[Redis 시리즈 1편] Spring Boot 에 Redis 라이브러리인 Lettuce 적용

코드는 https://github.com/bkjeon1614/java-example-code/tree/develop/bkjeon-mybatis-codebase 참고 부탁드립니다.

Lettuce

Lettuce 란 Netty(비동기 이벤트 기반 고성능 네트워크 프레임워크) 기반이며 고성능, 확장가능, 스레드세이프등을 지원한다.

Lettuce 를 선택한 이유

주로 java 쪽에서는 Lettuce 말고도 Jedis 도 많이 사용한다고 한다. 그러나 Jedis 에 비해 몇 배 이상의 성능, 빠른 피드백, 심플하게 디자인된 코드, 잘 기재된 공식문서 등의 이유로 Lettuce 를 많이 사용하고 있는 추세라고 한다.

환경

Redis 설치 (with. Docker)

$ sudo docker run --name redis-primary -d -p 6379:6379 redis

// 해당 컨테이너에 접속
$ docker exec -it redis-primary /bin/bash

// 모니터링
$ redis-cli -h localhost -p 6379 monitor | grep foo

적용

의존성 추가 (Lettuce 는 spring-data-redis 만 추가하면 기본의존성으로 사용이 가능)

implementation('org.springframework.boot:spring-boot-starter-data-redis')

RedisConnectionFactory 인터페이스를 통해 LettuceConnectionFactory를 생성하여 반환하는 코드를 작성한다.

[RedisConfig.java]

package com.example.bkjeon.base.config.redis;

import java.time.Duration;

import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.RedisStaticMasterReplicaConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceClientConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.repository.configuration.EnableRedisRepositories;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
import org.springframework.data.redis.serializer.StringRedisSerializer;

import io.lettuce.core.ReadFrom;
import lombok.RequiredArgsConstructor;

@Configuration
@EnableRedisRepositories
@RequiredArgsConstructor
public class RedisConfig {

	private final RedisProperties redisProperties;

	@Bean
	public RedisTemplate<String, Object> redisTemplate() {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory());
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(new StringRedisSerializer());
        return redisTemplate;
	}

	@Bean
	public RedisConnectionFactory redisConnectionFactory() {
        LettuceConnectionFactory connectionFactory;

        LettuceClientConfiguration clientConfig = LettuceClientConfiguration
            .builder()
            .commandTimeout(Duration.ofMillis(500))
            .build();
        RedisStaticMasterReplicaConfiguration staticMasterReplicaConfiguration =
            new RedisStaticMasterReplicaConfiguration(
                redisProperties.getHost(),
                redisProperties.getPort()
            );
            
        connectionFactory = new LettuceConnectionFactory(staticMasterReplicaConfiguration, clientConfig);

        return connectionFactory;
	}

	@Bean
	@Primary
	public RedisCacheManager isLettuceCacheManager() {
        RedisCacheConfiguration redisCacheConfiguration = RedisCacheConfiguration
            .defaultCacheConfig()
            .entryTtl(Duration.ofSeconds(60))
            .serializeKeysWith(
                RedisSerializationContext.SerializationPair.fromSerializer(
                    new StringRedisSerializer()))
            .serializeValuesWith(
                RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer()));

        return RedisCacheManager.RedisCacheManagerBuilder
            .fromConnectionFactory(redisConnectionFactory())
            .cacheDefaults(redisCacheConfiguration)
            .build();
	}

}

yaml 을 작성 (RedisProperties를 통해서 properties에 저장한 host, port를 가지고 와서 연결한다.)

...

spring:
  redis:
    host: localhost
    port: 6379

...

테스트용 컨트롤러 작성
[RedisController.java]

package com.example.bkjeon.base.services.api.v1.cache;

import java.util.List;

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration;
import org.springframework.boot.autoconfigure.data.redis.RedisReactiveAutoConfiguration;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.example.bkjeon.entity.cache.CacheExampleData;

import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
import lombok.RequiredArgsConstructor;

@RestController
@RequiredArgsConstructor
@RequestMapping("v1/redis")
public class RedisController {

    private final CacheService cacheService;

    @ApiOperation("Cache Example Data List")
    @GetMapping("examples/cache")
    public List<CacheExampleData> getRedisExampleList(
        @ApiParam(
            value = "bkjeon: bkjeon관련 데이터, example:example 관련 데이터",
            name = "exampleType",
            required = true
        ) @RequestParam String exampleType
    ) {
        return cacheService.getRedisExampleList(exampleType);
    }

}

테스트용 서비스 작성
[CacheService.java]

...

@Cacheable(value = "foo", key = "#exampleType", cacheManager = "isLettuceCacheManager")
public List<CacheExampleData> getRedisExampleList(String exampleType) {
    List<CacheExampleData> exampleList = new ArrayList<>();

    for (int i=1; i<7; i++) {
        CacheExampleData cacheExampleData = CacheExampleData.builder()
            .exampleNo(i)
            .writer(exampleType)
            .build();
        exampleList.add(cacheExampleData);
    }

    return exampleList;
}

...

Entity 클래스 작성

package com.example.bkjeon.entity.cache;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Getter;
import lombok.NoArgsConstructor;

@Builder
@Getter
@NoArgsConstructor
@AllArgsConstructor
public class CacheExampleData {

    private Integer exampleNo;
    private String writer;

}

테스트

$ redis-cli -h localhost -p 6379 monitor | grep foo

java-redis-lettuce-1

참고

https://jojoldu.tistory.com
https://lettuce.io/core/release/reference/