Instruction file imported from Dev-Devarsh/BE-node-microservice-boilerplate (.cursor/rules/redis-and-caching.mdc). Copyright stays with the author.

Redis & Caching Conventions

Redis client lives at src/infrastructure/redis/. Import the singleton cacheService:

import { cacheService } from '../../../infrastructure/redis/index.js';

Cache-Aside pattern (in Services)

async getById(id: string): Promise<IEntity> {
  const cached = await cacheService.get<IEntity>('namespace', id);
  if (cached != null) return cached;

  const entity = await this.repository.findById(id);
  if (entity == null) throw new NotFoundError();

  await cacheService.set('namespace', id, entity, 300); // 5 min TTL
  return entity;
}

Rules

• Every cacheService.set() MUST have an explicit TTL — no infinite caching
• Invalidate on writes: cacheService.invalidate('namespace', id)
• Bulk invalidate: cacheService.invalidatePattern('namespace') clears all namespace:* keys
• Redis is optional — all methods return null/false when Redis is down, code falls through to MongoDB
• Namespace pattern: user:123, user:list:1:20:all, user:analytics:retention:...

TTL guidelines

Token blacklist (in infrastructure/redis/token-blacklist.service.ts)

• blacklistToken(token) — on logout, TTL = remaining token lifetime
• revokeAllUserTokens(userId) — on password change, invalidates ALL tokens via iat check
• isTokenBlacklisted(token) + isTokenRevokedForUser(userId, iat) — checked in auth.middleware.ts