Vagrant 使用默认变量的打包器？

我一直在想在packer中使用选项变量的可能性， 我的脚本如下：

"provisioners": [{
  "type": "shell",
  "scripts": [
    "scripts/centos/5.11/puppet-{{user `config`}}.sh",
  ]
}],
"variables": {
  "config": "{{user `type`}} | slave",
} 

典型的命令是：

packer build              \
    -var 'config=master'  \
    template.json

"provisioners": [{
   "type": "shell",
   "scripts": [
      "scripts/centos/5.11/puppet-{{user `config`}}.sh"
   ]
}],
"variables": {
  "config": "slave"
} 

但也能做到以下几点：

packer build template.json # were config would default to slave

---

命令行变量覆盖json模板中的设置。见包装商文件：

因此，只需在模板中设置默认值，并使用您已经使用的命令行示例进行覆盖

您的模板将是：

packer build              \
    -var 'config=master'  \
    template.json

"provisioners": [{
   "type": "shell",
   "scripts": [
      "scripts/centos/5.11/puppet-{{user `config`}}.sh"
   ]
}],
"variables": {
  "config": "slave"
}