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

9 hits · last 30 days

node

Resources

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

packagelayered-cache ↗

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