The Feign call interface solves the problem of handling internal exceptions
- 2021-10-11 18:24:10
- OfStack
Problem description:
When using feign to call the interface, there is an interface problem of 400 ~ 500 ~. Error feign: FeignException. Because it is an error, you can only use catch Throwable, but you can't use catch Exception to catch exceptions.
Cause of problem:
Externally unable to catch exceptions because the default error handling class for feign is FunFeignFallback, throw, new, AfsBaseExceptio.
package com.ruicar.afs.cloud.common.core.feign;
import com.alibaba.fastjson.JSONObject;
import com.ruicar.afs.cloud.common.core.exception.AfsBaseException;
import com.ruicar.afs.cloud.common.core.util.IResponse;
import feign.FeignException;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;
import org.springframework.lang.Nullable;
import java.lang.reflect.Method;
import java.util.Objects;
@Data
@AllArgsConstructor
@Slf4j
public class FunFeignFallback<T> implements MethodInterceptor {
private final Class<T> targetType;
private final String targetName;
private final Throwable cause;
private static byte JSON_START = '{';
@Nullable
@Override
public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
String errorMessage = cause.getMessage();
if (!(cause instanceof FeignException)) {
log.error("FunFeignFallback:[{}.{}] serviceId:[{}] message:[{}]", targetType.getName(), method.getName(), targetName, errorMessage);
log.error("feign Call failed ", cause);
return IResponse.fail(" The request failed. Please try again later ");
}
int status = ((FeignException.FeignClientException) this.cause).status();
boolean isAuthFail = (status==426||status==403||status==401)&&"afs-auth".equals(targetName);
FeignException exception = (FeignException) cause;
if(isAuthFail){
log.warn(" Authorization failure ========== Original return information :[{}]",exception.contentUTF8());
}else {
log.error("FunFeignFallback:[{}.{}] serviceId:[{}] message:[{}]", targetType.getName(), method.getName(), targetName, errorMessage);
log.error("", cause);
log.error(" Original return information {}",exception.contentUTF8());
}
if(method.getReturnType().equals(Void.class)){
throw new AfsBaseException(" Interface call failed ");
}
if(method.getReturnType().equals(IResponse.class)){
if(exception instanceof FeignException.Forbidden){
return IResponse.fail(" No permissions ").setCode("403");
}
if(exception instanceof FeignException.NotFound){
return IResponse.fail(" Request path does not exist ").setCode("404");
}
if(exception instanceof FeignException.BadRequest){
return IResponse.fail(" Parameter error ").setCode("400");
}
if(exception.content()==null||exception.content().length==0){
return IResponse.fail(" The request failed. Please try again later ");
}
if(JSON_START==exception.content()[0]){
return JSONObject.parseObject(exception.content(),IResponse.class);
}else{
return IResponse.fail(exception.contentUTF8());
}
}else{
try {
if(method.getReturnType().equals(String.class)){
return exception.contentUTF8();
}else if(method.getReturnType().equals(JSONObject.class)){
if(JSON_START==exception.content()[0]){
return JSONObject.parseObject(exception.content(), JSONObject.class);
}
}else if(!method.getReturnType().equals(Object.class)){
return JSONObject.parseObject(exception.content(), method.getReturnType());
}
if(JSON_START==exception.content()[0]){
JSONObject jsonObject = JSONObject.parseObject(exception.content(), JSONObject.class);
if(jsonObject.containsKey("code")&&jsonObject.containsKey("msg")) {
return jsonObject.toJavaObject(IResponse.class);
}
}
}catch (Throwable e){}
throw new AfsBaseException(" Interface call failed ");
}
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
FunFeignFallback<?> that = (FunFeignFallback<?>) o;
return targetType.equals(that.targetType);
}
@Override
public int hashCode() {
return Objects.hash(targetType);
}
}Problem solving: Custom feignFallback exception handling:
1. Custom Exception Handling InvoiceApiFeignFallbackFactory
package com.ruicar.afs.cloud.invoice.factory;
import com.ruicar.afs.cloud.invoice.fallback.InvoiceApiFeignFallback;
import com.ruicar.afs.cloud.invoice.feign.InvoiceApiFeign;
import feign.hystrix.FallbackFactory;
import org.springframework.stereotype.Component;
@Component
public class InvoiceApiFeignFallbackFactory implements FallbackFactory<InvoiceApiFeign> {
@Override
public InvoiceApiFeign create(Throwable throwable) {
InvoiceApiFeignFallback invoiceApiFeignFallback = new InvoiceApiFeignFallback();
invoiceApiFeignFallback.setCause(throwable);
return invoiceApiFeignFallback;
}
}2. feign calls InvoiceApiFeignFallbackFactory
package com.ruicar.afs.cloud.invoice.feign;
import com.alibaba.fastjson.JSONObject;
import com.ruicar.afs.cloud.common.core.feign.annotations.AfsFeignClear;
import com.ruicar.afs.cloud.invoice.dto.InvoiceCheckDto;
import com.ruicar.afs.cloud.invoice.factory.InvoiceApiFeignFallbackFactory;
import io.swagger.annotations.ApiOperation;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestHeader;
import java.util.Map;
/**
* @description: Invoice verification interface
* @author: rongji.zhang
* @date: 2020/8/14 10:32
*/
@FeignClient(name = "invoice", url = "${com.greatwall.systems.invoice-system.url}" ,fallbackFactory = InvoiceApiFeignFallbackFactory.class)
public interface InvoiceApiFeign {
/**
*
* @param dto
* @return
*/
@ApiOperation(" Get business data API Interface ")
@PostMapping(value = "/vi/check")
@AfsFeignClear(true)// Prevent adding internal through this annotation token
JSONObject InvoiceCheck(@RequestBody InvoiceCheckDto dto, @RequestHeader Map<String, String> headers);
}3. Implement custom error reporting
package com.ruicar.afs.cloud.invoice.fallback;
import com.alibaba.fastjson.JSONObject;
import com.ruicar.afs.cloud.invoice.dto.InvoiceCheckDto;
import com.ruicar.afs.cloud.invoice.feign.InvoiceApiFeign;
import lombok.Setter;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import java.util.Map;
/**
* @author Fzero
* @date 2019-01-24
*/
@Slf4j
@Component
public class InvoiceApiFeignFallback implements InvoiceApiFeign {
@Setter
private Throwable cause;
/**
* @param dto
* @param headers
* @return
*/
@Override
public JSONObject InvoiceCheck(InvoiceCheckDto dto, Map<String, String> headers) {
log.error("feign Interface call failed ", cause);
return null;
}
}Feign Remote Call Failed--Lost Request Header
@FeignClient("guli-cart")
public interface CartFenignService {
@GetMapping("/currentUserCartItems")
List<OrderItemVo> getCurrentUserCartItems();
}// When the interface is removed in this way, it is actually Feign At the bottom is 1 A brand new requst All request headers are gone
The solution is to use Feign to remotely deactivate the interceptor, and create the interceptor first in the remote request
@Bean("requestInterceptor")
public RequestInterceptor requestInterceptor() {
return new RequestInterceptor() {
@Override
public void apply(RequestTemplate template) {
/**
* Put the previous one Cookie Put it in the new request The principle is to use the same 1 Thread data sharing ThreadLocal
*/
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletRequest request = attributes.getRequest();
String cookie = request.getHeader("Cookie");
template.header("Cookie", cookie);
}
};
}However, the above method can only solve the problem of agreeing to threads, and the request header will still be lost under multiple threads
Solution under multithreading:
RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();Take out the request separately and give it to each thread separately
RequestContextHolder.setRequestAttributes(requestAttributes);That's it ~