The log contains Chinese, which is not displayed correctly.

Description

When print Chinese in Spring Boot projects, then looks like not right, for example:

{"code":45,"name":"广西壮族自治区"}

Expected Behavior

Print Chinese normal, like this:

{"code":45,"name":"广西壮族自治区"}

Actual Behavior

{"code":45,"name":"广西壮族自治区"}

Possible Fix

Must force set utf-8 encoding

server:
  servlet:
    encoding:
      enabled: true
      charset: UTF-8
      force: true

The root cause of this problem

The priority order for specifying the response body is:

1. explicitly per request using setCharacterEncoding and setContentType
2. implicitly per request using setLocale
3. per web application via the deployment descriptor or ServletContext.setRequestCharacterEncoding(String)
4. container default via vendor specific configuration
5. ISO-8859-1

If any possible, get encoding form somewhere else.

Your Environment

• Version used: org.zalando:logbook-spring-boot-starter:2.3.0 & Spring Boot Ver: 2.3.4.RELEASE

[sohtsuka]

@whiskeysierra Is it possible to reconsider the fix? As @kyle18th commented, Spring Boot does not provide the (legal) way to set the response charset when the content type is application/json.

This controller:

@RestController
public class Controller {
    @GetMapping(produces = MediaType.APPLICATION_JSON_VALUE)
    public List<String> demo() {
	// "world" in Chinese characters: https://en.wiktionary.org/wiki/%E4%B8%96%E7%95%8C
	return List.of("世界");
    }
}

produces the UTF-8 JSON response below. It works without setting the response charset.

["世界"]

However, in the Logbook’s log message, the response body is garbled.

2021-07-21 19:38:59.398 TRACE 11671 --- [nio-8080-exec-1] org.zalando.logbook.Logbook              : {"origin":"local","type":"response","correlation":"ce55b6230e12728d","duration":437,"protocol":"HTTP/1.1","status":200,"headers":{"Connection":["keep-alive"],"Content-Type":["application/json"],"Date":["Wed, 21 Jul 2021 19:38:59 GMT"],"Keep-Alive":["timeout=60"],"Transfer-Encoding":["chunked"]},"body":["ããã«ã¡ã¯"]}

This seems to be because Logbook uses the fallback encoding (ISO-8859-1) even if the document is JSON.

Setting the response character encoding explictly:

@GetMapping(produces = MediaType.APPLICATION_JSON_UTF8_VALUE)

fixes the log message.

2021-07-21 19:59:25.295 TRACE 12606 --- [nio-8080-exec-4] org.zalando.logbook.Logbook              : {"origin":"local","type":"response","correlation":"ac7dc50a7cf0fcd0","duration":5,"protocol":"HTTP/1.1","status":200,"headers":{"Connection":["keep-alive"],"Content-Type":["application/json;charset=UTF-8"],"Date":["Wed, 21 Jul 2021 19:59:25 GMT"],"Keep-Alive":["timeout=60"],"Transfer-Encoding":["chunked"]},"body":["世界"]}

But APPLICATION_JSON_UTF8_VALUE is deprecated and should not be used.

[kmaster]

set the response encoding in the previous filter:

response.setCharacterEncoding(“utf-8”);