Attempting to use Wiremock standalone with global response templating to dynamically map an input value (user id) with a response value (username).

This repo is set up to demonstrate the issue I'm coming up against: unable to fetch a value from transformerParameters.* dynamically.

This repo serves mainly the purpose of referencing it in a Stack Overflow question.

My goal is to populate the username field in the JSON response based dynamically on the input user ID, by using the JSON map under transformerParameters.usernameMapping.

I have tried:

• {{parameters.usernameMapping.2}} <-- works but hardcoded so does not solve our problem
• {{parameters.usernameMapping[request.pathSegments.[1]]}} <-- breaks
• {{parameters.usernameMapping[{{request.pathSegments.[1]}}]}} <-- breaks
• {{parameters.usernameMapping.{{request.pathSegments.[1]}}}} <-- breaks
• {{parameters.usernameMapping.[userId]}} <-- (userId assigned previously) does not break but prints nothing

Use lookup in this manner:

• {{lookup parameters.usernameMapping userId}}

You can view the mapping here.

You can call the stub via curl using:

curl --location --request GET 'http://localhost:8080/users/1' \
    --header 'Accept: application/json'

To run this, assuming you have Docker (Compose): docker compose up -d (it will bind to port 8080).

I am trying to resolve this without having to write custom extensions to Wiremock, and I am wondering what I might be missing here.

EOF