Sending Gzip compressed data with Spring Android R

Question

The current Spring Android documentation says in section 2.2.2:

RestTemplate supports sending and receiving data encoded with gzip compression.

However, this document explains in section 2.7.2 how to receive Gzip data, but there is nothing about sending gzip data (using a POST or a PUT). Is it a missing feature so the introduction would be erroneous? Or is there some secret way to enable gzip compression?

Answer 1

Just to share my working code for RestTemplate request with AcceptEncoding:gzip

RestTemplate restTemplate = new RestTemplate();  
HttpHeaders requestHeaders = new HttpHeaders();  
requestHeaders.setAcceptEncoding(ContentCodingType.GZIP); 
HttpEntity<Coordinates> requestEntity = new HttpEntity<Coordinates>(coordinates, requestHeaders); 
ResponseEntity<Integer> responseEntity = restTemplate.exchange(url, HttpMethod.PUT, requestEntity, Integer.class);

The source code in answer of @Stoozi not work for me (if you use it simple will not receive compressed response) I have test it with SoapUI

Request:

GET http://localhost:8081/jaxrs/admin-adblock
Accept:application/json
Cache-Control:no-cache
Content-Type:application/json
Authorization:Basic c21h... 
Accept-Encoding:gzip,deflate

Response:

HTTP/1.1 200 OK
Content-Type: application/json
Vary: Accept-Encoding
Content-Encoding: gzip
Content-Length: 204
Server: Jetty(9.2.2.v20140723)

its need to use setAcceptEncoding() instead of setContentEncoding() in RestTemplate REQUEST headers.

Answer 2

GZip compression on requests is based on the "Content-Encoding" header of the request being handled by the RestTemplate. Setting this header to "gzip" will enable Gzip compression for your request. Luckily there are some constants and helper functions available to make this easy:

HttpHeaders headers = new HttpHeaders();
headers.setContentEncoding(ContentCodingType.GZIP);
//...then use headers when making request with RestTemplate instance

Be wary when using a ClientHttpRequestInterceptor with Gzip compression enabled as this will compress your request body multiple times (depending on how many interceptors you have configured) as I describe here: RestTemplate with ClientHttpRequestInterceptor causes GZIP compression twice