About Redis.

• ElastiCache 사용

• EC2에 직접 적용

Amazon Linux (EC2) 에 redis 설치.

# Enable the Extra Packages for Enterprise Linux (EPEL) repository
$ sudo amazon-linux-extras install epel -y
# Install Remi Repository
$ sudo yum install -y https://rpms.remirepo.net/enterprise/remi-release-7.rpm
# Enable the Remi Redis Module
$ sudo yum --enablerepo=remi install redis -y
# Start Redis
$ sudo systemctl start redis
# Enable Redis to start on boot
$ sudo systemctl enable redis
# Check Redis status
$ sudo systemctl status redis

$ redis-server # 혹은 redis-cli 명령어로 로컬호스트에 올라온 레디스에 접속할 수 있다

설치된 redis에 ip bind 풀어주기.

설치된 redis에 비밀번호 걸기.

LoadBalancer 혹은 security 설정.

Step 1: Create a Target Group for Redis

1. Go to the AWS Management Console and navigate to the EC2 Dashboard.

2. Under Load Balancing, select Target Groups and click Create target group.

3. Choose target type: Select Instances.

4. Target group name: Give your target group a name, e.g., redis-target-group.

5. Protocol: Choose TCP.

6. Port: Enter 6379.

7. VPC: Select the VPC where your Redis EC2 instance is running.

8. Health checks: Set the protocol to TCP (Redis doesn’t have HTTP endpoints, so use TCP for health checks).

9. Advanced health check settings: Adjust the health check interval, timeout, and thresholds if needed.

10. Register Targets: Select your Redis EC2 instance and click Add to registered. Then click Create target group.

Step 2: Create a Network Load Balancer (NLB)

1. In the EC2 Dashboard, navigate to Load Balancers and click Create Load Balancer.

2. Choose a load balancer type: Select Network Load Balancer.

3. Name: Give your load balancer a name, e.g., redis-nlb.

4. Scheme: Choose either Internet-facing (if you need external access) or Internal (for VPC-only access).

5. IP address type: Choose IPv4.

6. Listeners:
• By default, a listener on TCP port 80 will be created; change this to TCP and 6379 for Redis.

7. Availability Zones: Select the VPC and the subnets where your Redis instance is running. If you have multiple availability zones, select the corresponding subnets.

8. Click Next.

Step 3: Configure the Load Balancer with the Target Group

1. Select Target Group: In the Target Group section, choose Select a target group and select the Redis target group you created earlier.

2. Click Create Load Balancer.

Step 4: Modify Security Groups

1. Load Balancer Security Group: The NLB itself doesn't need a security group since it operates at the network layer, but you still need to ensure your Redis instance allows inbound traffic from the load balancer.
• In your Redis EC2 instance’s security group, add an inbound rule to allow TCP traffic on port 6379 from the load balancer’s IP range.
• Set the Source to Custom and specify the security group or IP range.

2. Redis Instance Security Group: Allow inbound traffic on port 6379.
• Type: Custom TCP Rule
• Protocol: TCP
• Port Range: 6379
• Source: Choose the security group associated with your load balancer, or set it to 0.0.0.0/0 for public access (this is not recommended for security reasons).

원격으로 redis에 접근하기.

import Redis from 'ioredis'

const redisClient = new Redis({
  host: process.env.REDIS_URL ?? '', // host url
  port: process.env.REDIS_PORT ? +process.env.REDIS_PORT : undefined, // port number
  password: process.env.REDIS_PASSWORD ?? '', // redis password
})

export const redisKeys = {
	// ... 들어갈 key 값에 대한 key factory
} as const

export class RedisClient {
  static async get<T>(key: string) {

    try {
      const value = await redisClient.get(key)
      if (!value) {
        return null
      }
      const parsed = JSON.parse(value) as T
      return parsed
    } catch (e) {
      console.error(e)
      return null
    }
  }

  static async set(key: string, value: string, expire?: number) {
    await redisClient.set(key, value)
    if (expire) {
      await redisClient.expire(key, expire)
    }
  }
}

const redisValue = await RedisClient.get<SerializedType[]>(
	redisKeys.SOME_KEY(params) // key factory 에서 parameter 로 따로 키 값을 구분한다
)

if (redisValue) {
	// 레디스에 값이 저장되어 있다면 그대로 반환
	return rep.status(200).send(redisValue)
}

// ... 비즈니스 로직

const dto = await SomeDTO.getById(req.params.id)
const response = dto.serialize()
await RedisClient.set(
	redisKeys.SOME_KEY(params),
	JSON.stringify(response),
	60 * 60 // expiry time
)

// 레디스에 값이 저장되어 있지 않다면, 위와 같이 set 해주고, 값을 반환
return rep.status(200).send(response)