gistfile1.txt

{
  "AWSTemplateFormatVersion" : "2010-09-09",

  "Parameters" : {
    "InstanceType" : {
      "Description" : "WebServer EC2 instance type",
      "Type" : "String",
      "Default" : "m1.small"
    }
    "KeyName" : {
      "Description" : "The EC2 Key Pair to allow SSH access to the instances",
      "Type" : "String"
    },
    "SwarmSize" : {
    	"Type" : "Number",
      "Default" : "1",
      "MinValue" : "1"
    }
  },

  

    "LocustGroup" : {
      "Type" : "AWS::AutoScaling::AutoScalingGroup",
      "Properties" : {
        "AvailabilityZones" : { "Fn::GetAZs" : ""},
        "LaunchConfigurationName" : { "Ref" : "LaunchConfig" },
        "MinSize" : {"Ref": "SwarmSize"},
        "MaxSize" : {"Ref": "SwarmSize"},
      }
    },

    "LaunchConfig" : {
      "Type" : "AWS::AutoScaling::LaunchConfiguration",
      "Properties" : {
        "KeyName" : { "Ref" : "KeyName" },
        "ImageId" : "ami-something,
        "UserData" : { "Fn::Base64": {"Fn::Join": ["", [
              "#!/bin/bash -v\n",
              "echo 'hello'\n"
        ]]}},
        "SecurityGroups" : [ { "Ref" : "InstanceSecurityGroup" } ],
        "InstanceType" : { "Ref" : "InstanceType" }
      }
    }
}