use-db

React hook for IndexedDB that mimics useState API

Install

npm install use-db

Why

Why this over use-local-storage-state?

• Capacity. IndexedDB can store hundred of megabytes to gigabytes of data. localStorage limit is around 5-10MB.
• Performance. IndexedDB is async and doesn't block the UI. IndexedDB can store objects without serialization which shaves off the time to do JSON.parse() and JSON.stringify() that's needed when working with localStorage.
• Availability. IndexedDB is available both in Web Worker and Service Worker, localStorage is not. You can write data in those places and then access it in the main thread.
• Maintenance. I've been consistently maintaining many open-source libraries including use-local-storage-state with ~500k downloaders per month.

Usage

import useDb from 'use-db'

export default function Todos() {
    const [todos, setTodos] = useDb('todos', {
        defaultValue: ['buy avocado', 'do 50 push-ups']
    })
}

Todo list example

import React, { useState } from 'react'
import useDb from 'use-db'

export default function Todos() {
    const [todos, setTodos] = useDb('todos', {
        defaultValue: ['buy avocado']
    })
    const [query, setQuery] = useState('')

    function onClick() {
        setQuery('')
        setTodos([...todos, query])
    }

    return (
        <>
            <input value={query} onChange={e => setQuery(e.target.value)} />
            <button onClick={onClick}>Create</button>
            {todos.map(todo => (
                <div>{todo}</div>
            ))}
        </>
    )
}

Removing the data from IndexedDB and resetting to the default

The removeItem() method will reset the value to its default and will remove the data from the IndexedDB. It returns to the same state as when the hook was initially created.

import useDb from 'use-db'

export default function Todos() {
    const [todos, setTodos, removeItem] = useDb('todos', {
        defaultValue: ['buy avocado']
    })

    function onClick() {
        removeItem()
    }
}

API

useDb(key: string, options?: StorageStateOptions)

Returns [value, setValue, removeItem] when called. The first two values are the same as useState(). The third value calls IDBObjectStore.delete() and removes the data from the db.

key

Type: string

⚠️ Be careful with name conflicts as it is possible to access a property which is already in IndexedDB that was created from another place in the codebase or in an old version of the application.

options.defaultValue

Type: any

Default: undefined

The default value. You can think of it as the same as useState(defaultValue).

options.optimistic

Type: boolean

Default: true

IndexedDB is async. When optimistic is enabled, calling setState will synchronously/immediately update the state and it will roll back the state if adding the data to the database fails. You can disable by setting optimistic: false.

Related

• use-storage-state — Supports localStorage, sessionStorage, and any other Storage compatible API.
• use-local-storage-state — Similar to this hook but for localStorage.
• use-session-storage-state — Similar to this hook but for sessionStorage.
• local-db-storage — Tiny wrapper around IndexedDB that mimics localStorage API.