Hooked on Storage

A React hook to provide efficient access to properties in storage. It is compatible with the following storage adapters:

• localStorage
• sessionStorage
• @react-native-community/async-storage

Install

This package can be installed from NPM.

$ yarn add hooked-on-storage

Usage

1. Create a stored property with createStorage

First, you'll need to declare a stored property:

import { createStorage } from "hooked-on-storage";

const counter = createStorage<number>({
  key: "count",
  adapter: localStorage,
  defaultValue: 0,
});

The counter provides some conveniences over using localStorage directly. Keep in mind that if you directly modify a value in localStorage or your components won't rerender.

Set the value

The value will automatically be serialized using JSON.stringify before being inserted into storage. You can customize this behavior by specifing the parse option.

await counter.set(1);

Get the current value

The value will automatically be deserialized using JSON.parse. You can customize this behavior by specifing the parse option.

If the value does not exist in storage, the defaultValue will be returned.

await counter.get();

Remove the value

await counter.remove();

Subscribe to changes

counter.onChange((value) => {
  console.log("changed:", value);
});

2: Setup the <StorageProvider />

At the top of your component tree, you'll need to define a provider for your storage.

import { StorageProvider, Hydrated } from "hooked-on-storage";

ReactDOM.render(
  <StorageProvider hydrate={[counter]}>
    <h1>Counter</h1>

    <Hydrated fallback={<p>Hydrating...</p>}>
      <Counter />
    </Hydrated>
  </StorageProvider>
);

Using the <Hydrated /> component is entirely optional. It allows us to render a loading screen while we load the values from storage.

Step 3: Use a stored property with useStorage

import { useStorage } from "hooked-on-storage";

const Counter = () => {
  const [count, setCount, hydrated] = useStorage(counter);
  const decrement = () => setCount(count - 1);
  const increment = () => setCount(count + 1);

  // Because we used `<Hydrated />` above, this will never be false.
  if (!hydrated) {
    return <p>Hydrating...</p>;
  }

  return (
    <div>
      <h4>{count}</h4>
      <button onClick={increment}>-</button>
      <button onClick={decrement}>+</button>
    </div>
  );
};