What is the best way to create a link from an image uploaded by the user?

I am trying to create an app that uses IBM Watson Visual Recognition for sortering waste. Watson runs in the backend (node js) and I wanted to develop the application in Vue.

Watson needs a link to an image, and I was thinking of using firebase in order to create the link when an user uploads an image.

My question is: "Is there a better way to do it, considering that the image and its results should be unique to the user an do not have to persist?"

I do not know much about Visual Recognition and just a little of firebase. So, if there is a way to handle things better, please say. Thanks!

As per the API documentation, you can submit the image to be classified either as a url or as a readstream. https://cloud.ibm.com/apidocs/visual-recognition/visual-recognition-v3?code=node#classify

The sample provided in the API docs makes use of a readstream :

const fs = require('fs');
const VisualRecognitionV3 = require('ibm-watson/visual-recognition/v3');
const { IamAuthenticator } = require('ibm-watson/auth');

const visualRecognition = new VisualRecognitionV3({
  version: '2018-03-19',
  authenticator: new IamAuthenticator({
    apikey: '{apikey}',
  }),
  serviceUrl: '{url}',
});

const classifyParams = {
  imagesFile: fs.createReadStream('./fruitbowl.jpg'),
  owners: ['me'],
  threshold: 0.6,
};

visualRecognition.classify(classifyParams)
  .then(response => {
    const classifiedImages = response.result;
    console.log(JSON.stringify(classifiedImages, null, 2));
  })
  .catch(err => {
    console.log('error:', err);
  });