分布式事务的实现方案和redis缓存配置

时间:2022-10-24 14:28:13 作者:快盘下载人气:30

分布式事务的实现方案和redis缓存配置

一.什么是分布式事务

针对于单数据库的事务我们叫着本地事务/传统事务;在分布式环境中一个请求可能涉及到多个数据库的写操作(多数据源);要保证多数据源的一致性必须用到分布式事务。

二.为什么需要分布式事务

系统微服务化后;一个看似简单的功能;内部可能需要调用多个服务并操作多个数据库实现;服务调用的分布式事务问题变的非常突出。

分布式事务的实现方案和redis缓存配置

一个下单请求同时设计到订单库;优惠券库;库存库的写操作;需要保证三个库写操作的一致性;就要用到分布式事务即;分布式事务就是要解决一个请求同时对多个数据库写操作的一致性

注意;微服务拆分原则;尽量让大部分操作都不要跨微服务操作;也就是跨库。分布式事务比本地事务耗费的资源更多。

三.分布式事务解决方案

2PC方案

2PC即两阶段提交协议,是将整个事务流程分为两个阶段,准备阶段( Prepare phase).提交阶段( pphase ) , 2是指两个阶段, P是指准备阶段, C是指提交阶段。

在第一阶段(准备阶段);事务管理器先事务参与者(资源)们发送准备请求;大家都返回OK状态;那么就进入第二阶段;提交事务;如果在第一阶段有任何一个参与者没有OK;那么事务协调器通知其他所有事务参与者(资源)回滚事务。2PC常见的标准是XA, JTA;Seata等。
基于Seata的2pc

Seata是由阿里中间件团队发起的开源项目Fescar ,后更名为Seata ,它是一个是开源的分布式事务框架。传统2PC的问题在Seata中得到了解决,它通过对本地关系数据库的分支事务的协调来驱动完成全局事务,是工作在应用层的中间件。主要优点是性能较好,且不长时间占用连接资源,它以高效并且对业务0侵入的方式解决微服务场景下面临的分布式事务问题,它目前提供AT模式(即2PC)及TCC模式的分布式事务解决方案。
- Transaction Coordinator(TC):事务协调器,它是独立的中间件,需要独立部署运行,它维护全局事务的运行状态,接收TM指令发起全局事务的提交与回滚,负责与RM通信协调各各分支事务的提交或回滚。相当于是一个软件需要单独部署
- Transaction Manager ™:事务管理器, TM需要嵌入应用程序中工作,它负责开启一个全局事务,并最终向TC发起全局提交或全局回滚的指令。
- Resource Manager (RM):资源管理器控制分支事务, 负责分支注册、状态汇报,并接收事务协调器TC的指令, 驱动分支(本地)事务的提交和回滚。
事务流程如下

具体的执行流程如下:
1. 用户服务的TM向TC申请开启一个全局事务,全局事务创建成功并生成一个全局唯一的XID。
2. 用户服务的RM向TC注册分支事务,该分支事务在用户服务执行新增用户逻辑,并将其纳入XID对应全局事务的管辖。
3. 用户服务执行分支事务,向用户表插入一条记录。
4. 逻辑执行到远程调用积分服务时(XID在微服务调用链路的;上下文中传播)。积分服务的RM向TC注册分支事务,该分支事务执行增加积分的逻辑,并将其纳入XID对应全局事务的管辖。
5. 积分服务执行分支事务,向积分记录表插入一条记录,执行完毕后,返回用户服务。
Seata 分布式事务;https://blog.csdn.net/u014494148/article/details/105781920

四.注册集成Seata

1.下载

下载;https://github.com/seata/seata/tags
启动;seata-server.bat -p 8091 -h 127.0.0.1 -m file

导入依赖

 <dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.9</version>
</dependency>

 yml配置
 seata:
  enableAutoDataSourceProxy: false #关闭DataSource代理的自动配置;我们要手动配置
spring:
  cloud:
    alibaba:
      seata:
        tx-service-group: fsp_tx_group #这里和file.conf中事务组名一样

 拷贝配置
 1.resources/file.conf
 transport {
  # tcp udt unix-domain-socket
  type = ;TCP;
  #NIO NATIVE
  server = ;NIO;
  #enable heartbeat
  heartbeat = true
  # the client batch send request enable
  enableClientBatchSendRequest = true
  #thread factory for netty
  threadFactory {
    bossThreadPrefix = ;NettyBoss;
    workerThreadPrefix = ;NettyServerNIOWorker;
    serverExecutorThread-prefix = ;NettyServerBizHandler;
    shareBossWorker = false
    clientSelectorThreadPrefix = ;NettyClientSelector;
    clientSelectorThreadSize = 1
    clientWorkerThreadPrefix = ;NettyClientWorkerThread;
    # netty boss thread size,will not be used for UDT
    bossThreadSize = 1
    #auto default pin or 8
    workerThreadSize = ;default;
  }
  shutdown {
    # when destroy server, wait seconds
    wait = 3
  }
  serialization = ;seata;
  compressor = ;none;
}
service {
  #transaction service group mapping
  vgroupMapping.fsp_tx_group = ;default;
  #only support when registry.type=file, please don;t set multiple addresses
  default.grouplist = ;127.0.0.1:8091;
  #degrade, current not support
  enableDegrade = false
  #disable seata
  disableGlobalTransaction = false
}
 
client {
  rm {
    asyncCommitBufferLimit = 10000
    lock {
      retryInterval = 10
      retryTimes = 30
      retryPolicyBranchRollbackOnConflict = true
    }
    reportRetryCount = 5
    tableMetaCheckEnable = false
    reportSuccessEnable = false
  }
  tm {
    commitRetryCount = 5
    rollbackRetryCount = 5
  }
  undo {
    dataValidation = true
    logSerialization = ;jackson;
    logTable = ;undo_log;
  }
  log {
    exceptionRate = 100
  }
}
 2.resources/registry.conf
 registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = ;file;
 
  nacos {
    serverAddr = ;localhost;
    namespace = ;;
    cluster = ;default;
  }
  eureka {
    serviceUrl = ;http://localhost:8761/eureka;
    application = ;default;
    weight = ;1;
  }
  redis {
    serverAddr = ;localhost:6379;
    db = ;0;
    password = ;;
    cluster = ;default;
    timeout = ;0;
  }
  zk {
    cluster = ;default;
    serverAddr = ;127.0.0.1:2181;
    session.timeout = 6000
    connect.timeout = 2000
    username = ;;
    password = ;;
  }
  consul {
    cluster = ;default;
    serverAddr = ;127.0.0.1:8500;
  }
  etcd3 {
    cluster = ;default;
    serverAddr = ;http://localhost:2379;
  }
  sofa {
    serverAddr = ;127.0.0.1:9603;
    application = ;default;
    region = ;DEFAULT_ZONE;
    datacenter = ;DefaultDataCenter;
    cluster = ;default;
    group = ;SEATA_GROUP;
    addressWaitTime = ;3000;
  }
  file {
    name = ;file.conf;
  }
}
 
config {
  # file、nacos 、apollo、zk、consul、etcd3、springCloudConfig
  type = ;file;
 
  nacos {
    serverAddr = ;localhost;
    namespace = ;;
    group = ;SEATA_GROUP;
  }
  consul {
    serverAddr = ;127.0.0.1:8500;
  }
  apollo {
    app.id = ;seata-server;
    apollo.meta = ;http://192.168.1.204:8801;
    namespace = ;application;
  }
  zk {
    serverAddr = ;127.0.0.1:2181;
    session.timeout = 6000
    connect.timeout = 2000
    username = ;;
    password = ;;
  }
  etcd3 {
    serverAddr = ;http://localhost:2379;
  }
  file {
    name = ;file.conf;
  }
}

排除DataSource自动配置 ;SpringBootApplication(exclude = { DataSourceAutoConfiguration.class})

 .MybatisPlus版本
 把DataSource交给Seata代理。
 package io.coderyeah.ymcc.config;
 
import com.alibaba.druid.pool.DruidDataSource;
import com.baomidou.mybatisplus.spring.MybatisSqlSessionFactoryBean;
import io.seata.rm.datasource.DataSourceProxy;
import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
import org.springFramework.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 
import javax.sql.DataSource;
 
/**
 * 数据源代理
 */
;Configuration
public class DataSourceConfiguration {
 
    //mapper.xml路径
    ;Value(;${mybatis-plus.mapper-locations};)
    private String mapperLocations;
 
    //手动配置bean
    ;Bean
    ;ConfigurationProperties(;spring.datasource;)
    public DataSource druidDataSource(){
        return new DruidDataSource();
    }
 
    ;Bean
    public MybatisSqlSessionFactoryBean sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
        //处理MybatisPlus
        MybatisSqlSessionFactoryBean factory = new MybatisSqlSessionFactoryBean();
        factory.setDataSource(dataSourceProxy);
        factory.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
        //事务管理工厂
        factory.setTransactionFactory(new SpringManagedTransactionFactory());
        return factory;
    }
 
    ;Primary
    ;Bean(;dataSource;)
    public DataSourceProxy dataSourceProxy(DataSource druidDataSource) {
        return new DataSourceProxy(druidDataSource);
    }
 
}
 Mybatis版本
 import com.alibaba.druid.pool.DruidDataSource;
import io.seata.rm.datasource.DataSourceProxy;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 
import javax.sql.DataSource;
 
//使用seata对DataSource进行代理
;Configuration
public class DataSourceProxyConfig {
 
    //mapper.xml路径
    ;Value(;${mybatis.mapper-locations};)
    private String mapperLocations;
 
    //手动配置bean
    ;Bean
    ;ConfigurationProperties(prefix = ;spring.datasource;)
    public DataSource druidDataSource(){
        return new DruidDataSource();
    }
 
    ;Bean
    public SqlSessionFactory sessionFactory(DataSourceProxy dataSourceProxy) throws Exception {
        SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
        sessionFactoryBean.setDataSource(dataSourceProxy);
        sessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
        //事务管理工厂
        sessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
        return sessionFactoryBean.getObject();
    }
 
    ;Bean
    public DataSourceProxy dataSource() {
        return new DataSourceProxy(druidDataSource());
    }
}

业务方法方法上贴 : ;GlobalTransactional(rollbackFor = Exception.class) 开启Seata全局事务 2.6.注释事务开启注解注意;不能加;EnableTransactionManagement 注解了 ; 也不需要加;Transactional 2.7.undolog表数据库中创建表;涉及到事务的表都需要添加undolog

 
-- 注意此处0.3.0; 增加唯一索引 ux_undo_log
CREATE TABLE ;undo_log; (
  ;id; bigint(20) NOT NULL AUTO_INCREMENT,
  ;branch_id; bigint(20) NOT NULL,
  ;xid; varchar(100) NOT NULL,
  ;context; varchar(128) NOT NULL,
  ;rollback_info; longblob NOT NULL,
  ;log_status; int(11) NOT NULL,
  ;log_created; datetime NOT NULL,
  ;log_modified; datetime NOT NULL,
  ;ext; varchar(100) DEFAULT NULL,
  PRIMARY KEY (;id;),
  UNIQUE KEY ;ux_undo_log; (;xid;,;branch_id;)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
 
五.redis分布式缓存 
 导入依赖
 
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
            <version>2.10.0</version>
        </dependency>
 
 yml配置
 spring:
  application:
    name: service-user #服务名
  redis:
    host: 43.136.61.70
    port: 6379
    password: 123456
    database: 0
    lettuce:
      pool:
        max-active: 8
        max-idle: 8
        max-wait: 2000ms
 
 Redis序列化配置
 我们通常以JSON格式将数据存储到Redis中;这种格式是所有编程语言通用的;所以我们可以把Redis的序列化方式配置为JSON ,这样的话我们就可以不用自己去转JSON了.
 //缓存的配置
;Configuration
public class RedisConfig {
 
    ;Resource
    private RedisConnectionFactory factory;
 
 
    //使用JSON进行序列化
    ;Bean
    public RedisTemplate<Object, Object> redisTemplate() {
        RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(factory);
        //JSON格式序列化
        GenericJackson2JsonRedisSerializer genericJackson2JsonRedisSerializer = new GenericJackson2JsonRedisSerializer();
         //key的序列化
        redisTemplate.setKeySerializer(genericJackson2JsonRedisSerializer);
        //value的序列化
        redisTemplate.setValueSerializer(genericJackson2JsonRedisSerializer);
        //hash结构key的虚拟化
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        //hash结构value的虚拟化
        redisTemplate.setHashValueSerializer(genericJackson2JsonRedisSerializer);
        return redisTemplate;
    }
}
 举例
 		List<CourseType> list = null;
        final Object o = redisTemplate.opsForValue().get(YmccConstants.CACHE_COURSE_TYPE);
        if (null != o) {
            // 从redis中读取返回数据
            list = (List<CourseType>) o;
            System.out.println(;-------redis;);
        } else {
            list = getCourseTypes();
            // 存入redis
            redisTemplate.opsForValue().set(YmccConstants.CACHE_COURSE_TYPE, list);
            System.out.println(;-------mysql;);
        }
 
 
六.SpringCache缓存 
 SpringCahce对缓存流程进行了简化封装;提供了一些注解;我们通过简单的打注解就能实现缓存的添加;修改;删除等,注解如下; 
   ;Cacheable:触发缓存写入。
 
 ;CacheEvict:触发缓存清除。
 
 ;CachePut:更新缓存(不会影响到方法的运行)。
 
 ;Caching:重新组合要应用于方法的多个缓存操作。
 
 ;CacheConfig:设置类级别上共享的一些常见缓存设置。
 
 
 配置SpringCache
 继承 CachingConfigurerSupport 对SpringCache进行配置
 package io.coderyeah.ymcc.config;
 
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.interceptor.*;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
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.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
 
import javax.annotation.Resource;
 
;Configuration
public class CacheConfig extends CachingConfigurerSupport {
 
    ;Resource
    private RedisConnectionFactory factory;
 
    /*
     * 自定义生成redis-key ; 类名.方法名
     */
    ;Override
    ;Bean
    public KeyGenerator keyGenerator() {
        return (o, method, objects) -> {
            StringBuilder sb = new StringBuilder();
            sb.append(o.getClass().getName()).append(;.;);
            sb.append(method.getName()).append(;.;);
            for (Object obj : objects) {
                sb.append(obj.toString());
            }
            System.out.println(;keyGenerator=; ; sb.toString());
            return sb.toString();
        };
    }
 
    ;Bean
    ;Override
    public CacheResolver cacheResolver() {
        return new SimpleCacheResolver(cacheManager());
    }
 
    ;Bean
    ;Override
    public CacheErrorHandler errorHandler() {
        // 用于捕获从Cache中进行CRUD时的异常的回调处理器。
        return new SimpleCacheErrorHandler();
    }
    //缓存管理器
    ;Bean
    ;Override
    public CacheManager cacheManager() {
        RedisCacheConfiguration cacheConfiguration = RedisCacheConfiguration.defaultCacheConfig()
                        .disableCachingNullValues() //不允许空值
                        .serializeValuesWith(RedisSerializationContext.SerializationPair
                                             //值使用JSON序列化
                                             .fromSerializer(new GenericJackson2JsonRedisSerializer()));
        
        return RedisCacheManager.builder(factory).cacheDefaults(cacheConfiguration).build();
    }
} 
 
 开启SpringCache
 在启动类注解;;EnableCaching
 
 【特别注意】
 缓存注解不能加在内部方法上;比如;方法A调用方法B;给方法B加上缓存注解会失效;因为内部方法调用代理会失效。在A方法上打注解即可。
 
 添加缓存
 ;Cacheable(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public List<CourseType> treeData() {
   /* List<CourseType> list = null;
    final Object o = redisTemplate.opsForValue().get(YmccConstants.CACHE_COURSE_TYPE);
    if (null != o) {
        // 从redis中读取返回数据
        list = (List<CourseType>) o;
        System.out.println(;-------redis;);
    } else {
        list = getCourseTypes();
        // 存入redis
        redisTemplate.opsForValue().set(YmccConstants.CACHE_COURSE_TYPE, list);
        System.out.println(;-------mysql;);
    }*/
    log.debug(;=============查询了数据库============;);
    return getCourseTypes();
}
 
// 从数据库中查询
private List<CourseType> getCourseTypes() {
    // 查询所有分类
    List<CourseType> courseTypes = selectList(null);
    // 将集合转换为map
    Map<Long, CourseType> map = courseTypes.stream().collect(Collectors.toMap(CourseType::getId, courseType -> courseType));
    // 返回给前端的集合
    List<CourseType> list = new ArrayList<>();
    // 遍历
    courseTypes.forEach(courseType -> {
        if (courseType.getPid() == null || courseType.getPid() == 0) {
            // 顶级
            list.add(courseType);
        } else {
            // 找到父级
            CourseType type = map.get(courseType.getPid());
            if (type != null) {
                type.getChildren().add(courseType);
            }
        }
    });
    return list;
}
 
 剔除缓存
 // 剔除缓存
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean insert(CourseType entity) {
    return super.insert(entity);
}
 
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean deleteById(Serializable id) {
    return super.deleteById(id);
}
 
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean updateById(CourseType entity) {
    return super.updateById(entity);
}
 
 
} 
6. #### 剔除缓存
 
;;;java
// 剔除缓存
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean insert(CourseType entity) {
    return super.insert(entity);
}
 
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean deleteById(Serializable id) {
    return super.deleteById(id);
}
 
;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
;Override
public boolean updateById(CourseType entity) {
    return super.updateById(entity);
}


  
  加载全部内容

	`<dependency>`
	<groupId>com.alibaba.cloud</groupId>
	<artifactId>spring-cloud-starter-alibaba-seata</artifactId>
	</dependency>
	<dependency>
	<groupId>com.alibaba</groupId>
	<artifactId>druid</artifactId>
	<version>1.1.9</version>
	</dependency>

	`seata:`
	enableAutoDataSourceProxy: false #关闭DataSource代理的自动配置;我们要手动配置
	spring:
	cloud:
	alibaba:
	seata:
	tx-service-group: fsp_tx_group #这里和file.conf中事务组名一样

	`transport {`
	# tcp udt unix-domain-socket
	type = ;TCP;
	#NIO NATIVE
	server = ;NIO;
	#enable heartbeat
	heartbeat = true
	# the client batch send request enable
	enableClientBatchSendRequest = true
	#thread factory for netty
	threadFactory {
	bossThreadPrefix = ;NettyBoss;
	workerThreadPrefix = ;NettyServerNIOWorker;
	serverExecutorThread-prefix = ;NettyServerBizHandler;
	shareBossWorker = false
	clientSelectorThreadPrefix = ;NettyClientSelector;
	clientSelectorThreadSize = 1
	clientWorkerThreadPrefix = ;NettyClientWorkerThread;
	# netty boss thread size,will not be used for UDT
	bossThreadSize = 1
	#auto default pin or 8
	workerThreadSize = ;default;
	}
	shutdown {
	# when destroy server, wait seconds
	wait = 3
	}
	serialization = ;seata;
	compressor = ;none;
	}
	service {
	#transaction service group mapping
	vgroupMapping.fsp_tx_group = ;default;
	#only support when registry.type=file, please don;t set multiple addresses
	default.grouplist = ;127.0.0.1:8091;
	#degrade, current not support
	enableDegrade = false
	#disable seata
	disableGlobalTransaction = false
	}

	client {
	rm {
	asyncCommitBufferLimit = 10000
	lock {
	retryInterval = 10
	retryTimes = 30
	retryPolicyBranchRollbackOnConflict = true
	}
	reportRetryCount = 5
	tableMetaCheckEnable = false
	reportSuccessEnable = false
	}
	tm {
	commitRetryCount = 5
	rollbackRetryCount = 5
	}
	undo {
	dataValidation = true
	logSerialization = ;jackson;
	logTable = ;undo_log;
	}
	log {
	exceptionRate = 100
	}
	}

	`registry {`
	# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
	type = ;file;

	nacos {
	serverAddr = ;localhost;
	namespace = ;;
	cluster = ;default;
	}
	eureka {
	serviceUrl = ;http://localhost:8761/eureka;
	application = ;default;
	weight = ;1;
	}
	redis {
	serverAddr = ;localhost:6379;
	db = ;0;
	password = ;;
	cluster = ;default;
	timeout = ;0;
	}
	zk {
	cluster = ;default;
	serverAddr = ;127.0.0.1:2181;
	session.timeout = 6000
	connect.timeout = 2000
	username = ;;
	password = ;;
	}
	consul {
	cluster = ;default;
	serverAddr = ;127.0.0.1:8500;
	}
	etcd3 {
	cluster = ;default;
	serverAddr = ;http://localhost:2379;
	}
	sofa {
	serverAddr = ;127.0.0.1:9603;
	application = ;default;
	region = ;DEFAULT_ZONE;
	datacenter = ;DefaultDataCenter;
	cluster = ;default;
	group = ;SEATA_GROUP;
	addressWaitTime = ;3000;
	}
	file {
	name = ;file.conf;
	}
	}

	config {
	# file、nacos 、apollo、zk、consul、etcd3、springCloudConfig
	type = ;file;

	nacos {
	serverAddr = ;localhost;
	namespace = ;;
	group = ;SEATA_GROUP;
	}
	consul {
	serverAddr = ;127.0.0.1:8500;
	}
	apollo {
	app.id = ;seata-server;
	apollo.meta = ;http://192.168.1.204:8801;
	namespace = ;application;
	}
	zk {
	serverAddr = ;127.0.0.1:2181;
	session.timeout = 6000
	connect.timeout = 2000
	username = ;;
	password = ;;
	}
	etcd3 {
	serverAddr = ;http://localhost:2379;
	}
	file {
	name = ;file.conf;
	}
	}

	`package io.coderyeah.ymcc.config;`

	import com.alibaba.druid.pool.DruidDataSource;
	import com.baomidou.mybatisplus.spring.MybatisSqlSessionFactoryBean;
	import io.seata.rm.datasource.DataSourceProxy;
	import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
	import org.springFramework.beans.factory.annotation.Value;
	import org.springframework.boot.context.properties.ConfigurationProperties;
	import org.springframework.context.annotation.Bean;
	import org.springframework.context.annotation.Configuration;
	import org.springframework.context.annotation.Primary;
	import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

	import javax.sql.DataSource;

	/**
	* 数据源代理
	*/
	;Configuration
	public class DataSourceConfiguration {

	//mapper.xml路径
	;Value(;${mybatis-plus.mapper-locations};)
	private String mapperLocations;

	//手动配置bean
	;Bean
	;ConfigurationProperties(;spring.datasource;)
	public DataSource druidDataSource(){
	return new DruidDataSource();
	}

	;Bean
	public MybatisSqlSessionFactoryBean sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
	//处理MybatisPlus
	MybatisSqlSessionFactoryBean factory = new MybatisSqlSessionFactoryBean();
	factory.setDataSource(dataSourceProxy);
	factory.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
	//事务管理工厂
	factory.setTransactionFactory(new SpringManagedTransactionFactory());
	return factory;
	}

	;Primary
	;Bean(;dataSource;)
	public DataSourceProxy dataSourceProxy(DataSource druidDataSource) {
	return new DataSourceProxy(druidDataSource);
	}

	}

	`import com.alibaba.druid.pool.DruidDataSource;`
	import io.seata.rm.datasource.DataSourceProxy;
	import org.apache.ibatis.session.SqlSessionFactory;
	import org.mybatis.spring.SqlSessionFactoryBean;
	import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
	import org.springframework.beans.factory.annotation.Value;
	import org.springframework.boot.context.properties.ConfigurationProperties;
	import org.springframework.context.annotation.Bean;
	import org.springframework.context.annotation.Configuration;
	import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

	import javax.sql.DataSource;

	//使用seata对DataSource进行代理
	;Configuration
	public class DataSourceProxyConfig {

	//mapper.xml路径
	;Value(;${mybatis.mapper-locations};)
	private String mapperLocations;

	//手动配置bean
	;Bean
	;ConfigurationProperties(prefix = ;spring.datasource;)
	public DataSource druidDataSource(){
	return new DruidDataSource();
	}

	;Bean
	public SqlSessionFactory sessionFactory(DataSourceProxy dataSourceProxy) throws Exception {
	SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
	sessionFactoryBean.setDataSource(dataSourceProxy);
	sessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
	//事务管理工厂
	sessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
	return sessionFactoryBean.getObject();
	}

	;Bean
	public DataSourceProxy dataSource() {
	return new DataSourceProxy(druidDataSource());
	}
	}

	`-- 注意此处0.3.0; 增加唯一索引 ux_undo_log`
	CREATE TABLE ;undo_log; (
	;id; bigint(20) NOT NULL AUTO_INCREMENT,
	;branch_id; bigint(20) NOT NULL,
	;xid; varchar(100) NOT NULL,
	;context; varchar(128) NOT NULL,
	;rollback_info; longblob NOT NULL,
	;log_status; int(11) NOT NULL,
	;log_created; datetime NOT NULL,
	;log_modified; datetime NOT NULL,
	;ext; varchar(100) DEFAULT NULL,
	PRIMARY KEY (;id;),
	UNIQUE KEY ;ux_undo_log; (;xid;,;branch_id;)
	) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;


	<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-data-redis</artifactId>
	</dependency>
	<dependency>
	<groupId>org.apache.commons</groupId>
	<artifactId>commons-pool2</artifactId>
	<version>2.10.0</version>
	</dependency>

	`spring:`
	application:
	name: service-user #服务名
	redis:
	host: 43.136.61.70
	port: 6379
	password: 123456
	database: 0
	lettuce:
	pool:
	max-active: 8
	max-idle: 8
	max-wait: 2000ms

	`//缓存的配置`
	;Configuration
	public class RedisConfig {

	;Resource
	private RedisConnectionFactory factory;


	//使用JSON进行序列化
	;Bean
	public RedisTemplate<Object, Object> redisTemplate() {
	RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
	redisTemplate.setConnectionFactory(factory);
	//JSON格式序列化
	GenericJackson2JsonRedisSerializer genericJackson2JsonRedisSerializer = new GenericJackson2JsonRedisSerializer();
	//key的序列化
	redisTemplate.setKeySerializer(genericJackson2JsonRedisSerializer);
	//value的序列化
	redisTemplate.setValueSerializer(genericJackson2JsonRedisSerializer);
	//hash结构key的虚拟化
	redisTemplate.setHashKeySerializer(new StringRedisSerializer());
	//hash结构value的虚拟化
	redisTemplate.setHashValueSerializer(genericJackson2JsonRedisSerializer);
	return redisTemplate;
	}
	}

	`List<CourseType> list = null;`
	final Object o = redisTemplate.opsForValue().get(YmccConstants.CACHE_COURSE_TYPE);
	if (null != o) {
	// 从redis中读取返回数据
	list = (List<CourseType>) o;
	System.out.println(;-------redis;);
	} else {
	list = getCourseTypes();
	// 存入redis
	redisTemplate.opsForValue().set(YmccConstants.CACHE_COURSE_TYPE, list);
	System.out.println(;-------mysql;);
	}

	`package io.coderyeah.ymcc.config;`

	import org.springframework.cache.CacheManager;
	import org.springframework.cache.annotation.CachingConfigurerSupport;
	import org.springframework.cache.interceptor.*;
	import org.springframework.context.annotation.Bean;
	import org.springframework.context.annotation.Configuration;
	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.serializer.GenericJackson2JsonRedisSerializer;
	import org.springframework.data.redis.serializer.RedisSerializationContext;

	import javax.annotation.Resource;

	;Configuration
	public class CacheConfig extends CachingConfigurerSupport {

	;Resource
	private RedisConnectionFactory factory;

	/*
	* 自定义生成redis-key ; 类名.方法名
	*/
	;Override
	;Bean
	public KeyGenerator keyGenerator() {
	return (o, method, objects) -> {
	StringBuilder sb = new StringBuilder();
	sb.append(o.getClass().getName()).append(;.;);
	sb.append(method.getName()).append(;.;);
	for (Object obj : objects) {
	sb.append(obj.toString());
	}
	System.out.println(;keyGenerator=; ; sb.toString());
	return sb.toString();
	};
	}

	;Bean
	;Override
	public CacheResolver cacheResolver() {
	return new SimpleCacheResolver(cacheManager());
	}

	;Bean
	;Override
	public CacheErrorHandler errorHandler() {
	// 用于捕获从Cache中进行CRUD时的异常的回调处理器。
	return new SimpleCacheErrorHandler();
	}
	//缓存管理器
	;Bean
	;Override
	public CacheManager cacheManager() {
	RedisCacheConfiguration cacheConfiguration = RedisCacheConfiguration.defaultCacheConfig()
	.disableCachingNullValues() //不允许空值
	.serializeValuesWith(RedisSerializationContext.SerializationPair
	//值使用JSON序列化
	.fromSerializer(new GenericJackson2JsonRedisSerializer()));

	return RedisCacheManager.builder(factory).cacheDefaults(cacheConfiguration).build();
	}
	}

	`;Cacheable(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)`
	;Override
	public List<CourseType> treeData() {
	/* List<CourseType> list = null;
	final Object o = redisTemplate.opsForValue().get(YmccConstants.CACHE_COURSE_TYPE);
	if (null != o) {
	// 从redis中读取返回数据
	list = (List<CourseType>) o;
	System.out.println(;-------redis;);
	} else {
	list = getCourseTypes();
	// 存入redis
	redisTemplate.opsForValue().set(YmccConstants.CACHE_COURSE_TYPE, list);
	System.out.println(;-------mysql;);
	}*/
	log.debug(;=============查询了数据库============;);
	return getCourseTypes();
	}

	// 从数据库中查询
	private List<CourseType> getCourseTypes() {
	// 查询所有分类
	List<CourseType> courseTypes = selectList(null);
	// 将集合转换为map
	Map<Long, CourseType> map = courseTypes.stream().collect(Collectors.toMap(CourseType::getId, courseType -> courseType));
	// 返回给前端的集合
	List<CourseType> list = new ArrayList<>();
	// 遍历
	courseTypes.forEach(courseType -> {
	if (courseType.getPid() == null \|\| courseType.getPid() == 0) {
	// 顶级
	list.add(courseType);
	} else {
	// 找到父级
	CourseType type = map.get(courseType.getPid());
	if (type != null) {
	type.getChildren().add(courseType);
	}
	}
	});
	return list;
	}

	`// 剔除缓存`
	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean insert(CourseType entity) {
	return super.insert(entity);
	}

	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean deleteById(Serializable id) {
	return super.deleteById(id);
	}

	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean updateById(CourseType entity) {
	return super.updateById(entity);
	}


	6. #### 剔除缓存

	;;;java
	// 剔除缓存
	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean insert(CourseType entity) {
	return super.insert(entity);
	}

	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean deleteById(Serializable id) {
	return super.deleteById(id);
	}

	;CacheEvict(cacheNames = YmccConstants.CACHE_COURSE_TYPE, key = ;;all;;)
	;Override
	public boolean updateById(CourseType entity) {
	return super.updateById(entity);
	}

分布式事务的实现方案和redis缓存配置

分布式事务的实现方案和redis缓存配置

一.什么是分布式事务

二.为什么需要分布式事务

三.分布式事务解决方案

2PC方案

基于Seata的2pc

四.注册集成Seata

1.下载

导入依赖

yml配置

拷贝配置

1.resources/file.conf

2.resources/registry.conf

排除DataSource自动配置

.MybatisPlus版本

业务方法

2.6.注释事务开启注解

2.7.undolog表

五.redis分布式缓存

导入依赖

yml配置

Redis序列化配置

六.SpringCache缓存

配置SpringCache

开启SpringCache

【特别注意】

剔除缓存