe4103654abd62f5fd' to '{md5}13a04cb20de2d787e0e18c1c13560cab'
Info: /Stage[main]/Redis::Master/File[/etc/redis.conf]: Scheduling refresh of Service[redis]
Notice: /Stage[main]/Redis/Service[redis]: Triggered 'refresh' from 1 events
Notice: Finished catalog run in 0.15 seconds
[root@node12 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:16379 *:*
LISTEN 0 128 *:27017 *:*
LISTEN 0 50 *:3306 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
[root@node12 ~]# grep -Ei "^bind|port" /etc/redis.conf
bind 0.0.0.0
port 16379
[root@node12 ~]#
提示：可以看到對應redis監聽在本機所有地址的16379端口，並且對應配置文件也發生了相應的變量替換；
以上就是puppet的模板中使用變量替換的使用方式，更多erb模板語言的使用，請參考官方文檔https://puppet.com/docs/puppet/7.0/lang_template_erb.html#lang_template_erb；
到此puppet中的變量、正則表達式、流程控制、類和模板的使用和演示就完了；有了這些基本編程元素的存在，使得puppet的資源清單變得靈活和通用，我們可以寫一個資源清單適用幾乎所有的不同的系統；