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

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

//指定服務(wù)名稱
@FeignClient("SEARCH")
public interface SearchClient {
    //value -> 目標(biāo)服務(wù)的請(qǐng)求路徑，method -> 映射請(qǐng)求方式
    @RequestMapping(value = "/search",method = RequestMethod.GET)
    public String search();
}

@Autowired
private SearchClient searchClient;

@GetMapping("/customer")
public String customer() {
    
    String result = searchClient.search();
    return result;
}

String result = restTemplate.getForObject(url+"search", String.class);

String result = restTemplate.getForObject("http://SEARCH/search", String.class);

String result = searchClient.search();

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Customer {
    private Integer id;
    private String name;
    private Integer age;
}

@GetMapping("/search/{id}")
public Customer findById(@PathVariable Integer id){
    return new Customer(id,"張三",23);
}

@GetMapping("/getCustomer")
public Customer getCustomer(@RequestParam Integer id, @RequestParam String name){
    return new Customer(id,name,23);
}

@PostMapping("/save")
public Customer save(@RequestBody Customer customer){
    return customer;
}

@FeignClient(value = "SEARCH")
public interface SearchClient {

    @RequestMapping(value = "/search/{id}", method = RequestMethod.GET)
    public Customer findById(@PathVariable(value = "id") Integer id);

    @RequestMapping(value = "/getCustomer", method = RequestMethod.GET)
    public Customer getCustomer(@RequestParam(value = "id") Integer id, @RequestParam(value = "name") String name);
    
	//這里參數(shù)復(fù)雜，會(huì)自動(dòng)轉(zhuǎn)化成POST請(qǐng)求
    @RequestMapping(value = "/save", method = RequestMethod.GET)
    public Customer save(@RequestBody Customer customer);

}

@Component
public class SearchClientFallBack implements SearchClient {
    @Override
    public String search() {
        return "search出現(xiàn)問(wèn)題了?。?！";
    }
    @Override
    public Customer findById(Integer id) {
        return null;
    }
    @Override
    public Customer getCustomer(Integer id, String name) {
        return null;
    }
    @Override
    public Customer save(Customer customer) {
        return null;
    }
}

@FeignClient(value = "SEARCH",fallback = SearchClientFallBack.class)
public interface SearchClient {
	.........
}

# fallback
feign:
  hystrix:
    enabled: true

@Component
public class SearchClientFallBackFactory implements FallbackFactory<SearchClient> {

    //注入Fallback
    @Autowired
    private SearchClientFallBack searchClientFallBack;

    @Override
    public SearchClient create(Throwable throwable) {
        throwable.printStackTrace();
        return searchClientFallBack;
    }
}

@FeignClient(value = "SEARCH",
        /*fallback = SearchClientFallBack.class*/
        fallbackFactory = SearchClientFallBackFactory.class
)
public interface SearchClient {
	.........
}