CloudFormation Launch EC2 instance bare-minimum template

{
  "AWSTemplateFormatVersion" : "2010-09-09",
  "Parameters" : {
    "KeyName": {
      "Description" : "Name of an existing EC2 KeyPair to enable SSH access to the instance",
      "Type": "AWS::EC2::KeyPair::KeyName",
      "ConstraintDescription" : "Can contain only ASCII characters."
    },
    "InstanceType" : {
      "Description" : "WebServer EC2 instance type",
      "Type" : "String",
      "Default" : "m1.small",
      "AllowedValues" : [ "t1.micro", "t2.micro", "t2.small", "t2.medium", "m1.small", "m1.medium", "m1.large", "m1.xlarge", "m2.xlarge", "m2.2xlarge", "m2.4xlarge", "m3.medium", "m3.large", "m3.xlarge", "m3.2xlarge", "c1.medium", "c1.xlarge", "c3.large", "c3.xlarge", "c3.2xlarge", "c3.4xlarge", "c3.8xlarge", "g2.2xlarge", "r3.large", "r3.xlarge", "r3.2xlarge", "r3.4xlarge", "r3.8xlarge", "i2.xlarge", "i2.2xlarge", "i2.4xlarge", "i2.8xlarge", "hi1.4xlarge", "hs1.8xlarge", "cr1.8xlarge", "cc2.8xlarge", "cg1.4xlarge"],
      "ConstraintDescription" : "Must be a valid EC2 instance type"
    },
    "Subnet": {
      "Type": "AWS::EC2::Subnet::Id",
      "Description": "Subnet to launch the instance into."
    },
    "VPC": {
      "Type": "AWS::EC2::VPC::Id",
      "Description": "VPC to launch the instance into."
    },
    "SSHLocation" : {
      "Description" : "The IP address range that can be used to SSH to the EC2 instances",
      "Type": "String",
      "MinLength": "9",
      "MaxLength": "18",
      "Default": "0.0.0.0/0",
      "AllowedPattern": "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})/(\\d{1,2})",
      "ConstraintDescription": "Must be a valid IP CIDR range of the form x.x.x.x/x"
    }
  },
  "Mappings" : {
    "AWSInstanceType2Arch" : {
      "t1.micro"    : { "Arch" : "PV64"   },
      "t2.micro"    : { "Arch" : "HVM64"  },
      "t2.small"    : { "Arch" : "HVM64"  },
      "t2.medium"   : { "Arch" : "HVM64"  },
      "m1.small"    : { "Arch" : "PV64"   },
      "m1.medium"   : { "Arch" : "PV64"   },
      "m1.large"    : { "Arch" : "PV64"   },
      "m1.xlarge"   : { "Arch" : "PV64"   },
      "m2.xlarge"   : { "Arch" : "PV64"   },
      "m2.2xlarge"  : { "Arch" : "PV64"   },
      "m2.4xlarge"  : { "Arch" : "PV64"   },
      "m3.medium"   : { "Arch" : "HVM64"  },
      "m3.large"    : { "Arch" : "HVM64"  },
      "m3.xlarge"   : { "Arch" : "HVM64"  },
      "m3.2xlarge"  : { "Arch" : "HVM64"  },
      "c1.medium"   : { "Arch" : "PV64"   },
      "c1.xlarge"   : { "Arch" : "PV64"   },
      "c3.large"    : { "Arch" : "HVM64"  },
      "c3.xlarge"   : { "Arch" : "HVM64"  },
      "c3.2xlarge"  : { "Arch" : "HVM64"  },
      "c3.4xlarge"  : { "Arch" : "HVM64"  },
      "c3.8xlarge"  : { "Arch" : "HVM64"  },
      "g2.2xlarge"  : { "Arch" : "HVMG2"  },
      "r3.large"    : { "Arch" : "HVM64"  },
      "r3.xlarge"   : { "Arch" : "HVM64"  },
      "r3.2xlarge"  : { "Arch" : "HVM64"  },
      "r3.4xlarge"  : { "Arch" : "HVM64"  },
      "r3.8xlarge"  : { "Arch" : "HVM64"  },
      "i2.xlarge"   : { "Arch" : "HVM64"  },
      "i2.2xlarge"  : { "Arch" : "HVM64"  },
      "i2.4xlarge"  : { "Arch" : "HVM64"  },
      "i2.8xlarge"  : { "Arch" : "HVM64"  },
      "hi1.4xlarge" : { "Arch" : "HVM64"  },
      "hs1.8xlarge" : { "Arch" : "HVM64"  },
      "cr1.8xlarge" : { "Arch" : "HVM64"  },
      "cc2.8xlarge" : { "Arch" : "HVM64"  }
    },
    "AWSRegionArch2AMI" : {
      "us-east-1"      : { "PV64" : "ami-50842d38", "HVM64" : "ami-08842d60", "HVMG2" : "ami-3a329952"  },
      "us-west-2"      : { "PV64" : "ami-af86c69f", "HVM64" : "ami-8786c6b7", "HVMG2" : "ami-47296a77"  },
      "us-west-1"      : { "PV64" : "ami-c7a8a182", "HVM64" : "ami-cfa8a18a", "HVMG2" : "ami-331b1376"  },
      "eu-west-1"      : { "PV64" : "ami-aa8f28dd", "HVM64" : "ami-748e2903", "HVMG2" : "ami-00913777"  },
      "ap-southeast-1" : { "PV64" : "ami-20e1c572", "HVM64" : "ami-d6e1c584", "HVMG2" : "ami-fabe9aa8"  },
      "ap-northeast-1" : { "PV64" : "ami-21072820", "HVM64" : "ami-35072834", "HVMG2" : "ami-5dd1ff5c"  },
      "ap-southeast-2" : { "PV64" : "ami-8b4724b1", "HVM64" : "ami-fd4724c7", "HVMG2" : "ami-e98ae9d3"  },
      "sa-east-1"      : { "PV64" : "ami-9d6cc680", "HVM64" : "ami-956cc688", "HVMG2" : "NOT_SUPPORTED" },
      "cn-north-1"     : { "PV64" : "ami-a857c591", "HVM64" : "ami-ac57c595", "HVMG2" : "NOT_SUPPORTED" },
      "eu-central-1"   : { "PV64" : "ami-a03503bd", "HVM64" : "ami-b43503a9", "HVMG2" : "ami-b03503ad"  }
    }
  },
  "Resources" : {
    "WebServerInstance": {
      "Type": "AWS::EC2::Instance",
      "Properties": {
        "ImageId" : { "Fn::FindInMap" : [ "AWSRegionArch2AMI", { "Ref" : "AWS::Region" },
                          { "Fn::FindInMap" : [ "AWSInstanceType2Arch", { "Ref" : "InstanceType" }, "Arch" ] } ] },
        "InstanceType"   : { "Ref" : "InstanceType" },
        "SecurityGroupIds" : [ {"Ref" : "WebServerSecurityGroup"} ],
        "SubnetId": {"Ref": "Subnet"},
        "KeyName"        : { "Ref" : "KeyName" },
        "UserData" : { "Fn::Base64" : { "Fn::Join" : ["\n", [
            "#!/bin/bash",
            "apt-get update",
            "apt-get install apache2"
            ]]
          }
        }
      }
    },
    "WebServerSecurityGroup" : {
      "Type" : "AWS::EC2::SecurityGroup",
      "Properties" : {
        "GroupDescription" : "Enable HTTP access via port 80",
        "SecurityGroupIngress" : [
          {"IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "CidrIp" : "0.0.0.0/0"},
          {"IpProtocol" : "tcp", "FromPort" : "22", "ToPort" : "22", "CidrIp" : { "Ref" : "SSHLocation"}}
        ],
        "VpcId" : {"Ref" : "VPC"}
      }
    }
  }
}