return promises instead of res.json(data) in node.js

Question

I do a post request to payment_url which is triggered the second block of function. But I can't get anything in the then method, because I don't know how to pass the data back to the resolve function.

cilent call

paypal.request.post(payment_url)
  .then(function(data) {
    resolve(data.paymentID);
  })
  .catch(function(err) {
    reject(err);
  });

server code

paypal.payment.create(create_payment_json, function(error, payment) {
  if (error) {
    //throw error, return the promises too
  } else {
    // return promises but how?
   //if I simply do res.json(payment) it's not going to work.
  }
});

Answer 1

I think you have some concepts wrong.

The server response can not be a Promise, since it's already outside the scope of Javascript. In this case we are already speaking about HTTP requests. The type of the response is specified in the header Content-Type , the types available can be checked here .

In your code you are using json.res() , so you will be sending back to the client a text in JSON format.

If you want to get the response from the server through Promises, that must be implemented in the client.