redis-dataloader

library1.0.2jsnpmunverified

Redis Dataloader wraps Facebook's DataLoader to add Redis as a distributed caching layer, enabling sharing of cache across processes/servers. Current stable version 1.0.2 (last released Nov 2019, low maintenance). Requires both Redis client (node_redis or ioredis) and DataLoader itself. Key differentiator from standard DataLoader: cross-process caching via Redis, TTL support, and async clear/prime methods. Designed for GraphQL backends needing horizontal scalability.

database devops

npm install redis-dataloader

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · REDIS-DATALOADER

redis-dataloader

databasejavascriptv1.0.2

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.

RedisDataLoader

✓ import RedisDataLoader from 'redis-dataloader'

✗ const RedisDataLoader = require('redis-dataloader')

Package exports a factory function; ESM import is default import. CommonJS require works too.

redis

✓ import redis from 'redis'; const client = redis.createClient()

✗ import { RedisClient } from 'redis'

The redis package exports a function, not a class. Use default import.

DataLoader

✓ import DataLoader from 'dataloader'

✗ import { DataLoader } from 'dataloader'

DataLoader uses a default export.

Complete setup: create Redis client, factory-import RedisDataLoader, create base DataLoader, then RedisDataLoader instance with prefix, batch loader, and options including TTL (expire). Demonstrates load, clear (async), and local-only clear operations.

import { createClient } from 'redis'; import DataLoader from 'dataloader'; import RedisDataLoader from 'redis-dataloader'; // Initialize Redis client (only one needed, use node_redis or ioredis) const redisClient = createClient({ url: process.env.REDIS_URL ?? 'redis://localhost:6379' }); await redisClient.connect(); // Factory function: pass redis client const RedisDataLoaderFactory = RedisDataLoader({ redis: redisClient }); // Batch function (simulate DB fetch) const batchFn = async (keys) => keys.map(k => ({ id: k, name: `Item ${k}` })); // Create a standard DataLoader with cache disabled const baseLoader = new DataLoader(batchFn, { cache: false }); // Create RedisDataLoader with prefix 'myapp', base loader, and options const loader = new RedisDataLoaderFactory('myapp', baseLoader, { cache: true, expire: 3600 }); // Load a value (first fetches from Redis, then from batchFn, caches both locally and in Redis) const result = await loader.load(5); console.log(result); // { id: 5, name: 'Item 5' } // Clear a specific key from local and Redis cache await loader.clear(5); // Clear only local cache (not Redis) loader.clearLocal(5); // Clear all local cache loader.clearAllLocal(); await redisClient.disconnect();

Debug

Known issues

breakingclear() returns a Promise (unlike Facebook DataLoader's synchronous clear).

fix

Always await the result of clear(): await loader.clear(key);

affects: >=0.0.0

breakingclearAll() is not available. Redis does not support efficient key-scanning for prefix-based delete.

fix

Use a Redis SCAN or FLUSHDB manually, or implement custom batch clear.

affects: >=0.0.0

breakingprime() always overwrites cache (unlike DataLoader which skips if key exists). Returns a Promise.

fix

Use prime() only when you intend to force-update the cache; otherwise avoid.

affects: >=0.0.0

gotchaRedis-stored values must be JSON or null. Non-serializable types (e.g., Date) need custom serialize/deserialize options.

fix

Provide serialize/deserialize in options to handle Date or other types.

affects: >=0.0.0

gotchaMust disable cache on the inner DataLoader (pass { cache: false }) to avoid double caching conflicts.

fix

Always pass { cache: false } to the base DataLoader.

affects: >=0.0.0

Errors

Common errors & fixes

RedisDataLoader is not a constructor

Calling require('redis-dataloader') directly without invoking the factory function with a redis client.

fix

Use const RedisDataLoader = require('redis-dataloader')({ redis: redisClient });

ERR Error: clearAll is not a function

The RedisDataLoader instance does not have clearAll method.

fix

Clear all keys with a Redis scan + del, or use clearAllLocal() for local cache only.

TypeError: loader.load is not a function

Factory function not invoked properly, resulting in undefined or wrong object.

fix

Ensure RedisDataLoader is called with { redis: client }, then construct new loader with prefix, baseLoader, options.

Upgrade

Version history

1.0.2latest on npm

Audit

Dependencies

dataloaderrequiredCore batching/caching logic from Facebook's DataLoader

redisrequiredRedis client for caching; can use ioredis instead

Agent activity

10 hits · last 30 days

node