@origins-digital/redis

A NestJS module for Redis integration using ioredis.

Installation

npm install @origins-digital/redis

Features

• Seamless Redis integration with NestJS
• Automatic reconnection handling
• Configurable retry strategy
• Global module support
• Environment-based configuration
• Event handling for connection status

Usage

Basic Setup

import { Module } from '@nestjs/common';
import { RedisModule } from '@origins-digital/redis';

@Module({
  imports: [
    RedisModule.registerAsync({
      useFactory: () => ({
        connectionOptions: {
          host: process.env.REDIS_HOST,
          port: parseInt(process.env.REDIS_PORT),
          password: process.env.REDIS_PASSWORD,
        },
        onClientReady: (client) => {
          console.log('Redis client ready');
        },
      }),
    }),
  ],
})
export class AppModule {}

Using Environment Variables

import { Module } from '@nestjs/common';
import { RedisModule, redisRetryStrategy } from '@origins-digital/redis';

@Module({
  imports: [
    RedisModule.registerAsync({
      useFactory: redisRetryStrategy,
    }),
  ],
})
export class AppModule {}

Using Redis in Services

import { Injectable } from '@nestjs/common';
import { Inject } from '@nestjs/common';
import { IO_REDIS_CACHE } from '@origins-digital/redis';
import Redis from 'ioredis';

@Injectable()
export class CacheService {
  constructor(
    @Inject(IO_REDIS_CACHE)
    private readonly redis: Redis,
  ) {}

  async set(key: string, value: string, ttl?: number): Promise<void> {
    if (ttl) {
      await this.redis.setex(key, ttl, value);
    } else {
      await this.redis.set(key, value);
    }
  }

  async get(key: string): Promise<string | null> {
    return this.redis.get(key);
  }

  async del(key: string): Promise<void> {
    await this.redis.del(key);
  }
}

Retry Strategy Configuration

The package includes a built-in retry strategy that:

• Attempts to reconnect up to 10 times
• Implements exponential backoff with a maximum delay of 5 seconds
• Skips retries in local environment
• Handles connection errors appropriately

const retryStrategy = {
  retryStrategy: (retries) => {
    if (retries > maxConnectRetry || process.env.APP_ENV === 'local') {
      return;
    }
    const delay = Math.min(retries * 500, 5000);
    return delay;
  },
};

Event Handling

The Redis client emits various events that you can listen to:

client.on('error', (err) => {
  console.error('Redis error:', err);
});

client.on('connect', () => {
  console.log('Connected to Redis');
});

client.on('disconnect', () => {
  console.log('Disconnected from Redis');
});

Configuration Options

RedisModuleOptions

type RedisModuleOptions = {
  connectionOptions: RedisOptions;
  onClientReady?: (client: Redis) => void;
};

RedisOptions

interface RedisOptions {
  host?: string;
  port?: number;
  password?: string;
  db?: number;
  retryStrategy?: (retries: number) => number | null;
  reconnectOnError?: (err: Error) => boolean;
  // ... other ioredis options
}

Environment Variables

The package expects the following environment variables:

• REDIS_ENDPOINT: Redis server endpoint (e.g., 'redis://localhost:6379')
• REDIS_PORT: Redis server port
• REDIS_PASSWORD: Redis server password (optional)
• APP_ENV: Application environment (e.g., 'local', 'development', 'production')

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.