Returning a Stream in a Promise is an anti-pattern.

async-streams-and-promises.js

/** Method 1.  Use a PassThrough stream */
var PassThrough = require('stream').PassThrough;

function myAsyncContent() {
  var myContentStream = new PassThrough();
  
  var streamPromise = getAsyncInfo().then(function(info) {
    return createStreamFromInfo(info);
  });
  
  streamPromise.then(function(stream) {
    stream.pipe(myContentStream);
  }).catch(function(error) {
    stream.emit('error', error);
  });
  
  return myContentStream;
 
}

/** Method 2. Use the streamcat library (handles Promises/Buffers/Streams for you) 'npm install streamcat --save' */
var streamcat = require('streamcat');
function myAsyncContent() {
  var streamPromise = getAsyncInfo().then(function(info) {
    return createStreamFromInfo(info);
  });
  
  return streamcat([streamPromise]);
}