react-use-resource

Convert a promise returning function into a suspense compatible resource.

Installation

npm install react-use-resource

yarn add react-use-resource

Usage

Wrap an application into a ResourcesBoundary component. All request results will be cached in there.

import { Suspense } from 'react';
import { ResourcesBoundary } from 'react-use-resource';

export function Application() {
  return (
    <ResourcesBoundary>
      <Suspense fallback="Loading...">
        <User />
      </Suspense>
    </ResourcesBoundary>
  );
}

Declare a promise returning function in any convenient way.

interface IUser {
  username: string;
}

export function getUser(id: number) {
  return fetch(`.../users/${id}`).then(response => response.json<IUser>());
}

The useResource hook takes a resource id, a promise returning function and a dependency list (which works simmilar to useEffect hook) and returns a resource for a provided function. Returned resource has read and refresh methods.

import { useResource } from 'react-use-resource';

export function User() {
  const resource = useResource('USER', getUser, [42]);

  return (
    <h1>{ resource.read().username }<h1>
  );
};

Resource id should be unique for a rendered component tree. Variables from a dependency list are passed down to a function as an arguments. Cached resource is invalidated upon a component unmount.

Request cancellation

Ideally, upon a dependency list change we want to cancel a previous outgoing request. In order to achieve this our function should return not a simple promise but a tuple of a promise and a cancellation function.

export function getUser(id: number): [Promise<IUser>, () => void] {
  const controller = new AbortController();
  const signal = controller.signal;

  const promise = fetch(`.../users/${id}`, { signal }).then(response => response.json<IUser>());

  return [promise, controller.abort];
}

Lazy resources

Instead of useResource we can use useLazyResource hook. This way the resource will be requested only upon the read or refresh call.

SSR

We can pass a cache property to ResourcesBoundary. All data will be written to and read from this record.

const cache: Record<string, any> = {};

<ResourcesBoundary cache={cache}>
  <Application />
</ResourcesBoundary>