Registry / database / mharj-mongoose-cache

mharj-mongoose-cache

library0.9.3jsnpmunverified

An in-memory cache layer for Mongoose models that reduces database queries by maintaining a local copy of documents. Version 0.9.3, actively developed. Supports importing cached data from Mongoose queries, retrieving documents by ID or with list operations, and populating arrays of IDs. Can be synchronized via change streams, model hooks, or explicit add/delete calls. Emits events for cache updates, suitable for pushing data to presentation layers like websockets. Requires Mongoose >= 6.0.0 and @avanio/logger-like >= 0.0.1 as peer dependencies. Compared to mongoose-lean-cache or query-level caching, this provides a model-level cache with a simple API and change stream integration.

database

npm install mharj-mongoose-cache

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · MHARJ-MONGOOSE-CAC

mharj-mongoose-cache

databasejavascriptv0.9.3

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.

ModelCache

✓ import { ModelCache } from 'mharj-mongoose-cache'

✗ const ModelCache = require('mharj-mongoose-cache')

The package is ESM-only and ships TypeScript types. CommonJS require() will not work.

ModelCache

✓ import { ModelCache } from 'mharj-mongoose-cache'

✗ import ModelCache from 'mharj-mongoose-cache'

ModelCache is a named export, not a default export.

Creates a ModelCache for a 'Car' model, imports all documents, and demonstrates basic operations: get by ID, list all, iterate in chunks, and listen for updates.

import { ModelCache } from 'mharj-mongoose-cache'; import mongoose from 'mongoose'; // Define your Mongoose schema and model interface ICar { _id: string; name: string; } const carSchema = new mongoose.Schema<ICar>({ name: String }); const CarModel = mongoose.model<ICar>('Car', carSchema); // Create cache instance with logger const CarCache = new ModelCache<ICar>('Car', { logger: console }); // Import initial data from database const cars = await CarModel.find(); CarCache.import(cars); // Retrieve a document by ID declare const carId: string; const car = CarCache.get(carId); // List all documents const allCars = CarCache.list(); // Use iterator to process in chunks const chunkSession = CarCache.getChunkSession(100, { sort: (a, b) => a.name.localeCompare(b.name) }); const iter = chunkSession.getIterator(); for (const chunk of iter) { console.log(`Processing chunk of ${chunk.chunk.length} cars`); } // Listen for cache updates CarCache.on('updated', () => { console.log('Car cache updated'); });

Debug

Known issues

gotchaThe cache is in-memory and not persisted. Restarting the application will lose the cache until re-imported.

fix

Re-import data from the database on application startup using the import() method.

affects: >=0.0.0

gotchaModelCache instances are not automatically synchronized with database changes unless you manually set up change streams or hooks.

fix

Wire up Mongoose change streams or use post-save/post-remove hooks to call cache.add() and cache.delete() accordingly.

affects: >=0.0.0

gotchaThe getChunkSession method with a sort function requires stable sort, as sort is done by Array.prototype.sort which is stable in Node.js >= 12 but may behave differently in older engines.

fix

Ensure your Node.js version supports stable sort (v12+), or implement a custom sort with stable characteristics.

affects: >=0.0.0

gotchaThe cache does not handle Mongoose Document methods. Cached objects are plain JavaScript objects, not full Mongoose documents.

fix

Use Mongoose hydrate if you need a full document: CarModel.hydrate(cachedObj)

affects: >=0.0.0

Errors

Common errors & fixes

Cannot find module 'mharj-mongoose-cache'

Package not installed, or installed as dev dependency instead of production dependency.

fix

Run 'npm install mharj-mongoose-cache' --save

Uncaught TypeError: ModelCache is not a constructor

Using default import instead of named import.

fix

Use import { ModelCache } from 'mharj-mongoose-cache'

Upgrade

Version history

0.9.3latest on npm

Audit

Dependencies

mongooserequiredPeer dependency: Mongoose >= 6.0.0 is required for the cache to work with Mongoose models and change streams.

@avanio/logger-likeoptionalPeer dependency: Logger interface for logging cache operations.

Agent activity

7 hits · last 30 days

node

Resources

githubhttps://github.com/mharj/mongoose-cache ↗

packagemharj-mongoose-cache ↗

homepagehttps://github.com/mharj/mongoose-cache#readme ↗