AWS CloudFormation WaitCondition example

CloudFormation is a great tool for spinning up EC2 instances and the like.

Here is an example of using a wait condition for waiting until a Windows 2012 R2 Base service has started.  Please excuse the designer JSON.  I was using it to validate the JSON correctness.

{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Resources": {
    "YourInstanceId": {
      "Type": "AWS::EC2::Instance",
      "Properties": {
        "DisableApiTermination": "false",
        "InstanceInitiatedShutdownBehavior": "stop",
        "ImageId": "ami-dfccd1ef",
        "KeyName": "YourKeyName",
        "Monitoring": "false",
        "Tags": [
          {
            "Key": "Name",
            "Value": "NameOfYourInstance"
          }
        ],
        "NetworkInterfaces": [
          {
            "DeleteOnTermination": "true",
            "DeviceIndex": 0,
            "SubnetId": "yourSubnetId",
            "GroupSet": [
              "yourSecurityGroupId"
            ],
            "AssociatePublicIpAddress": "true"
          }
        ],
"UserData": {
          "Fn::Base64": {
            "Fn::Join": [
              "",
              [
                "<powershell>\n",
                "Start-Service BITS \n",
"$arrService = Get-Service BITS \n",
"$returnCode = 1 \n",
"if ($arrService.Status -eq 'running'){ $returnCode = 0 } \n",
"while($arrService.Status -ne 'running') \n",
"{ \n",
"Start-Sleep -s 5 \n",
"$arrService = Get-Service BITS \n",
"if ($arrService.Status -eq 'running'){ $returnCode = 0 } \n",
"} \n",
                "cfn-signal.exe -e $returnCode ",
                {
                  "Fn::Base64": {
                    "Ref": "WaitHandle"
                  }
                },
                "\n",
                "</powershell> \n",
                "<persist>true</persist>"
              ]
            ]
          }
        }
      }
    },
    "WaitCondition": {
      "Type": "AWS::CloudFormation::WaitCondition",
      "DependsOn" : "instancei1c92e0da",
      "Properties": {
        "Handle" : { "Ref" : "WaitHandle" },
        "Timeout" : "300"
      },
      "Metadata": {
        "AWS::CloudFormation::Designer": {
          "id": "b0f248b8-89a7-4b6b-881a-ef79dd677322"
        }
      }
    },
    "WaitHandle": {
      "Type": "AWS::CloudFormation::WaitConditionHandle",
      "Properties": {},
      "Metadata": {
        "AWS::CloudFormation::Designer": {
          "id": "1f0d4b0b-1971-4e5d-9b2c-5472c764dc92"
        }
      }
    }
  },
  "Description": ""
}

The BITS service was used here since it's a built-in Windows service.  It could be whatever service that you would like to start and verify that it started.

CloudFormation seems good overall.  It would be nice to have a local validator for it and / or a way to test the templates locally first.

I'd like to explore the Vagrant AWS provider when I have time (heard that there might be bugs though regarding Windows).  Please feel free to comment and share your experiences.  Cheers.