how to use redux-saga with async callback function

Question

I want to use redux-saga yield call effect with async function that get the result of this function is call back. ( in this case fingerprintjs but it's general case)

This is the async function I want to exactue :

new Fingerprint2().get(function(result, components) {
console.log(result) // a hash, representing your device fingerprint
console.log(components) // an array of FP components
})

The issue that I want to execute this function via saga , but it's always stuck on yield call.

I try many ways :

import Fingerprint2 from 'fingerprintjs2';

const func = new Fingerprint2().get;
const res = yield call(func);

Also try like this:

import Fingerprint2 from 'fingerprintjs2';

const func = new Fingerprint2().get;
const a = yield call(func, (fingerprint, result) => ({
  fingerprint,
  result
}));

And like this:

import Fingerprint2 from 'fingerprintjs2';

let res = yield call(new Fingerprint2().get(), (fingerprint, result) => ({
  fingerprint,
  result
}));

Any one know about idea or some way to acheive my goal ?

Thanks!

Answer 1

To anyone want answer to the question , there is serval options:

with cps:

const { result, components } = yield cps(cb => new Fingerprint2().get((result, components) => cb(null, { result, components })))

with promise:

 function* rootSaga(){
// Wrapping you function into a promise
const promise = new Promise((resolve, reject) => {
  new Fingerprint2().get((result, components) => {
  resolve({ result, components })
})
})

 // Yield the promise And redux-saga will return the resolved value when the promise resolves
 const { result, components } = yield promise
// do some stuff about  result and components ...
}

credit: redux-saga github

Answer 2

yield can accept Promise.

const {result, components} = yield new Promise(resolve => {
  new Fingerprint2().get(function(result, components) {
    resolve({result, components})
  })
})