Mappings - AWS CloudFormation
语法示例相关资源

Mappings

可选的 Mappings 部分将密钥与对应的一组命名值相匹配。例如，如果您想根据区域设置值，您可以创建将区域名称用作密钥且其中含有您想为每个特定区域指定的值的映射。您使用 Fn::FindInMap 内部函数来检索映射中的值。

不得在 Mappings 部分包含参数、伪参数或内部函数。

语法

Mappings 部分包括键名称 Mappings。映射中的键必须为文字字符串。值可以是 String 或 List 类型。以下示例显示了 Mappings 部分，其中包含一个名为 Mapping01 (逻辑名称) 的映射。

在映射中，每个映射是一个键，后跟另一个映射。键必须是名称/值对映射，且在映射中必须唯一。

JSON

"Mappings" : {
  "Mapping01" : {
    "Key01" : {
      "Name" : "Value01"
    },
    "Key02" : {
      "Name" : "Value02"
    },
    "Key03" : {
      "Name" : "Value03"
    }
  }
}

YAML

Mappings: 
  Mapping01: 
    Key01: 
      Name: Value01
    Key02: 
      Name: Value02
    Key03: 
      Name: Value03

示例

基本映射

以下示例显示的是带映射 Mappings 的 RegionMap 部分，该映射包含五个映射到含单字符串值的名称-值对的密钥。密钥为区域名称。每个名称值对都是该键所表示区域内的 T 系列中可用的一种实例类型。

名称值对中有一个名称（示例中的 InstanceType）和一个值。您可以通过给值命名以将多组值映射到密钥中。

JSON

"Mappings" : {
  "RegionMap" : {
    "us-east-1"      : {"InstanceType": "t2.micro"},
    "us-west-1"      : {"InstanceType": "t2.micro"},
    "eu-west-1"      : {"InstanceType": "t2.micro"},
    "eu-north-1"     : {"InstanceType": "t3.micro"},
    "me-south-1"     : {"InstanceType": "t3.micro"}
  }
}

YAML

Mappings:
  RegionMap:
    us-east-1:
      InstanceType: t2.micro
    us-west-1:
      InstanceType: t2.micro
    eu-west-1:
      InstanceType: t2.micro
    eu-north-1:
      InstanceType: t3.micro
    me-south-1:
      InstanceType: t3.micro

带有多个值的映射

以下示例演示了映射到两组值的区域键：一个名为 MyAMI1，另一个名为 MyAMI2。

JSON

    "AMIIDMap" : {
      "us-east-1"        : {"MyAMI1" : "ami-0ff8a91507f77f867", "MyAMI2" : "ami-0a584ac55a7631c0c"},
      "us-west-1"        : {"MyAMI1" : "ami-0bdb828fd58c52235", "MyAMI2" : "ami-066ee5fd4a9ef77f1"},
      "eu-west-1"        : {"MyAMI1" : "ami-047bb4163c506cd98", "MyAMI2" : "ami-0a7c483d527806435"},
      "ap-southeast-1"   : {"MyAMI1" : "ami-08569b978cc4dfa10", "MyAMI2" : "ami-0be9df32ae9f92309"},
      "ap-northeast-1"   : {"MyAMI1" : "ami-06cd52961ce9f0d85", "MyAMI2" : "ami-053cdd503598e4a9d"}
    }

YAML

AMIIDMap: 
    us-east-1:
      MyAMI1: ami-0ff8a91507f77f867
      MyAMI2: ami-0a584ac55a7631c0c
    us-west-1:
      MyAMI1: ami-0bdb828fd58c52235
      MyAMI2: ami-066ee5fd4a9ef77f1
    eu-west-1:
      MyAMI1: ami-047bb4163c506cd98
      MyAMI2: ami-0a7c483d527806435
    ap-southeast-1:
      MyAMI1: ami-08569b978cc4dfa10
      MyAMI2: ami-0be9df32ae9f92309
    ap-northeast-1:
      MyAMI1: ami-06cd52961ce9f0d85
      MyAMI2: ami-053cdd503598e4a9d

从映射返回值

您可以使用 Fn::FindInMap 函数根据指定的密钥返回命名的值。以下示例模板包含由 FindInMap 函数分配其 ImageId 属性的 Amazon EC2 资源。FindInMap 函数将键指定为创建堆栈的区域（使用 AWS::Region 伪参数），并将 MyAMI1 指定为要映射到的值的名称。有关伪参数的更多信息，请参阅伪参数参考。

JSON

{
  "AWSTemplateFormatVersion" : "2010-09-09",
  "Mappings" : {
    "AMIIDMap" : {
      "us-east-1"        : {"MyAMI1" : "ami-0ff8a91507f77f867", "MyAMI2" : "ami-0a584ac55a7631c0c"},
      "us-west-1"        : {"MyAMI1" : "ami-0bdb828fd58c52235", "MyAMI2" : "ami-066ee5fd4a9ef77f1"},
      "eu-west-1"        : {"MyAMI1" : "ami-047bb4163c506cd98", "MyAMI2" : "ami-0a7c483d527806435"},
      "ap-northeast-1"   : {"MyAMI1" : "ami-06cd52961ce9f0d85", "MyAMI2" : "ami-053cdd503598e4a9d"},
      "ap-southeast-1"   : {"MyAMI1" : "ami-08569b978cc4dfa10", "MyAMI2" : "ami-0be9df32ae9f92309"}
    }
  },
  "Resources" : {
    "myEC2Instance" : {
      "Type" : "AWS::EC2::Instance",
      "Properties" : {
        "ImageId" : { "Fn::FindInMap" : [ "AMIIDMap", { "Ref" : "AWS::Region" }, "MyAMI1" ]},
        "InstanceType" : "t2.micro"
      }
    }
  }
}

YAML

AWSTemplateFormatVersion: "2010-09-09"
Mappings: 
  AMIIDMap: 
    us-east-1:
      MyAMI1: ami-0ff8a91507f77f867
      MyAMI2: ami-0a584ac55a7631c0c
    us-west-1:
      MyAMI1: ami-0bdb828fd58c52235
      MyAMI2: ami-066ee5fd4a9ef77f1
    eu-west-1:
      MyAMI1: ami-047bb4163c506cd98
      MyAMI2: ami-0a7c483d527806435
    ap-northeast-1:
      MyAMI1: ami-06cd52961ce9f0d85
      MyAMI2: ami-053cdd503598e4a9d
    ap-southeast-1:
      MyAMI1: ami-08569b978cc4dfa10
      MyAMI2: ami-0be9df32ae9f92309
Resources: 
  myEC2Instance: 
    Type: "AWS::EC2::Instance"
    Properties: 
      ImageId: !FindInMap [AMIIDMap, !Ref "AWS::Region", MyAMI1]
      InstanceType: t2.micro

输入参数和 Fn::FindInMap

您可以对 Fn::FindInMap 函数使用输入参数来引用映射中的特定值。例如，假定您有一个映射到特定安全组 ID 的区域和环境类型的列表。您可以使用输入参数（EnvironmentType）来选择堆栈使用的安全组 ID。要确定区域，您可以使用 AWS::Region 伪参数，该参数用于获取创建堆栈时所在的亚马逊云科技区域。

JSON

{
  "AWSTemplateFormatVersion" : "2010-09-09",
  "Parameters":{
    "EnvironmentType":{
      "Description":"The environment type (Dev or Prod)",
      "Type":"String",
      "Default":"Dev",
      "AllowedValues":[
        "Dev",
        "Prod"
      ]
    }
  },
  "Mappings":{
    "SecurityGroupMap":{
      "us-east-1": {
        "Dev": "sg-12345678",
        "Prod": "sg-abcdef01"
      },
      "us-west-2" : {
        "Dev" : "sg-ghijkl23",
        "Prod" : "sg-45678abc"
      }
    }
  },
  "Resources":{
    "Ec2Instance":{
      "Type":"AWS::EC2::Instance",
      "Properties":{
        "ImageId": "ami-0a70b9d193ae8a799",
        "InstanceType": "t2.micro",
        "SecurityGroupIds": [{ "Fn::FindInMap" : [ "SecurityGroupMap", { "Ref" : "AWS::Region" }, { "Ref" : "EnvironmentType" } ]}]
      }
    }
  }
}

YAML

AWSTemplateFormatVersion: "2010-09-09"
Parameters: 
  EnvironmentType: 
    Description: The environment type (Dev or Prod)
    Type: String
    Default: Dev
    AllowedValues: 
      - Dev
      - Prod
Mappings: 
  SecurityGroupMap: 
    us-east-1: 
      Dev: "sg-12345678"
      Prod: "sg-abcdef01"
    us-west-2: 
      Dev: "sg-ghijkl23"
      Prod: "sg-45678abc"
Resources:
  Ec2Instance:
    Type: 'AWS::EC2::Instance'
    Properties:
      ImageId: ami-0a70b9d193ae8a799
      InstanceType: t2.micro
      SecurityGroupIds:
        - !FindInMap [SecurityGroupMap, !Ref "AWS::Region", !Ref EnvironmentType]

在开发使用 Fn::FindInMap 函数的模板时，这些相关主题可能对您有所帮助。