Remove Transfer-Encoding:chunked in the POST request?

Question

I am sending a POST request using the following code but the request is send in the form of chunked (Transfer-Encoding: chunked). I googled about the problem and it says to include the Content-Length but in the below code I could not figure out how could I set the Content-Length:

@RequestMapping(value = "/contacts", method = RequestMethod.POST)
public Map<String, ContactInfo> addContactInfo(
                                @RequestBody Map<String, ContactInfo> ContactInfoDto) {

    ContactInfo contactInfo = ContactInfoDto.get("contact");
    if (contactInfo == null) {
        throw new IllegalArgumentException("Contact not found.");
    }

    contactInfo = this.contactInfoManager.addNew(contactInfo);
    Map<String, ContactInfo> map = new HashMap<>();
    map.put("contact", contactInfo);

    return map;

}

Answer 1

You can use ResponseEntity to set headers explicitly. The tricky bit is figuring out how long your content actually is:

@RequestMapping(value = "/contacts", method = RequestMethod.POST)
public ResponseEntity<Map<String, ContactInfo>> addContactInfo(@RequestBody Map<String, ContactInfo> contactInfoDto) throws JsonProcessingException {

    ContactInfo contactInfo = contactInfoDto.get("contact");
    if (contactInfo == null) {
        throw new IllegalArgumentException("Contact not found.");
    }

    contactInfo = this.contactInfoManager.addNew(contactInfo);
    Map<String, ContactInfo> map = new HashMap<>();
    map.put("contact", contactInfo);

    HttpHeaders headers = new HttpHeaders();
    headers.set(HttpHeaders.CONTENT_LENGTH, String.valueOf(new ObjectMapper().writeValueAsString(map).length()));
    return new ResponseEntity<Map<String, ContactInfo>>(map, headers, HttpStatus.CREATED);
}

Test:

$ curl -v http://localhost:8080/contacts/ -X POST -d '{ "contact": { "name": "foo" } }' -H 'Content-Type: application/json' && echo
*   Trying ::1...
* Connected to localhost (::1) port 8080 (#0)
> POST /contacts/ HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.43.0
> Accept: */*
> Content-Type: application/json
> Content-Length: 32
> 
* upload completely sent off: 32 out of 32 bytes
< HTTP/1.1 201 Created
< Server: Apache-Coyote/1.1
< X-Application-Context: application
< Content-Type: application/json;charset=UTF-8
< Content-Length: 26
< Date: Fri, 10 Jun 2016 13:24:23 GMT
< 
* Connection #0 to host localhost left intact
{"contact":{"name":"foo"}}

Answer 2

The following code:

@RequestMapping(value = "/contacts", method = RequestMethod.POST)
public Map<String, ContactInfo> addContactInfo(
                                @RequestBody Map<String, ContactInfo> ContactInfoDto,    
                                @RequestHeader(value = HttpHeaders.CONTENT_LENGTH, required = true) Long contentLength
) { ... }

Can be used to require Content-Length header to be sent. Just note that you also have to add that header in code that sends request (most of the clients do that automatically but better check)