SpringCloud集成MybatisPlus，实现MySQL多数据源配置

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.4.0</version>
</dependency>

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.15</version>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>

spring.datasource.master.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.master.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC
spring.datasource.master.username=root
spring.datasource.master.password=root

spring.datasource.slave.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.slave.url=jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC
spring.datasource.slave.username=root
spring.datasource.slave.password=root

spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.pool.init-size=10
spring.datasource.pool.max-size=20
spring.datasource.pool.min-size=5
spring.datasource.pool.max-wait=30000
spring.datasource.filters=stat,wall,log4j
spring.datasource.log-enabled=true
spring.datasource.log-prefix=druid.log
spring.datasource.stat-view-servlet.enabled=true
spring.datasource.stat-view-servlet.url-pattern=/druid/*
spring.datasource.web-stat-filter.enabled=true
spring.datasource.web-stat-filter.exclusions=*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*
spring.datasource.max-total=20
spring.datasource.max-idle=10
spring.datasource.min-idle=5
spring.datasource.time-between-eviction-runs-millis=60000
spring.datasource.min-evictable-idle-time-millis=300000
spring.datasource.validation-query=SELECT 1 FROM dual
spring.datasource.test-on-borrow=true
spring.datasource.test-on-return=true
spring.datasource.test-while-idle=true
spring.datasource.remove-abandoned=true
spring.datasource.remove-abandoned-timeout=60000
spring.datasource.log-abandoned=true

mybatis-plus.mapper-locations=classpath:mapper/*.xml
mybatis-plus.global-config.id-type=auto
mybatis-plus.global-config.db-config.logic-delete-value=1
mybatis-plus.global-config.db-config.logic-not-delete-value=0
mybatis-plus.global-config.base-namespace=test
mybatis-plus.global-config.mapper-namespace=test.mapper

@Mapper
public interface UserMapper extends BaseMapper<User> {
}

@SpringBootApplication
@EnableDiscoveryClient
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @MapperScan("com.example.demo.mapper")
    public class MyApp {
        // ...
    }
}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;

    @Override
    public User save(User user) {
        return userMapper.save(user);
    }

    @Override
    public User update(User user) {
        return userMapper.updateById(user);
    }

    @Override
    public User findById(Long id) {
        return userMapper.selectById(id);
    }

    @Override
    public void delete(Long id) {
        userMapper.deleteById(id);
    }
}

@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserService userService;

    @PostMapping
    public User save(@RequestBody User user) {
        return userService.save(user);
    }

    @PutMapping("/{id}")
    public User update(@PathVariable Long id, @RequestBody User user) {
        user.setId(id);
        return userService.update(user);
    }

    @GetMapping("/{id}")
    public User findById(@PathVariable Long id) {
        return userService.findById(id);
    }

    @DeleteMapping("/{id}")
    public void delete(@PathVariable Long id) {
        userService.delete(id);
    }
}

@MapperScan("com.example.demo.mapper.master")
public interface UserMapperMaster extends BaseMapper<User> {
}

@MapperScan("com.example.demo.mapper.slave")
public interface UserMapperSlave extends BaseMapper<User> {
}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapperMaster userMapperMaster;

    @Autowired
    private UserMapperSlave userMapperSlave;

    @Override
    public User save(User user) {
        return userMapperMaster.save(user);
    }

    @Override
    public User update(User user) {
        return userMapperMaster.updateById(user);
    }

    @Override
    public User findById(Long id) {
        return userMapperMaster.selectById(id);
    }

    @Override
    public void delete(Long id) {
        userMapperMaster.deleteById(id);
    }
}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapperMaster userMapperMaster;

    @Autowired
    private UserMapperSlave userMapperSlave;

    @Override
    public User save(User user) {
        return userMapperMaster.save(user);
    }

    @Override
    public User update(User user) {
        return userMapperMaster.updateById(user);
    }

    @Override
    public User findById(Long id) {
        return userMapperMaster.selectById(id);
    }

    @Override
    public void delete(Long id) {
        userMapperMaster.deleteById(id);
    }

    @MapperScan("com.example.demo.mapper.slave")
    @Override
    public User findByIdSlave(Long id) {
        return userMapperSlave.selectById(id);
    }
}