Setting Up Gateway for Dynamic API Source that use a Function

Does anyone know how I could setup a datasource in a gateway that uses a dynamic API source?

I currently have a function in the desktop version that uses a table column to supply the parameters to an API source.

Function:

Source = Json.Document(Web.Contents("https://test.net/rest/api/2/issue/"& IssueParam &"/changelog?maxResults=1000"))

Issue Table:

A calculated column ( Function([IssueID]) ) uses the IssueID column to bring in values using the API function.