fetchye-core/es/useSubscription.js

Core components of the Fetchye library

/*
 * Copyright 2020 American Express Travel Related Services Company, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */
import { useRef } from 'react';

const useSubscription = () => {
  const subscribers = useRef(new Set());
  return [function notify() {
    subscribers.current.forEach(callback => {
      callback();
    });
  }, function subscribe(callback) {
    subscribers.current.add(callback);
    return () => {
      subscribers.current.delete(callback);
    };
  }];
};

export default useSubscription;