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Resolve invocation and transfer token between services

Today's microservices are basically authorization and authentication done by SpringSecurity+Oauth3. If multiple services are called directly through Fegin, an error of 401will be reported.

A. The direct call of the service interface with permission handling will cause the unauthorized error of http 401during the call, which will lead to the error of the internal server of http 500of the final service.

B. Solution: the most convenient way is to add token to the request header and bring it together.

Feign provides an interface RequestInterceptor

As long as we implement this interface and do some simple processing, for example, if we verify that the token of the request header is called Access-Token, we will first take out the token of the current request and put it on the feign request header

Public class FeignConfig implements RequestInterceptor {@ Override public void apply (RequestTemplate requestTemplate) {ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes (); HttpServletRequest request = attributes.getRequest (); / / add token requestTemplate.header (HttpHeaders.AUTHORIZATION, request.getHeader (HttpHeaders.AUTHORIZATION)) }} invocation mode @ FeignClient (name = "qtjuaa", configuration = FeignConfig.class) public interface UaaClient {@ RequestMapping (value = "/ api/test", method= RequestMethod.GET) String test ();} Feign invocation service various pit processing to write called service @ RefreshScope@RestControllerpublic class XXXController extends BaseController implements IndicatorsFeignApi {@ Resource private XXXService xxx @ Override public Wrapper getXXXX (@ RequestBody CommonDto commonDto) {try {CommonVo vo = xxx.getdata (commonDto); return WrapMapper.ok (vo);} catch (Exception e) {e.printStackTrace () Return WrapMapper.error ("system exception, please contact the administrator!");} / / Service is not displayed. Note that @ RequestBody should be added when the parameter is passed to the service layer to obtain the parameter.

Add feign-related configuration to the configuration file

Write and call api

Add related dependencies to the pom file

Org.springframework.cloudspring-cloud-starter-hystrixorg.springframework.cloudspring-cloud-starter-netflix-hystrix-dashboard

Call Api

@ FeignClient (value = "called service name") public interface IndicatorsFeignApi {@ PostMapping (value = "/ api/getXXXX", consumes= "application/json", headers = {"Accept=application/json", "Content-Type=application/json"}) Wrapper getXXXX (@ RequestBody CommonDto commonDto);}

Feign calls error handling. If an error occurs, it will jump to fallback processing.

@ Componentpublic class IndicatorsFeignApiHystrix implements IndicatorsFeignApi {@ Override public Wrapper getXXXX (CommonDto commonDto) {System.out.println ("= exception occurred when calling the service to get data ="); return null;}}

When fallback is enabled, some errors will not be printed on the console, so you can modify the

Feign: hystrix: enabled: true

Change enabled to false, and the fallback will not jump after the error occurs.

There is a pit where the service can be successfully invoked at that time, but there is an error:

Could not extract response: no suitable HttpMessageConverter found for response type [XXXX] and content type [text/html;charset=UTF-8]

It seems that the encoding of the returned data is different from that of the receiving entity class, resulting in an error. Add headers = {"Accept=application/json", "Content-Type=application/json"} to solve the problem.

Write the client service / / serviceImp layer @ Autowired private IndicatorsFeignApi api;// declaration to call api @ Override public CommonVo getXXX (CommonDto commonDto) {Wrapper result = api.getXXXX (commonDto); / / Service call if (resultcalling null) {return result.getResult ();} else {return new CommonVo () }} the above is the content of this article on "how to solve the problem of calling and transferring token between services by Feign". I believe everyone has a certain understanding. I hope the content shared by the editor will be helpful to you. If you want to learn more about related knowledge, please follow the industry information channel.

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