springcloud 使用Feign遇到的坑

爱被打了一巴掌 2022-03-02 12:35 375阅读 0赞

问题一：无法添加spring-cloud-starter-feign依赖

*  解决办法：

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

问题二：编写@FeignClient接口出现请求方式错误，参数错误

*  解决办法

package com.example.eurekaconsumerclient.dao;
    import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.stereotype.Component;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    @Component
    @FeignClient("client-provider")
    public interface TestClient { 
        //必须使用@RequestMapping,不能使用@GetMapping
        //@PathVariable 必须指定参数名称
        @RequestMapping(method = RequestMethod.GET,value = "/test/{name}")
        String test(@PathVariable("name") String name);
    }

问题三：在@FeignClient接口中，方法参数是复杂对象，即使指定请求格式为Get,Feign依然会以post方法进行发送请求，控制台报错

*  解决办法

package com.example.eurekaconsumerclient.dao;
    import com.example.eurekaconsumerclient.pojo.User;
    import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.stereotype.Component;
    import org.springframework.web.bind.annotation.*;
    
    @Component
    @FeignClient("client-provider")
    public interface TestClient { 
        //必须使用@RequestMapping,不能使用@GetMapping
        //@PathVariable 必须指定参数名称
        @RequestMapping(method = RequestMethod.GET,value = "/test/{name}")
        String test(@PathVariable("name") String name);
        /** * 错误写法 * @param user User 对象 * @return */
        @RequestMapping(method = RequestMethod.Get,value = "/test/")
        User findByUser(User user);
        /** * 正确写法 * @param id User->id属性 * @param username User->username属性 * @return */
        @RequestMapping(method = RequestMethod.GET,value = "/test/")
        User findByUser(@RequestParam("id") Long id,@RequestParam("username") String username);
    }