总览

　　服务提供者： 服务的被调用方，为其他服务提供服务的服务
　　服务消费者： 服务的调用方，即依赖其他服务的服务

场景

　　

围绕该场景，需要两个微服务

• 用户微服务，作为服务提供者为电影微服务提供服务
• 电影微服务，作为消费者调用用户微服务提供的服务

用户微服务

　Spring Boot 
　Spring Data JPA
    H2
    lombok简化编码

用户库表

　schema.sql

drop table user if exists;
create table user(
    id bigint generated by default as identity,
    username varchar(40),
    name varchar(20),
    age int(3),
    balance decimal(10,2),
    primary key(id)
);

   datasource.sql

insert into user(id,username, name, age, balance) values(1,'user1', '张三', 20, 100.00);
insert into user(id,username, name, age, balance) values(2,'user2', '李四', 20, 100.00);
insert into user(id,username, name, age, balance) values(3,'user3', '王五', 20, 100.00);
insert into user(id,username, name, age, balance) values(4,'user4', '马六', 20, 100.00);

    model

@Entity
@Data
public class User implements Serializable{
    private static final long serialVersionUID=226695758444267342L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @Column
    private String username;

    @Column
    private String name;

    @Column
    private Integer age;

    @Column
    private BigDecimal balance;
}

Dao层

使用Spring Data JPA操作数据库

 

@Repository
public interface UserRepository  extends JpaRepository<User,Long>{
}

 

Controller 暴露Rest API

@RestController
public class UserController {

    @Autowired
    private UserRepository userRepository;

    @GetMapping("/user/{id}")
    public User findById(@PathVariable Long id){
        User user = new User();
        user.setId(id);

        User user1=new User();
        user1.setName("no this user");

        return userRepository.findOne(Example.of(user)).orElse(user1);
    }
}

配置文件application.yml

server:
   port: 7900
spring:
   jpa:
     generate-ddl: false
     show-sql: true
     hibernate:
       ddl-auto: none
   datasource:
     platform: h2
     schema: classpath:schema.sql
     data: classpath:data.sql
logging:
  level:
     root: INFO
     org.hibernate: INFO
     org.hibernate.type.descriptor.sql.BasicBinder: TRACE
     org.hibernate.type.descriptor.sql.BasicExtractor: TRACE
     com.smart: DEBUG

电影微服务

Controller通过 RestTemplate 调用用户微服务提供的服务

仅仅作为服务消费者，所有只要在Controller层调用对应的rest接口即可

@RestController
public class MovieController {
 
  @Autowired
  private RestTemplate restTemplate;

  @Value("${user.userServicePath}")
  private String userServicePath;

  @GetMapping("/movie/{id}")
  public User findById(@PathVariable Long id) {
    return this.restTemplate.getForObject(this.userServicePath + id, User.class);
  }
}

新建个User.java

@Data
public class User implements Serializable {

    private static final long serialVersionUID = 8912111288470833198L;
    private Long id;
    private String username;
    private String name;
    private Integer age;
    private BigDecimal balance;

}

启动类入口处，通过@Bean实例化RestTemplate

通过@Bean实例化RestTemplate

 

@SpringBootApplication
public class MicorserviceSimpleConsumerMovieApplication {
    
    @Bean
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
    
    public static void main(String[] args) {
        SpringApplication.run(MicorserviceSimpleConsumerMovieApplication.class, args);
    }
}

 

配置文件 application.yml

配置端口及用户微服务的地址

 

server:
  port: 7901
user: 
  userServicePath: http://localhost:7900/user/

 

测试

启动用户微服务，访问7901

访问数据库中存在的用户
http://localhost:7901/movie/1

{"id":1,"username":"user1","name":"张三","age":20,"balance":100.00}

参考：

　　https://blog.csdn.net/yangshangwei/article/details/84679248