You don't say whether you need this on the client or the server.
If it's on the server, your requirement is satisfied using standard Meteor "sync-style" coding - as long as you use Meteor's
HTTP package* for your downloading (the non-callback form).
async/await) seem to be a good alternative, but I don't believe will address your requirement directly. So, if you need this on the client or want to use Promises on the server you will need to use something like
* or wrap a 3rd party function with