How to reference AWS Transfer Family Workflow named variables like ${transfer:HomeDirectory} and ${transfer:HomeFolder} in Decrypt file workflow?

Question

The current AWS Transfer Family Workflows allow for using `${transfer:UserName}` and `${transfer:UploadDate}` 
ref: https://docs.aws.amazon.com/transfer/latest/userguide/nominal-steps-workflow.html

Is it possible to reference the variables that are available when creating transfer policies `${transfer:HomeBucket}`, `${transfer:HomeDirectory}`, `${transfer:HomeFolder}`, `${transfer:UserName}` in the destination key prefix for the Decrypt file workflow?
 ref: https://docs.aws.amazon.com/transfer/latest/userguide/users-policies.html

The goal is to decrypt a file with the Decrypt file workflow and output the decrypted file in the same directory as the original file. So if it is not possible, is there a recommended way to output the decrypted file in the same directory as the original file that is based on the users `${transfer:HomeDirectory}`?
ref:  https://docs.aws.amazon.com/transfer/latest/userguide/nominal-steps-workflow.html#decrypt-step-details

Accepted Answer

Hi! Currently, it is not possible to reference the variables such as ${transfer:HomeBucket}, ${transfer:HomeDirectory}, ${transfer:HomeFolder} in the destination key prefix for the Decrypt file workflow step. Until this is supported natively, you might potentially develop a workaround such as a mapping table between usernames and their home bucket/directory/folder info, and invoke a lambda function via Custom Workflow Step that routes decrypted files based on that username to destination mapping. More details on the Custom Workflow Step can be found in the documentation here - https://docs.aws.amazon.com/transfer/latest/userguide/custom-step-details.html

How to reference AWS Transfer Family Workflow named variables like ${transfer:HomeDirectory} and ${transfer:HomeFolder} in Decrypt file workflow?

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