svelte-persisted-store

A Svelte store that persists to local storage. Can sync changes across browser tabs.

Installation

``bash
npm install svelte-persisted-store
`

Usage

Define the store:

`javascript
import { persisted } from 'svelte-persisted-store'

// First param preferences is the local storage key.
// Second param is the initial value.
export const preferences = persisted('preferences', {
theme: 'dark',
pane: '50%',
...
})
`

Then, to use it:

`javascript
import { get } from 'svelte/store'
import { preferences } from './stores'

preferences.subscribe(...) // subscribe to changes
preferences.update(...) // update value
preferences.set(...) // set value
preferences.reset() // reset to initial value
get(preferences) // read value
$preferences // read value with automatic subscription
`

Additional options can be specified:

`javascript
import * as devalue from 'devalue'

// third parameter is options
export const preferences = persisted('local-storage-key', 'default-value', {
serializer: devalue, // defaults to JSON
storage: 'session', // 'session' for sessionStorage, defaults to 'local'
syncTabs: true, // choose whether to sync localStorage across tabs, default is true
onWriteError: (error) => {/ handle or rethrow /}, // Defaults to console.error with the error object
onParseError: (raw, error) => {/ handle or rethrow /}, // Defaults to console.error with the error object
beforeRead: (value) => {/ change value after serialization but before setting store to return value/},
beforeWrite: (value) => {/ change value after writing to store, but before writing return value to local storage/},
})
``

License

MIT