layered-cache

library4.0.2jsnpmunverified

A hierarchical cache manager for Node.js that chains multiple cache layers (e.g., in-memory LRU, database, remote server) with automatic fallback and propagation. v4.0.2 is the current stable release, with infrequent updates. Key differentiator: supports arbitrary key types, optional multi-get/set, and a customizable not-found check. The library is ESM-only and requires Node >=10.

database

npm install layered-cache

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · LAYERED-CACHE

layered-cache

databasejavascriptv4.0.2

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.

LCache

✓ import LCache from 'layered-cache'

✗ const LCache = require('layered-cache')

ESM-only; CommonJS require will fail.

InterfaceLayer (type)

✓ import type { InterfaceLayer } from 'layered-cache'

✗ import { InterfaceLayer } from 'layered-cache'

InterfaceLayer is a TypeScript interface, not a runtime value. Use type import.

Layer (type)

✓ import type { Layer } from 'layered-cache'

✗ import { Layer } from 'layered-cache'

Layer is a TypeScript type alias for the simple object layer definition.

Demonstrates creating a three-layered cache with in-memory LRU, async DB layer, and remote fallback.

import LRU from 'lru-cache' import LCache from 'layered-cache' const lru = new LRU({ max: 100 }) const cache = new LCache([ lru, { get: async (key) => { // simulate DB query return null }, set: async (key, value) => { // save to DB } }, { get: async (key) => `remote-${key}` } ]) const value = await cache.get('foo') console.log(value) // 'remote-foo' // After first get, LRU and DB layer have the value. const cached = await cache.get('foo') console.log(cached) // 'remote-foo' (from LRU)

Debug

Known issues

breakingThe library is ESM-only since v4.0.0. CommonJS require() will throw an error.

fix

Migrate to ESM by using import statements or dynamic import().

affects: >=4.0.0

gotchaValues equal to undefined or null are treated as 'not found' by default. This can cause unexpected cache misses.

fix

Provide a custom isNotFound option to override the default behavior.

affects: all

gotchaThe interfaces 'InterfaceLayer' and 'Layer' are TypeScript-only; they are not runtime values. Attempting to import them as values will produce undefined.

fix

Use `import type { InterfaceLayer } from 'layered-cache'`.

affects: >=4.0.0

Errors

Common errors & fixes

ERR_REQUIRE_ESM

Using require() with ESM-only package layered-cache v4+.

fix

Replace require() with import or use dynamic import().

TypeError: LCache is not a constructor

Importing the default export incorrectly, e.g., named import { LCache }.

fix

Use `import LCache from 'layered-cache'`.

Error: A layer must have at least one of methods: 'get' or 'mget'

Providing a layer that implements neither get nor mget.

fix

Ensure every layer implements get() or mget().

Upgrade

Version history

4.0.2latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

13 hits · last 30 days

node

Resources

githubgit://github.com/kaelzhang/node-layered-cache ↗

packagelayered-cache ↗

homepagehttps://github.com/kaelzhang/node-layered-cache#readme ↗