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@kentcdodds
Created April 3, 2020 23:32
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function useAbortController() {
const abortControllerRef = React.useRef()
const getAbortController = React.useCallback(() => {
if (!abortControllerRef.current) {
abortControllerRef.current = new AbortController()
}
return abortControllerRef.current
}, [])
React.useEffect(() => {
return () => getAbortController().abort()
}, [getAbortController])
const getSignal = React.useCallback(() => getAbortController().signal, [
getAbortController,
])
return getSignal
}
@rejhgadellaa
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rejhgadellaa commented Jul 25, 2024

Inspired by @charlestbell

  • Leave control to the user of the hook to abort() anytime they want, not just on unmount.
  • Returns a (memoized) object that resembles the AbortController API: { abort, signal } instead of the getSignal function.
  • Strict null checks on abortCtrlRef.current instead of falsey for perf (just because).
function useAbortController() {

  const abortCtrlRef = useRef( null );

  const getAbortController = useCallback(
    () => {
      if ( abortCtrlRef.current === null ) abortCtrlRef.current = new AbortController();
      return abortCtrlRef.current;
    },
    []
  );

  const abort = useCallback(
    () => {
      if ( abortCtrlRef.current !== null ) {
        abortCtrlRef.current.abort();
        abortCtrlRef.current = null;
      }
    },
    []
  );

  return useMemo(
    () => ({
      get signal() { return getAbortController().signal; },
      abort,
    }),
    [ getAbortController, abort ]
  );

}

Usage:

function MyComponent( props ) {

  // { abort, signal } just like a real AbortController
  const { abort, signal } = useAbortController();

  // Some useEffect or other thing you need to be able to abort
  useEffect(() => fetch( url, { signal } ), [ signal ]);

  // The user of the hook can abort whenever they please.
  useEffect(() => () => abort(), [ abort ]);

}

@aovchinn
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aovchinn commented Mar 20, 2025

@rejhgadellaa that code has get signal() { return getAbortController().signal; } and then
const { abort, signal } = useAbortController();

I think it will call getter right away, why not just

const useAbortController = () => {
    const controllerRef = useRef<AbortController | null>(null);
    if (controllerRef.current === null) {
        controllerRef.current = new AbortController();
    }

    return {
        abort: controllerRef.current.abort,
        signal: controllerRef.current.signal,
    };
};

in versions above controller is created only when fetch is issued,
for example if there is some button that issues a request, we do not need abortController until it is pressed

@rejhgadellaa
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Hmm good point, I may have overdone it with the get signal() { ... } haha

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