data.js — react Source File

Source Code

/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 */

import {createContext, useContext} from 'react';

// Note: this file does not demonstrate a real data fetching strategy.
// We only use this to simulate data fetching happening on the server
// while the cache is populated on the client. In a real app, you would
// instead use a data fetching library or Server Components for this.

const DataContext = createContext(null);

export function DataProvider({children, data}) {
  return <DataContext.Provider value={data}>{children}</DataContext.Provider>;
}

// In a real implementation the data would be streamed with the HTML.
// We haven't integrated this part yet, so we'll just use fake data.
const fakeData = [
  "Wait, it doesn't wait for React to load?",
  'How does this even work?',
  'I like marshmallows',
];

export function useData() {
  const ctx = useContext(DataContext);
  if (ctx !== null) {
    // This context is only provided on the server.
    // It is here to simulate a suspending data fetch.
    ctx.read();
  }
  return fakeData;
}