我怎样才能创建Cloudformation模板参数IAM角色下拉

Question

我正在寻找一种方式，列出在Cloudformation模板的现有IAM角色以类似的方式，以上市说EC2密钥对。下面是什么，我既EC2密钥对和IAM角色试图然而Cloudformation抛出一个错误，指出“角色名”不存在的例子。

"KeyName": { 
    "Description" : "Choose a Key Pair that is available in this region", 
    "Type": "AWS::EC2::KeyPair::KeyName", 
    "ConstraintDescription": "Must be the name of an existing EC2 Key Pair" 
}, 
"ServiceRole": { 
    "Description" : "Choose an IAM Role that is available in this region", 
    "Type": "AWS::IAM::Role::RoleName", 
    "ConstraintDescription": "Must be the name of an existing IAM Role" 
}, 

Screenshot of Cloudformation Interface 任何想法，如果这是可能实现的？

Answer 1

并非所有类型在下拉列表的支持，IAM角色是不支持的类型。所以你无法获得IAM角色的下拉菜单。相反，你将不得不使用一个简单的文本框。

这里是一个支持的参数类型的当前列表：

• String
• Number
• List<Number>
• CommaDelimitedList
• AWS::EC2::AvailabilityZone::Name
• AWS::EC2::Image::Id
• AWS::EC2::Instance::Id
• AWS::EC2::KeyPair::KeyName
• AWS::EC2::SecurityGroup::GroupName
• AWS::EC2::SecurityGroup::Id
• AWS::EC2::Subnet::Id
• AWS::EC2::Volume::Id
• AWS::EC2::VPC::Id
• AWS::Route53::HostedZone::Id
• List<AWS::EC2::AvailabilityZone::Name>
• List<AWS::EC2::Image::Id>
• List<AWS::EC2::Instance::Id>
• List<AWS::EC2::SecurityGroup::GroupName>
• List<AWS::EC2::SecurityGroup::Id>
• List<AWS::EC2::Subnet::Id>
• List<AWS::EC2::Volume::Id>
• List<AWS::EC2::VPC::Id>
• List<AWS::Route53::HostedZone::Id>

来源：http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/parameters-section-structure.html