I have requirement to wait for file to be present before executing next steps

Question

Hi Team

I have a simple use case we have an organization provided soe and want to do customisation on top of that. Its a windows machine, so org specific bootstrap does some restart and once it completes , a file gets created in C: drive.

I need to make sure that my customization runs after the organisation specific bootstrap is completed.

I have this in userdata
UserData: 
          Fn::Base64: !Sub | 
            
            cfn-init.exe -v --stack ${AWS::StackName} --resource CPMLaunchTemplate --configsets full-install --region ${AWS::Region}

and myconfigset looks like this
 Metadata:
      AWS::CloudFormation::Init:
        configSets:
          full-install:
             - waitForBootstrap
            - configureWindowsDrive

waitForBootstrap:
            1-deploy-wait-for-bootstrap:
              command: powershell.exe -command "while(-Not (Test-Path C:\bootstrap-complete.txt)) { Write-Host 'Waiting for file to be present';  Start-Sleep -Seconds 5 }"

configureWindowsDrive:    
          commands:
            downloadDriveMappingFile:
              command: !Sub
..
.

Somehow my script isnt waiting forfile to be present an dmoving to next step of ConfigureWindowsDrive.

Not sue what i am doing wrong an how can i get that fixed.

Duane · Answer

Hello,

The provided PowerShell command works locally on a Windows machine, however the following needs to be remembered:

"Because paths on Windows use a backslash ('\') character, you must always remember to properly escape all backslashes by prepending another backslash whenever you refer to a Windows path in the AWS CloudFormation template." [1]

You will need to update your waitForBootstrap as follows:

```
    waitForBootstrap:
        1-deploy-wait-for-bootstrap:
          command: powershell.exe -command "while(-Not (Test-Path C:\bootstrap-complete.txt)) { Write-Host 'Waiting for file to be present';  Start-Sleep -Seconds 5 }"
```

[1] https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-windows-stacks-bootstrapping.html

I have requirement to wait for file to be present before executing next steps

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