如何从主机名创建自定义:host_role事实? [英] How can I create a custom :host_role fact from the hostname?

问题描述

我正在寻找一个基于主机名前缀的角色，但遇到了一些问题. Ruby对我来说是新手，尽管我已经进行了广泛的寻找解决方案的工作，但我仍然感到困惑.

I'm looking to create a role based on host name prefix and I'm running into some problems. Ruby is new to me and although I've done extensive searching for a solution, I'm still confused.

主机名看起来像这样:

• work-server-01
• home-server-01

这是我写的:

require 'facter'
Facter.add('host_role') do
setcode do
    hostname_array = Facter.value(:hostname).split('-')
    first_in_array = hostname_array.first
    first_in_array.each do |x|
      if x =~ /^(home|work)/
        role = '"#{x}" server'
    end
    role
end
end

我想在角色分配中使用变量插值，但是我想将case语句和'when'一起使用是不正确的.请记住，我是Ruby的新手.

I'd like to use variable interpolation within my role assignment, but I feel like using a case statement along with 'when' is incorrect. Please keep in mind that I'm new to Ruby.

有人会对我如何实现目标有任何想法吗?

Would anybody have any ideas on how I might achieve my goal?

推荐答案

模式匹配主机名事实

以下是代码的相对DRY重构:

Pattern-Matching the Hostname Fact

The following is a relatively DRY refactoring of your code:

require 'facter'

Facter.add :host_role do
  setcode do
    location = case Facter.value(:hostname)
               when /home/ then $&
               when /work/ then $&
               else 'unknown'
               end
    '%s server' % location
  end
end

通常，它只查找正则表达式匹配项，并将匹配项的值分配给 location ，然后将其作为格式化字符串的一部分返回.

Mostly, it just looks for a regex match, and assigns the value of the match to location which is then returned as part of a formatted string.

在我的系统上，主机名与"home"或"work"都不匹配，所以我正确地得到了:

On my system the hostname doesn't match either "home" or "work", so I correctly get:

Facter.value :host_role
#=> "unknown server"

这篇关于如何从主机名创建自定义:host_role事实?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！