idb-keyval
Version:
A super-simple-small keyval store built on top of IndexedDB
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# IDB-Keyval
[](https://www.npmjs.com/package/idb-keyval)
[](http://img.badgesize.io/https://cdn.jsdelivr.net/npm/idb-keyval/dist/idb-keyval-iife.min.js)
This is a super-simple-small promise-based keyval store implemented with IndexedDB, largely based on [async-storage by Mozilla](https://github.com/mozilla-b2g/gaia/blob/master/shared/js/async_storage.js).
[localForage](https://github.com/localForage/localForage) offers similar functionality, but supports older browsers with broken/absent IDB implementations. Because of that, it's 7.4k, whereas idb-keyval is < 600 bytes. Also, it's tree-shaking friendly, so you'll probably end up using fewer than 500 bytes. Pick whichever works best for you!
This is only a keyval store. If you need to do more complex things like iteration & indexing, check out [IDB on NPM](https://www.npmjs.com/package/idb) (a little heavier at 1.7k). The first example in its README is how to recreate this library.
## Usage
### set:
```js
import { set } from 'idb-keyval';
set('hello', 'world');
set('foo', 'bar');
```
Since this is IDB-backed, you can store anything structured-clonable (numbers, arrays, objects, dates, blobs etc).
All methods return promises:
```js
import { set } from 'idb-keyval';
set('hello', 'world')
.then(() => console.log('It worked!'))
.catch(err => console.log('It failed!', err));
```
### get:
```js
import { get } from 'idb-keyval';
// logs: "world"
get('hello').then(val => console.log(val));
```
If there is no 'hello' key, then `val` will be `undefined`.
### keys:
```js
import { keys } from 'idb-keyval';
// logs: ["hello", "foo"]
keys().then(keys => console.log(keys));
```
### del:
```js
import { del } from 'idb-keyval';
del('hello');
```
### clear:
```js
import { clear } from 'idb-keyval';
clear();
```
### Custom stores:
By default, the methods above use an IndexedDB database named `keyval-store` and an object store named `keyval`. You can create your own store, and pass it as an additional parameter to any of the above methods:
```js
import { Store, set } from 'idb-keyval';
const customStore = new Store('custom-db-name', 'custom-store-name');
set('foo', 'bar', customStore);
```
That's it!
## Installing
### Via npm + webpack/rollup
```sh
npm install idb-keyval
```
Now you can require/import `idb-keyval`:
```js
import { get, set } from 'idb-keyval';
```
If you're targeting older versions of IE, you may have more luck with:
```js
const idb = require('idb-keyval/dist/idb-keyval-cjs-compat.min.js');
```
### Via `<script>`
* `dist/idb-keyval.mjs` is a valid JS module.
* `dist/idb-keyval-iife.js` can be used in browsers that don't support modules. `idbKeyval` is created as a global.
* `dist/idb-keyval-iife.min.js` As above, but minified.
* `dist/idb-keyval-iife-compat.min.js` As above, but works in older browsers such as IE 10.
* `dist/idb-keyval-amd.js` is an AMD module.
* `dist/idb-keyval-amd.min.js` As above, but minified.
These built versions are also available on jsDelivr, e.g.:
```html
<script src="https://cdn.jsdelivr.net/npm/idb-keyval@3/dist/idb-keyval-iife.min.js"></script>
<!-- Or in modern browsers: -->
<script type="module">
import { get, set } from 'https://cdn.jsdelivr.net/npm/idb-keyval@3/dist/idb-keyval.mjs';
</script>
```
## Updating from 2.x
2.x exported an object with methods:
```js
// This no longer works in 3.x
import idbKeyval from 'idb-keyval';
idbKeyval.set('foo', 'bar');
```
Whereas in 3.x you import the methods directly:
```js
import { set } from 'idb-keyval';
set('foo', 'bar');
```
This is better for minification, and allows tree shaking.