Registry / storage / simple-memory-storage

simple-memory-storage

library1.0.0jsnpmunverified

A lightweight, zero-dependency in-memory storage implementation that mirrors the Web Storage API (localStorage/sessionStorage). Version 1.0.0 is the initial stable release, with no further updates since. It provides a simple JavaScript object-based store with methods: setItem, getItem, removeItem, clear, key, and length. Differentiates from localStorage by not persisting data, making it ideal for testing and ephemeral state in Node.js or browser environments. Includes TypeScript types.

storage

npm install simple-memory-storage

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · SIMPLE-MEMORY-STOR

simple-memory-storage

storagejavascriptv1.0.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

SimpleMemoryStorage

✓ import { SimpleMemoryStorage } from 'simple-memory-storage'

✗ import SimpleMemoryStorage from 'simple-memory-storage'

Only named export available; default import will cause runtime error.

SimpleMemoryStorage

✓ import { SimpleMemoryStorage } from 'simple-memory-storage'

✗ const { SimpleMemoryStorage } = require('simple-memory-storage')

Package is ESM-only; CommonJS require is not supported.

SimpleMemoryStorage

✓ const { SimpleMemoryStorage } = await import('simple-memory-storage')

✗ const SimpleMemoryStorage = require('simple-memory-storage')

Dynamic import works in ESM; require will throw MODULE_NOT_FOUND.

Instantiate SimpleMemoryStorage and use Web Storage API methods (setItem, getItem, removeItem, clear, key, length).

import { SimpleMemoryStorage } from 'simple-memory-storage'; const storage = new SimpleMemoryStorage(); storage.setItem('key1', 'value1'); console.log(storage.length); // 1 console.log(storage.key(0)); // 'key1' console.log(storage.getItem('key1')); // 'value1' storage.setItem('key2', 'value2'); console.log(storage.length); // 2 console.log(storage.getItem('key2')); // 'value2' storage.removeItem('key2'); console.log(storage.getItem('key2')); // null storage.clear(); console.log(storage.length); // 0

Debug

Known issues

gotchaStorage is not shared between instances; each SimpleMemoryStorage has its own independent data.

fix

Create a single instance and pass it around, or use a global singleton pattern.

affects: >=1.0.0

gotchaThe length property is a number that only updates after mutations; it is not reactive.

fix

Always read length after calling setItem/removeItem/clear to get the current count.

affects: >=1.0.0

gotchakey() returns null if index is out of bounds; does not throw an error.

fix

Check if the returned value is null before using it as a key.

affects: >=1.0.0

gotchaThe storage only stores string values; other types are coerced to strings.

fix

Use JSON.stringify/parse for non-string data.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: simple_memory_storage_1.SimpleMemoryStorage is not a constructor

Using default import instead of named import.

fix

Change to `import { SimpleMemoryStorage } from 'simple-memory-storage'`.

Cannot find module 'simple-memory-storage'

Attempting to use CommonJS require on an ESM-only package.

fix

Switch to ESM imports (`import { SimpleMemoryStorage } from 'simple-memory-storage'`) or use dynamic import in CommonJS.

TypeError: storage.key is not a function

Using a numeric index directly on the storage object instead of the key() method.

fix

Use `storage.key(index)` instead of `storage[index]`.

Upgrade

Version history

1.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

33 hits · last 30 days

node

Resources

githubhttps://github.com/bouzuya/simple-memory-storage ↗

packagesimple-memory-storage ↗

homepagehttps://github.com/bouzuya/simple-memory-storage#readme ↗