Promise chain continues before inner promise is resolved

by

You’ve done nothing wrong here. This is jQuery’s fault, as so often1.

The problem is that jQuery is not Promises/A+ compatible (until v 3.0), and fails to adopt promises/thenable from other implementations than its own. So when your callbacks do return RSVP promises, jQuery just treats them as values to fulfill with, instead of waiting for them.
You could cast all of your promises to a jQuery deferred and it would work, but you really don’t want that. To get the standard Promise behaviour (as offered by RSVP) to work, you will need to avoid jQuery’s buggy then. This can easily be done:

RSVP.Promise.resolve($.getScript("/_layouts/15/SP.RequestExecutor.js"))
//   ^^^^^^^^^^^^^^^
    .then(patchRequestExecutor)
    .then(function(){
        sourceExecutor = new SP.RequestExecutor(sourceFullUrl);
        targetExecutor = new SP.RequestExecutor(targetList);
    })
    .then(getFileInformation)
    .then(getFileBinaryData)
    .then(copyFileAction)
    …

More Related Contents:

  1. How can I execute array of promises in sequential order?
  2. What is the explicit promise construction antipattern and how do I avoid it?
  3. Aren’t promises just callbacks?
  4. How to access the value of a promise?
  5. Is it bad practice to have a constructor function return a Promise?
  6. Resolve promises one after another (i.e. in sequence)?
  7. Why does .json() return a promise?
  8. Difference between microtask and macrotask within an event loop context
  9. Building a promise chain recursively in javascript – memory considerations
  10. Using async/await with a forEach loop
  11. Caching a promise object in AngularJS service
  12. Return from a promise then()
  13. setting a variable to get return from call back function using promise
  14. What’s the difference between returning value or Promise.resolve from then()
  15. Understanding promises in Node.js
  16. fetch: Reject promise with JSON error object
  17. Promise All with Axios
  18. Why does the Promise constructor need an executor?
  19. Understanding JavaScript promise object
  20. Promises for promises that are yet to be created without using the deferred [anti]pattern
  21. How can I chain these functions together with promises?
  22. How do I handle errors with promises?
  23. Promises: Repeat operation until it succeeds?
  24. Promise.all().then() resolve?
  25. How can I export promise result?
  26. Recursive Promises Not Returning
  27. Promise.then Job execution order
  28. AngularJS Promises, $q, defer
  29. When or who does pass resolve and reject functions to JS promises?
  30. When is the body of a Promise constructor callback executed?

Leave a Comment