Registry / storage / async-cache-dedupe

async-cache-dedupe

library3.4.0jsnpmunverified

An asynchronous caching library with built-in deduplication, ensuring each resource is fetched only once concurrently. Version 3.4.0 is the latest stable, actively maintained. It supports memory and Redis storage backends, with optional TTL, stale-while-revalidate, invalidation, and custom serialization via transformers. Differentiators include automatic deduplication of in-flight requests, safe key serialization via safe-stable-stringify, and seamless integration with GraphQL and other async contexts.

storage

npm install async-cache-dedupe

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INSTALL

IMPORT

SIG · ASYNC-CACHE-DEDUPE

async-cache-dedupe

storagejavascriptv3.4.0

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.

createCache

✓ import { createCache } from 'async-cache-dedupe'

✗ const createCache = require('async-cache-dedupe')

Package provides named ESM export; CommonJS users must use `const { createCache } = require('async-cache-dedupe')`.

createCache (CJS)

✓ const { createCache } = require('async-cache-dedupe')

✗ const createCache = require('async-cache-dedupe')

CommonJS destructure is required; package does not export via module.exports directly.

Cache type

✓ import type { Cache } from 'async-cache-dedupe'

TypeScript users can import the Cache type for type annotations.

Creates a memory cache with 5 second TTL and stale window, defines an async function, and calls it with deduplication.

import { createCache } from 'async-cache-dedupe'; const cache = createCache({ ttl: 5, stale: 5, storage: { type: 'memory' } }); cache.define('fetchSomething', async (key: number) => { console.log('query', key); return { key }; }); const result = await cache.fetchSomething(42); console.log(result); // { key: 42 }

Debug

Known issues

breakingVersion 3.0.0 removed the default export; now only named exports are provided.

fix

Replace `import createCache from 'async-cache-dedupe'` with `import { createCache } from 'async-cache-dedupe'`. For CommonJS, use `const { createCache } = require('async-cache-dedupe')`.

affects: >=3.0.0

breakingIn version 3.0.0, the `opts` parameter for `cache.define` now accepts `ttl`, `stale`, and other options; these were previously part of the createCache config only.

fix

Move per-function TTL/stale options to the `define` call: `cache.define('fn', { ttl: 10 }, async (...args) => {...})`.

affects: >=3.0.0

deprecatedThe `onDedupe`, `onError`, `onHit`, `onMiss` callbacks are deprecated in favor of using `pino` logger integration.

fix

Use the `log` option in storage configuration with a pino-compatible logger instance.

affects: >=3.0.0

breakingVersion 2.x required a different storage format; the `storage` option now expects an object with `type` and `options`.

fix

Update storage config from `{ type: 'redis', client: ... }` to `{ type: 'redis', options: { client: ..., invalidation: ... } }`.

affects: >=3.0.0

gotchaThe cache key is computed using `safe-stable-stringify` on arguments. Mutating arguments after a call will not affect the key but may lead to stale data if the argument object content changes.

fix

Ensure arguments passed to cached functions are immutable or use primitive types for keys.

affects: all

gotchaWhen using Redis storage, the `client` option must be an `ioredis` client; other Redis clients may not work correctly.

fix

Install `ioredis` and create a client with `new Redis()`.

affects: all

deprecatedThe `size` option for memory storage was removed in v3. Use `max` instead.

fix

Replace `storage.options.size` with `storage.options.max`.

affects: >=3.0.0

Errors

Common errors & fixes

TypeError: createCache is not a function

Importing default export instead of named export in ESM or CommonJS.

fix

Use `import { createCache } from 'async-cache-dedupe'` or `const { createCache } = require('async-cache-dedupe')`.

Error: storage.type must be memory or redis

Providing storage option with an incorrect type or format.

fix

Set storage object as `{ type: 'memory' }` or `{ type: 'redis', options: { client: ... } }`.

Error: Redis client is required for redis storage

Missing `client` option in redis storage config.

fix

Add a valid ioredis client: `{ type: 'redis', options: { client: new (require('ioredis'))() } }`.

TypeError: cache.define is not a function

Calling `define` on the cache before it is fully created or using an incorrect reference.

fix

Ensure `createCache` returns an object and you call `define` on it: `const cache = createCache(...); cache.define(...)`.

Error: Invalid transformer: must have serialize and deserialize methods

Providing a transformer object missing required methods.

fix

Ensure transformer has both `serialize` and `deserialize` functions.

Upgrade

Version history

3.4.0latest on npm

Audit

Dependencies

safe-stable-stringifyrequiredUsed for deterministic cache key generation from arguments.

pinooptionalOptional logger interface for cache events (hit, miss, error).

Agent activity

46 hits · last 30 days

node

Resources

githubhttps://github.com/mcollina/async-cache-dedupe ↗

packageasync-cache-dedupe ↗

homepagehttps://github.com/mcollina/async-cache-dedupe#readme ↗