spring-mvc:chunked responses with status 500 are damaged

version: Spring Boot 2.2.5.RELEASE environment: java: Java™ SE Runtime Environment (build 1.8.0_172-b11) os: mac. os and linux contrainer: tomcat

the bug is related to here I have worked for days to reproduced the problem

https://github.com/spring-cloud/spring-cloud-gateway/issues/1600

when I create a controller and just return ResponseEntity there will be return

curl: (56) Illegal or missing hexadecimal sequence in chunked-encoding

my code

@RequestMapping("api/v1")
@RestController
public class ProxyController {

    @GetMapping("/proxy500")
    public ResponseEntity<?> proxy500(ProxyExchange<byte[]> proxy) {
        MultiValueMap<String, String> multiValueMap = new HttpHeaders();
        multiValueMap.put("Transfer-Encoding", Collections.singletonList("chunked"));
        multiValueMap.put("Connection", Collections.singletonList("close"));
        return new ResponseEntity<>("{", multiValueMap, HttpStatus.INTERNAL_SERVER_ERROR);
    }
}

detail

curl http://localhost:8080/api/v1/proxy500 -vvv
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 8080 (#0)
> GET /api/v1/proxy500 HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.54.0
> Accept: */*
> 
< HTTP/1.1 500 
< Transfer-Encoding: chunked
< Connection: close
< Content-Type: text/plain;charset=UTF-8
< Date: Sat, 14 Mar 2020 17:13:04 GMT
< 
* Illegal or missing hexadecimal sequence in chunked-encoding
* stopped the pause stream!
* Closing connection 0
curl: (56) Illegal or missing hexadecimal sequence in chunked-encoding

reason maybe here , the header info send flush until message send

org.springframework.http.converter.StringHttpMessageConverter#writeInternal

@Override
protected void writeInternal(String str, HttpOutputMessage outputMessage) throws IOException {
    HttpHeaders headers = outputMessage.getHeaders();
    if (this.writeAcceptCharset && headers.get(HttpHeaders.ACCEPT_CHARSET) == null) {
        headers.setAcceptCharset(getAcceptedCharsets());
    }
    Charset charset = getContentTypeCharset(headers.getContentType());
    StreamUtils.copy(str, charset, outputMessage.getBody());
}

this my source code

https://github.com/taojiaenx/spring-chunk-bug.git

[taojiaenx]

@rstoyanchev thx, I am will keep working on it

[jaggerwang]

Same problem! I think it should be solved in application framework not in servlet container.