AWS CloudFormation
User Guide (API Version 2010-05-15)

Pseudo Parameters Reference

Pseudo parameters are parameters that are predefined by AWS CloudFormation. You do not declare them in your template. Use them the same way as you would a parameter, as the argument for the Ref function.


The following snippet assigns the value of the AWS::Region pseudo parameter to an output value:


"Outputs" : { "MyStacksRegion" : { "Value" : { "Ref" : "AWS::Region" } } }


Outputs: MyStacksRegion: Value: !Ref "AWS::Region"


Returns the AWS account ID of the account in which the stack is being created, such as 123456789012.


Returns the list of notification Amazon Resource Names (ARNs) for the current stack.

To get a single ARN from the list, use Fn::Select.


"myASGrpOne" : { "Type" : "AWS::AutoScaling::AutoScalingGroup", "Version" : "2009-05-15", "Properties" : { "AvailabilityZones" : [ "us-east-1a" ], "LaunchConfigurationName" : { "Ref" : "MyLaunchConfiguration" }, "MinSize" : "0", "MaxSize" : "0", "NotificationConfigurations" : [{ "TopicARN" : { "Fn::Select" : [ "0", { "Ref" : "AWS::NotificationARNs" } ] }, "NotificationTypes" : [ "autoscaling:EC2_INSTANCE_LAUNCH", "autoscaling:EC2_INSTANCE_LAUNCH_ERROR" ] }] } }


myASGrpOne: Type: AWS::AutoScaling::AutoScalingGroup Version: '2009-05-15' Properties: AvailabilityZones: - "us-east-1a" LaunchConfigurationName: Ref: MyLaunchConfiguration MinSize: '0' MaxSize: '0' NotificationConfigurations: - TopicARN: Fn::Select: - '0' - Ref: AWS::NotificationARNs NotificationTypes: - autoscaling:EC2_INSTANCE_LAUNCH - autoscaling:EC2_INSTANCE_LAUNCH_ERROR


Removes the corresponding resource property when specified as a return value in the Fn::If intrinsic function.

For example, you can use the AWS::NoValue parameter when you want to use a snapshot for an Amazon RDS DB instance only if a snapshot ID is provided. If the UseDBSnapshot condition evaluates to true, AWS CloudFormation uses the DBSnapshotName parameter value for the DBSnapshotIdentifier property. If the condition evaluates to false, AWS CloudFormation removes the DBSnapshotIdentifier property.


"MyDB" : { "Type" : "AWS::RDS::DBInstance", "Properties" : { "AllocatedStorage" : "5", "DBInstanceClass" : "db.m1.small", "Engine" : "MySQL", "EngineVersion" : "5.5", "MasterUsername" : { "Ref" : "DBUser" }, "MasterUserPassword" : { "Ref" : "DBPassword" }, "DBParameterGroupName" : { "Ref" : "MyRDSParamGroup" }, "DBSnapshotIdentifier" : { "Fn::If" : [ "UseDBSnapshot", {"Ref" : "DBSnapshotName"}, {"Ref" : "AWS::NoValue"} ] } } }


MyDB: Type: AWS::RDS::DBInstance Properties: AllocatedStorage: '5' DBInstanceClass: db.m1.small Engine: MySQL EngineVersion: '5.5' MasterUsername: Ref: DBUser MasterUserPassword: Ref: DBPassword DBParameterGroupName: Ref: MyRDSParamGroup DBSnapshotIdentifier: Fn::If: - UseDBSnapshot - Ref: DBSnapshotName - Ref: AWS::NoValue


Returns the partition that the resource is in. For standard AWS regions, the partition is aws. For resources in other partitions, the partition is aws-partitionname. For example, the partition for resources in the China (Beijing) region is aws-cn.


Returns a string representing the AWS Region in which the encompassing resource is being created, such as us-west-2.


Returns the ID of the stack as specified with the aws cloudformation create-stack command, such as arn:aws:cloudformation:us-west-2:123456789012:stack/teststack/51af3dc0-da77-11e4-872e-1234567db123.


Returns the name of the stack as specified with the aws cloudformation create-stack command, such as teststack.


Returns the suffix for a domain. The suffix is typically, but might differ by region. For example, the suffix for the China (Beijing) region is