redis clients springboot springboot_dbselect

Redis DB select

Redis Developer Course	Redis Technical Support	Redis Enterprise Server

Spring RedisTemplate

레디스 서버는 기본적으로 16개의 DB(0번 ~ 15번)를 제공합니다. redis-cli에서는 select 명령으로 DB를 이동할 수 있습니다. 그러나 Spring에서 제공하는 RedisTemplate에는 DB를 이동(선택)할 수 있는 select 메소드를 제공하지 않습니다. 그럼 어떻게 여러 DB를 사용할 수 있는지 알아보겠습니다.

• 레디스 서버에서 DB 개수 설정 방법: redis.conf 파일에서 databases로 변경할 수 있습니다. 변경 후에는 레디스 서버를 재시작해야 합니다.
• 레디스 클러스터(cluster)에서는 하나의 DB(0번)만 사용할 수 있습니다.
• Lettuce에서 제공하는 RedisClient에서는 select() 메소드로 DB를 이동(선택)할 수 있습니다. 이것에 대한 설명은 아래에 있습니다.

Project 생성: start.spring.io

Project: Gradle Language: Java Spring Boot 3.1.4 Group: com.redisgate Artifact: dbselect Packaging: Jar Java: 17 Dependencies Spring Web Lombok Spring Data Redis(Access+Driver)

Main Class: DbselectApplication

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @Slf4j public class DbselectApplication { public static void main(String[] args) { SpringApplication.run(DbselectApplication.class, args); log.info("DbselectApplication 시작"); } }

Class RedisConfig

DB를 선택할 수 있도록 dbno를 받도록 했다. redisConnectionFactory(int dbno)
@Bean을 사용하지 않는다.

DB 선택 방법

• redisConfig에서 DB를 설정: redisConfig.setDatabase(dbno);
  
• connectionFactory에서 DB를 선택: connectionFactory.getConnection().select(dbno);
  

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.RedisStandaloneConfiguration; import org.springframework.data.redis.connection.lettuce.LettuceClientConfiguration; import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory; @Configuration @Slf4j public class RedisConfig { @Value("${redis.host}") private String host; @Value("${redis.port}") private int port; @Value("${redis.password}") private String password; @Value("${redis.clientName}") private String clientName; public LettuceConnectionFactory redisConnectionFactory(int dbno) { log.info("host: {}, port: {}, dbno: {}", host, port, dbno); // Redis Config final RedisStandaloneConfiguration redisConfig = new RedisStandaloneConfiguration(host, port); redisConfig.setPassword(password); redisConfig.setDatabase(dbno); // Client Config final LettuceClientConfiguration clientConfig = LettuceClientConfiguration.builder() .clientName(clientName) .build(); LettuceConnectionFactory connectionFactory = new LettuceConnectionFactory(redisConfig, clientConfig); connectionFactory.setShareNativeConnection(true); // connectionFactory.getConnection().select(dbno); return connectionFactory; } }

Class RedisConfigDb0 extends RedisConfig

0번 DB를 선택하는 클래스: redisConnectionFactory(0):

@Bean(name = "stringRedisTemplateDb0") Bean 이름을 지정한다.

setConnectionFactory()로 connectionFactory를 설정한다.

• redisTemplate.setConnectionFactory(redisConnectionFactoryDb0());
  
• stringRedisTemplate.setConnectionFactory(redisConnectionFactoryDb0());
  

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.Primary; import org.springframework.data.redis.connection.RedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.data.redis.serializer.StringRedisSerializer; @Configuration @Slf4j public class RedisConfigDb0 extends RedisConfig { @Bean @Primary public RedisConnectionFactory redisConnectionFactoryDb0() { log.info("redisConnectionFactoryDb0 시작"); return redisConnectionFactory(0); } @Bean @Qualifier("redisTemplateDb0") public RedisTemplate<String, Object> redisTemplateDb0() { RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>(); redisTemplate.setConnectionFactory(redisConnectionFactoryDb0()); redisTemplate.afterPropertiesSet(); return redisTemplate; } @Bean(name = "stringRedisTemplateDb0") public StringRedisTemplate stringRedisTemplateDb0() { final StringRedisTemplate stringRedisTemplate = new StringRedisTemplate(); stringRedisTemplate.setKeySerializer(new StringRedisSerializer()); stringRedisTemplate.setValueSerializer(new StringRedisSerializer()); stringRedisTemplate.setConnectionFactory(redisConnectionFactoryDb0()); return stringRedisTemplate; } }

Class RedisConfigDb1 extends RedisConfig

1번 DB를 선택하는 클래스: redisConnectionFactory(1):

@Bean(name = "stringRedisTemplateDb1") Bean 이름을 지정한다.

setConnectionFactory()로 connectionFactory를 설정한다.

• redisTemplate.setConnectionFactory(redisConnectionFactoryDb1());
  
• stringRedisTemplate.setConnectionFactory(redisConnectionFactoryDb1());
  

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.RedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.data.redis.serializer.StringRedisSerializer; @Configuration @Slf4j public class RedisConfigDb1 extends RedisConfig { @Bean public RedisConnectionFactory redisConnectionFactoryDb1() { log.info("redisConnectionFactoryDb1 시작"); return redisConnectionFactory(1); } @Bean @Qualifier("redisTemplateDb1") public RedisTemplate<String, Object> redisTemplateDb1() { RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>(); redisTemplate.setConnectionFactory(redisConnectionFactoryDb1()); redisTemplate.afterPropertiesSet(); return redisTemplate; } @Bean(name = "stringRedisTemplateDb1") public StringRedisTemplate stringRedisTemplateDb1() { final StringRedisTemplate stringRedisTemplate = new StringRedisTemplate(); stringRedisTemplate.setKeySerializer(new StringRedisSerializer()); stringRedisTemplate.setValueSerializer(new StringRedisSerializer()); stringRedisTemplate.setConnectionFactory(redisConnectionFactoryDb1()); return stringRedisTemplate; } }

Class RedisRepositoryAutowired

@Autowired를 이용한 Repository
Bean으로 지정한 이름을 사용한다.

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.stereotype.Repository; @Repository @Slf4j public class RedisRepositoryAutowired { @Autowired private StringRedisTemplate stringRedisTemplateDb0; @Autowired private StringRedisTemplate stringRedisTemplateDb1; public RedisRepositoryAutowired() { // 생성자에 @Autowired 된 필드를 사용하면 안된다. 에러 발생. } public void save0(String key, String value) { stringRedisTemplateDb0.opsForValue().set(key, value); } public void save1(String key, String value) { stringRedisTemplateDb1.opsForValue().set(key, value); } }

Class RedisRepositoryParameter

생성자에 parameter(인자)를 이용한 Repository
Bean으로 지정한 이름을 사용한다.

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.data.redis.core.ValueOperations; import org.springframework.stereotype.Repository; @Repository @Slf4j public class RedisRepositoryParameter { private StringRedisTemplate stringRedisTemplateDb0; private StringRedisTemplate stringRedisTemplateDb1; private final ValueOperations redisString0; private final ValueOperations redisString1; // RedisConfigDb0,1에 정의된 @Bean method를 사용하려면 인자로 받는다. public RedisRepositoryParameter(StringRedisTemplate stringRedisTemplateDb0, StringRedisTemplate stringRedisTemplateDb1) { this.stringRedisTemplateDb0 = stringRedisTemplateDb0; this.redisString0 = stringRedisTemplateDb0.opsForValue(); this.stringRedisTemplateDb1 = stringRedisTemplateDb1; this.redisString1 = stringRedisTemplateDb1.opsForValue(); } public void save0(String key, String value) { redisString0.set(key, value); } public void save1(String key, String value) { redisString1.set(key, value); } }

Lettuce RedisClient

RedisClient에서는 select() 메소드로 DB를 이동(선택)할 수 있습니다.

레디스 서버에 연결 시에도 DB를 지정할 수 있습니다.

getRedisClient0은 0번 DB에 접속하고 getRedisClient1은 1번 DB에 접속한다. Bean name을 지정했다.

Class RedisClientConfig

package com.redisgate.dbselect; import io.lettuce.core.RedisClient; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; @Configuration @Slf4j public class RedisClientConfig { @Value("${redis.host}") private String host; @Value("${redis.port}") private int port; @Value("${redis.password}") private String password; @Value("${redis.clientName}") private String clientName; @Bean(name = "getRedisClient0") public RedisClient getRedisClient0() { int dbno = 0; // String uri = "redis://"+password+"@"+host+":"+port; // String uri = "redis://"+password+"@"+host+":"+port+"/"+dbno; String uri = "redis://"+password+"@"+host+":"+port+"/"+dbno+"?&clientName=redisgateX"; log.info(uri); return RedisClient.create(uri); } @Bean(name = "getRedisClient1") public RedisClient getRedisClient1() { int dbno = 1; String uri = "redis://"+password+"@"+host+":"+port+"/"+dbno+"?&clientName=redisgateY"; log.info(uri); return RedisClient.create(uri); } // URI syntax // Redis Standalone // redis://[[username:]password@]host [: port][/database][? [timeout=timeout[d|h|m|s|ms|us|ns]] [ &database=database] [&clientName=clientName] [&verifyPeer=NONE|CA|FULL]] // Redis Standalone (SSL) // rediss://[[username:]password@]host [: port][/database][? [timeout=timeout[d|h|m|s|ms|us|ns]] [ &database=database] [&clientName=clientName] [&verifyPeer=NONE|CA|FULL]] // Redis Standalone (Unix Domain Sockets) // redis-socket:// [[username:]password@]path[ ?[timeout=timeout[d|h|m|s|ms|us|ns]][&database=database] [&clientName=clientName] [&verifyPeer=NONE|CA|FULL]] // Redis Sentinel // redis-sentinel://[[username:]password@]host1 [: port1][, host2 [:port2]][, hostN [:portN]][/ database][? [timeout=timeout[d|h|m|s|ms|us|ns]] [ &sentinelMasterId=sentinelMasterId] [&database=database] [&clientName=clientName] [&verifyPeer=NONE|CA|FULL]] }

Class RedisClientRepository

dbselect(int dbno): DB를 이동(선택)할 수 있다.
save(String key, String value): 0번 DB에 저장한다.
save1(String key, String value): 1번 DB에 저장한다. package com.redisgate.dbselect; import io.lettuce.core.RedisClient; import io.lettuce.core.api.StatefulRedisConnection; import io.lettuce.core.api.async.RedisAsyncCommands; import io.lettuce.core.api.sync.RedisCommands; import lombok.extern.slf4j.Slf4j; import org.springframework.stereotype.Repository; @Repository @Slf4j public class RedisClientRepository { private RedisClient redisClient0; private RedisClient redisClient1; private StatefulRedisConnection<String, String> connection; private StatefulRedisConnection<String, String> connection1; private RedisCommands<String, String> syncCmd; private RedisCommands<String, String> syncCmd1; private RedisAsyncCommands<String, String> asyncCmd; public RedisClientRepository(RedisClient getRedisClient0, RedisClient getRedisClient1) { this.redisClient0 = getRedisClient0; this.connection = redisClient0.connect(); this.syncCmd = this.connection.sync(); this.asyncCmd = this.connection.async(); this.redisClient1 = getRedisClient1; this.connection1 = redisClient1.connect(); this.syncCmd1 = this.connection1.sync(); } public void dbselect(int dbno) { this.syncCmd.select(dbno); } public void save(String key, String value) { syncCmd.set(key, value); } public void save1(String key, String value) { syncCmd1.set(key, value); } }

Controller

Class RedisController

• @GetMapping("/save0") redisRepositoryAutowired로 DB0,1에 저장합니다.
• @GetMapping("/save1") redisRepositoryParameter로 DB0,1에 저장합니다.
• @GetMapping("/save2") redisClientRepository로 DB0,1에 저장합니다.
• @GetMapping("/save/{size}") 10개 스레드로 실행하면서 중간에 스레드1번에서 키 Thread1-500를 만나면 dbselect()를 실행해서 DB를 변경한다. 이후에는 이 스레드뿐만 아니라 다른 스레드에서도 DB10에 저장된다. (당연하지만 확인을 위해서 테스트해보았다.)
  if (key.equals("Thread1-500")) {
        redisClientRepository.dbselect(10);
  }

package com.redisgate.dbselect; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RestController; import java.sql.Timestamp; @RestController @Slf4j public class RedisController { @Autowired RedisRepositoryAutowired redisRepositoryAutowired; @Autowired RedisRepositoryParameter redisRepositoryParameter; @Autowired RedisClientRepository redisClientRepository; @GetMapping("/save0") public void save0() { redisRepositoryAutowired.save0("key01-db0", "value01-db0"); redisRepositoryAutowired.save1("key01-db1", "value01-db1"); } @GetMapping("/save1") public void save1() { redisRepositoryParameter.save0("key02-db0", "value02-db0"); redisRepositoryParameter.save1("key02-db1", "value02-db1"); } @GetMapping("/save2") public void save2() { redisClientRepository.save("redisClient-db1", "value-db0"); } @GetMapping("/save/{size}") public void saveTest(@PathVariable("size") int size) { Thread[] thread = new Thread[size]; for (int i=0; i < size; i++) { thread[i] = new Thread(new Runnable() { @Override public void run() { save(); } }); } for (int i=0; i < size; i++) { thread[i].setName("Thread"+i); thread[i].start(); } } public void save() { int count = 1000; // save Thread thread = Thread.currentThread(); String threadName = thread.getName(); log.info("Redis Multi Thread 테스트 - Save: {}", threadName); Timestamp startTime = new Timestamp(System.currentTimeMillis()); for (int i=0; i<count; i++) { String key = threadName+"-"+i; if (key.equals("Thread1-500")) { log.info("db select 10"); redisClientRepository.dbselect(10); } redisClientRepository.save(key, "value-"+threadName+"-"+i); } Timestamp endTime = new Timestamp(System.currentTimeMillis()); log.info("{} 소요시간: {}회 -> {} ms (시작:{} ~ 종료: {})", threadName, count, endTime.getTime()-startTime.getTime(), startTime, endTime); // millis } }