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var saferWebStorage = require("safer-web-storage")

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safer-web-storage v1.1.0

Handle all exception when storage is not available due to user's browser settings. Swap to in-memory storage if sessionStorage is not available.


Browsers that support localStorage and sessionStorage will have a property on the window object named respectively. However, for various reasons, just asserting that property exists may throw exceptions. If it does exist, that is still no guarantee that localStorage is actually available, as various browsers offer settings that disable storages. So a browser may support localStorage, but not make it available to the scripts on the page. One example of that is Safari, which in Private Browsing mode gives us an empty localStorage object with a quota of zero, effectively making it unusable.

Installation and Usage

npm install safer-web-storage
import * as SafeStorage from 'safer-web-storage'

const safeLocalStorage = SafeStorage.createSafeLocalStorage()
const safeSessionStorage = SafeStorage.createSafeSessionStorage()

safeSessionStorage.seItem('pineapples', 20)

If either window.sessionStorage or its methods are not accessible, it swaps to in-memory storage.

This wrapper supports all methods and properties of Web Storage API:

  • getItem
  • setItem
  • removeItem
  • key
  • clear
  • length


createSafeLocalStorage(options) => Storage

createSafeSessionStorage(options) => Storage

You can pass the following properties to options:

errorMessageStringLooks like you've disabled <StorageType>. Enable it to avoid this warning.Error message printed to the browser console when storage is not available

Storage public API

isNativeStorageUsedgetterReturns Boolean
isInMemoryStorageUsedgetterReturns Boolean


To test the library in a browser run:

npm install
npm start


npm ci
npm test
npm run build
npm version [patch|minor|major]
npm publish
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