How to log json response in Spring Boot?-CodePudding

If I define a response entity class and return it by my rest controller, controller will change this class to json string. I want to log this json string, how to do it? Thanks.

For example:

Response entity class:

@Data
@AllArgsConstructor
public class ResponseEntity {
    String code;
    String message;
}

Rest Controller:

@RestController
@RequestMapping("/")
public class StudentController {
    @RequestMapping("test")
    public ResponseEntity test(){
        return new ResponseEntity(200,"success");
    }
}

I want to record this json response in log

{"code":200,"message":"success"}

CodePudding user response：

The simplest and handy way is convert it to JSON string manually and then log it. You can convert it to JSON by ObjectMapper.

@Log4j2
@RequestMapping("/")
public class StudentController {

    @Autowired
    private ObjectMapper objectMapper;

    @RequestMapping("test")
    public ResponseEntity test() throws Exception {
        ResponseEntity entity = new ResponseEntity(200, "success");
        log.debug("{}", objectMapper.writeValueAsString(entity));
        return entity;
    }
}

Or you can use Logstash json_event pattern for log4j if you need advanced feature.

CodePudding user response：

In order to accomplish you desired behaviour the spring framework offers an utility class which does exactly the requested job for your.

Just declare this:

@Configuration
public class RequestLoggingFilterConfig {

@Bean
public CommonsRequestLoggingFilter logFilter() {
    CommonsRequestLoggingFilter filter
      = new CommonsRequestLoggingFilter();
    filter.setIncludeQueryString(true);
    filter.setIncludePayload(true);
    filter.setMaxPayloadLength(10000);
    filter.setIncludeHeaders(false);
    filter.setAfterMessagePrefix("REQUEST DATA : ");
    return filter;
}
}

And add to your logging file this appender:

<logger name="org.springframework.web.filter.CommonsRequestLoggingFilter">
<level value="DEBUG" />
</logger>

Same result can be done with this application.properties property

logging.level.org.springframework.web.filter.CommonsRequestLoggingFilter=DEBUG

this should be enough, but, in case you want a fine grained control on the logging operation you can create your own filter by extending AbstractRequestLoggingFilter .