Feign+mybatisplus搭建項目遇到的坑及解決

更新時間：2023年03月30日 14:18:47 作者：清淡看朝霞

這篇文章主要介紹了Feign+mybatisplus搭建項目遇到的坑及解決方案，具有很好的參考價值，希望對大家有所幫助。如有錯誤或未考慮完全的地方，望不吝賜教

出現(xiàn)的錯誤

1.Failed to bind properties under ‘spring.datasource’ to javax.sql.DataSource:

2.@org.springframework.beans.factory.annotation.Autowired(required=true)等

原因（簡潔說明）

使用代碼生成器的service層需要繼承extends IService，這是一個坑，它不可以在接口工程中使用，實體類可以

如果想要使用mp的功能，就需要：

—— > 1.接口工程中創(chuàng)建無extends IService的接口 A

—— > 2.provider工程中放入代碼生成的service層接口B

—— > 3.provider工程的實現(xiàn)類需要 implements A,B

代碼

接口工程

import com.study.seckill.entity.User;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import java.util.List;

@Service
@FeignClient(value = "seckill-provider-localhost")
public interface IUserService /*extends IService<User>*/ {

    @RequestMapping(value = "/users",method = RequestMethod.GET)
    public List<User> quallAll();

}

接口工程依賴

<dependencies>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>

    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-generate</artifactId>
      <version>2.2.0</version>
    </dependency>
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-extension</artifactId>
      <version>3.1.1</version>
    </dependency>
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <optional>true</optional>
    </dependency>
  </dependencies>

–注意不要有druid數(shù)據(jù)源依賴，可能會報sqlSession等異常–

consumer工程代碼

controller

@RestController
public class UserConsumerController {

    @Autowired
    private IUserService iUserService;

    @GetMapping(value = "/users")
    public  String queryByName(){
        List<User> users = iUserService.quallAll();
        return users.toString();
    }
    
}

啟動類

@EnableFeignClients(basePackages = {"com.study.seckill"})
@SpringBootApplication
@EnableEurekaClient
public class Seckill_Consumer_8080 {
    public static void main(String[] args) {
        SpringApplication.run(Seckill_Consumer_8080.class, args);
    }
}

consumer依賴

 <dependencies>
    <dependency>
      <groupId>com.study</groupId>
      <artifactId>seckill-api</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>

    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-ribbon</artifactId>
      <version>1.4.6.RELEASE</version>
    </dependency>

    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-eureka</artifactId>
      <version>1.4.6.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>

    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-hystrix</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-hystrix-dashboard</artifactId>
    </dependency>
  </dependencies>

consumer的application.yml

server:
  port: 8080
#配置eureka
eureka:
  client:
    register-with-eureka: true
    service-url:
      defaultZone: http://localhost:7001/eureka/
  instance:
    instance-id: seckill-consumer-8080
    prefer-ip-address: true
spring:
  application:
    name: seckill-consumer-8080

#開啟降級
feign:
#  hystrix:
#    enabled: true

#feign客戶端負(fù)載均衡策略
#seckill-provider-localhost:
#  ribbon:
#
##   NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule #配置規(guī)則 隨機
#    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RoundRobinRule #配置規(guī)則 輪詢
##   NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RetryRule #配置規(guī)則 重試
##   NFLoadBalancerRuleClassName: com.netflix.loadbalancer.WeightedResponseTimeRule #配置規(guī)則 響應(yīng)時間權(quán)重
##   NFLoadBalancerRuleClassName: com.netflix.loadbalancer.BestAvailableRule #配置規(guī)則 最空閑連接策略
#    ConnectTimeout: 5000 #請求連接超時時間
#    ReadTimeout: 10000 #請求處理的超時時間
#    OkToRetryOnAllOperations: true #對所有請求都進行重試
#    MaxAutoRetriesNextServer: 2 #切換實例的重試次數(shù)
#    MaxAutoRetries: 2 #對當(dāng)前實例的重試次數(shù)

prodvider工程

如圖：UserServiceImpl 需要實現(xiàn)這個UserService和IUserService

service層結(jié)構(gòu)

import com.baomidou.mybatisplus.extension.service.IService;
import com.study.seckill.entity.User;
public interface UserService  extends IService<User> {
}

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.study.seckill.entity.User;
import com.study.seckill.mapper.UserMapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.study.seckill.service.IUserService;
import com.study.seckill.service.UserService;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService, UserService {

    @Override
    public List<User> quallAll() {
        QueryWrapper<User> userQueryWrapper = new QueryWrapper<>();
        return baseMapper.selectList(null);
    }
}

provider的application.properties

mybatis-plus.type-aliases-package=com.study.seckill.entity
mybatis-plus.global.config.refresh-mapper=true
mybatis-plus.mapper-locations=classpath:/mapper/**/*.xml

provider依賴

<dependencies>
    <dependency>
      <groupId>com.study</groupId>
      <artifactId>seckill-api</artifactId>
      <version>0.0.1-SNAPSHOT</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-web</artifactId>
    </dependency>

    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-eureka</artifactId>
    </dependency>
    <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
    </dependency>

    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-boot-starter</artifactId>
      <version>3.1.1</version>
    </dependency>
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus</artifactId>
      <version>3.1.1</version>
    </dependency>
    <!--用來支持AR-->
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-generate</artifactId>
      <version>2.2.0</version>
    </dependency>
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-extension</artifactId>
      <version>3.1.1</version>
    </dependency>
    <!--自動生成模板-->
    <dependency>
      <groupId>org.freemarker</groupId>
      <artifactId>freemarker</artifactId>
      <version>2.3.29</version>
    </dependency>

    <!--連接池-->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.1.12</version>
    </dependency>
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <optional>true</optional>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
    </dependency>
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
    </dependency>
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-core</artifactId>
    </dependency>

    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-test</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
      <exclusions>
        <exclusion>
          <groupId>org.junit.vintage</groupId>
          <artifactId>junit-vintage-engine</artifactId>
        </exclusion>
      </exclusions>
    </dependency>

  </dependencies>

  <build>
    <!-- 添加資源 -->
    <resources>
      <resource>
        <directory>src/main/resources</directory>
        <!-- src/main/resources下的指定資源放行 -->
        <includes>
          <include>**/*.properties</include>
          <include>**/*.yml</include>
          <include>**/**/*.xml</include>
        </includes>
        <filtering>false</filtering>
      </resource>
    </resources>
  </build>
</project>

provider工程需要配置druid數(shù)據(jù)源，不然會報異常，這里不再贅述。