ami-lookup

Lambda function for the lookup of the latest ami ID for amazon-linux, ubuntu, and windows >= 2012 R2 from public AWS AMI libraries

Use in cloudformation

Add parameters to your cloudformation template

Instance Type, you'll need this for the ami lookup function and your EC2 Instance or EC2 LaunchConfiguration

  InstanceType:
    Description: Amazon EC2 instance type
    Type: String
    AllowedValues:
    - t1.micro
    - t2.micro
    - t2.small
    - t2.medium
    ConstraintDescription: Must be a valid EC2 instance type.

OSVersion, you'll need this for the ami lookup function

  OSVersion:
    Description: The Operating System to look up the AMI for
    Type: String
    AllowedValues:
    - linux-amazon
    - linux-ubuntu-trusty
    - linux-ubuntu-xenial
    - linux-ubuntu-yakkety
    - linux-ubuntu-zesty
    - windows-2008-r2-64-bit
    - windows-2012-r2-64-bit
    - windows-2016-64-bit-core
    - windows-2016-64-bit-full

Include the AMI Lookup function as a CustomResource in your template

  AMILookup:
    Type: AWS::CloudFormation::CustomResource
    Properties:
      ServiceToken: arn:aws:lambda:aws-region:XXXXXXXXXX:function:ami-lookup
      Region: !Sub ${AWS::Region}
      OSName: windows
      Architecture: !Ref OSVersion

Note: Replace the ServiceToken attribute value with the arn of the AMI lookup function in your AWS account

Use the AMILookup CustomResource in your EC2 Instance or LaunchConfiguration

  EC2Instance:
    Type: AWS::EC2::Instance
    Properties:
      ImageId: !GetAtt AMILookup.Id
      InstanceType: !Ref InstanceType

  LaunchConfiguration:
    Type: AWS::EC2::LaunchConfiguration
    Properties:
      ImageId: !GetAtt AMILookup.Id
      InstanceType: !Ref InstanceType