springCloud(5)-RestTemplate

consumer-provider 之间一般通过 RestTemplate来进行数据交互。
1.官网
https://docs.spring.io/spring-framework/docs/5.2.2.RELEASE/javadoc-api/org/springframework/web/client/RestTemplate.html
2.使用
 (Url,requestMap,ResponseBean.class)
请求地址、请求参数、HTTP响应转换被转换成的对象类型

3.config类编写，把RestTemplate加载进来

@Configuration
public class ApplicationContextConfig {
    @Bean
    //@LoadBalanced
    public RestTemplate getRestTemplate()
    {
        return new RestTemplate();
    }
}

  注意：注解：@Configuration  @Bean 

  以前spring 是xml配置，现在是注解了 //applicationContext.xml <bean id="" class="">

4.调用
   url
   post
   get（）带参数

public class OrderController {

    //调用地址
 //   public static final String PAYMENT_URL = "http://CLOUD-PAYMENT-SERVICE";
    public static final String PAYMENT_URL = "http://localhost:8001";
    @Resource
    private RestTemplate restTemplate;

    //读操作 get
    //多了一个consumer
    @GetMapping("/consumer/payment/create")
    public CommonResult<Payment> create(Payment payment)
    {
        //URL,参数，返回值
        return restTemplate.postForObject(PAYMENT_URL +"/payment/create",payment,CommonResult.class);
    }
    //写操作 post
    @GetMapping("/consumer/payment/get/{id}")
    public CommonResult<Payment> getPayment(@PathVariable("id") Long id)
    {
        return restTemplate.getForObject(PAYMENT_URL+"/payment/get/"+id,CommonResult.class);
    }
}

5.验证
   5.1启动两个服务
   5.2 provider: 浏览器输入网址看是否成功  http://localhost:8001/payment/get/31
   5.3 consumer：                            输入：http://localhost/consumer/payment/get/31
           没写端口号，默认80.这个值是application.yml中配置的。