One of token passing between microservices @feign's token passing

Method 1 ,@RequestHeader

Add... To the microservice method header of the request caller @RequestHeader Used to receive incoming requests from the client token, Key code snippets

@GetMapping(value = "/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
public ShareDTO findById(HttpServletRequest request,
                         @PathVariable Integer id,
                         @RequestParam(name = "foo") String foo,
                         @RequestHeader("X-Token") String token) {
    System.out.println(foo);
    return this.shareService.findById(id, token);
}

Here we get header Medium “X-Token”

When using Feign Obtained when calling other microservices Token It is passed into the request header of the next microservice

@GetMapping("/users/{id}")
UserDTO findById(@PathVariable Integer id, @RequestHeader("X-Token") String token);

there @RequestHeader It means that the parameter token Put in the request header of the next request header in . Here we are , Use this way to token Transfer can be realized .

Method 2 Use Feign Of Interceptor

Step1 Realization RequestInterceptor Interface

apply-> Get X-Token

Step2 take token Pass on to the next request

Achieve one RequestInterceptor

The implementation is as follows

// Omit package name 
import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.apache.commons.lang3.StringUtils;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;

/**
 * @author frend
 * @version v0.0.1
 * @apiNote feign Pass on token Intercept for unified processing 
 * @time 2020/10/26 12:48
 * @parjectName rate-content-center
 */
public class TokenTelayRequestIntecepor implements RequestInterceptor {

    @Override
    public void apply(RequestTemplate requestTemplate) {
        //  from header obtain X-token
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        ServletRequestAttributes srat = (ServletRequestAttributes) requestAttributes;
        HttpServletRequest request = srat.getRequest();
        String token = request.getHeader("X-Token");
        if (StringUtils.isNotBlank(token)) {
            // take token Pass out 
            requestTemplate.header("X-Token", token);
        }
    }
}

Get it here first HTTPServletRequest

Then from request Get to the header Of “X-Token”

Put this token Pass to requestTemplate

Interceptor After the implementation, you need to do some work on this Interceptor Set configuration

Step3 To configure Feign

Configure a global requestInterceptors: Implement the above RequestInterceptor The full path of the class to this configuration

feign:
  client:
    config:
      default:
        loggerLevel: full
        requestInterceptors:
          - org.rate.contentcenter.feignclients.interceptor.TokenTelayRequestIntecepor

Here we are , Overall FeignToken The delivery is complete .

Finally, make a conclusion ：

1. Use @RequestHeader The way is more intuitive , It is also easier to understand , But when the interface is modified , Or when there are too many service interfaces , The task is huge

2. Use RequestInterceptor Interceptor , There are some abstractions in understanding , However, this method has great advantages in actual operation and code coupling .