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@gragland
Last active November 30, 2022 18:21
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What would you like to do?
React Hook recipe from https://usehooks.com
import React, { useState, useEffect, useCallback } from 'react';
// Usage
function App() {
const { execute, status, value, error } = useAsync(myFunction, false);
return (
<div>
{status === 'idle' && <div>Start your journey by clicking a button</div>}
{status === 'success' && <div>{value}</div>}
{status === 'error' && <div>{error}</div>}
<button onClick={execute} disabled={status === 'pending'}>
{status !== 'pending' ? 'Click me' : 'Loading...'}
</button>
</div>
);
}
// An async function for testing our hook.
// Will be successful 50% of the time.
const myFunction = () => {
return new Promise((resolve, reject) => {
setTimeout(() => {
const rnd = Math.random() * 10;
rnd <= 5
? resolve('Submitted successfully 🙌')
: reject('Oh no there was an error 😞');
}, 2000);
});
};
// Hook
const useAsync = (asyncFunction, immediate = true) => {
const [status, setStatus] = useState('idle');
const [value, setValue] = useState(null);
const [error, setError] = useState(null);
// The execute function wraps asyncFunction and
// handles setting state for pending, value, and error.
// useCallback ensures the below useEffect is not called
// on every render, but only if asyncFunction changes.
const execute = useCallback(() => {
setStatus('pending');
setValue(null);
setError(null);
return asyncFunction()
.then(response => {
setValue(response);
setStatus('success');
})
.catch(error => {
setError(error);
setStatus('error');
});
}, [asyncFunction]);
// Call execute if we want to fire it right away.
// Otherwise execute can be called later, such as
// in an onClick handler.
useEffect(() => {
if (immediate) {
execute();
}
}, [execute, immediate]);
return { execute, status, value, error };
};
@devgioele
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devgioele commented Mar 17, 2022

Thanks for the quick reply @xandris! The actual problem was that not passing a reference stable function to useAsync caused infinite calls. To avoid that this function is recreated on each render, my solution is to wrap this function first with useCallback and then passing it to useAsync.

The fact that execute was called 3 times... that was because I was actually using it in 3 different places, but didn't realize it!

@TusharShahi
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Is it ideal to use a function as a useCallback dependency? Function is created fresh in every render (unless handled).

@tamiradler
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The init value of state should be depend on immediate variable:
const [status, setStatus] = useState(() => immediate ? 'pending' : 'idle' );

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