Terraform AMI Maps
Up until today we had been using a map variable in terraform to choose our ubuntu 14 ami based on region. variable "ubuntu_amis" { description = "Mapping of Ubuntu 14.04 AMIs." default = { ap-northeast-1 = "ami-a25cffa2" ap-southeast-1 = "ami-967879c4" ap-southeast-2 = "ami-21ce8b1b" cn-north-1 = "ami-d44fd2ed" eu-central-1 = "ami-9cf9c281" eu-west-1 = "ami-664b0a11" sa-east-1 = "ami-c99518d4" us-east-1 = "ami-c135f3aa" us-gov-west-1 = "ami-91cfafb2" us-west-1 = "ami-bf3dccfb" us-west-2 = "ami-f15b5dc1" } } We would then set the ami id like so when creating an ec2 instance. ami = "${lookup(var.ubuntu_amis, var.region)}" The problem we ran into is that we now use Ubuntu 16 by default and wanted to expand the ami map to contain its ID’s as well. I quickly discovered that nested maps like the one below work. ...