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How to send Gzip Request using RestTemplate?

I have the following code with large pojo (MyRequest) which I wanted to send in Gzip, but it's unable to hit the end-point that accept Gzip request. Am I creating Gzip request correctly? Do I need to send the pojo as a file?
MyRequest request = new MyRequest ();
HttpHeaders httpHeaders = HttpHeaders();
httpHeaders.add(HttpHeaders.CONTENT_ENCODING, "gzip");
httpHeaders.add(HttpHeaders.ACCEPT_ENCODING, "gzip");
httpHeaders.add(HttpHeaders.CONTENT_TYPE, "gzip");
HttpEntity<byte[]> entity = new HttpEntity<>(compress(request), headers);
ResponseEntity<MyResponse> response = restTemplate.postForEntity(url, entity, MyResponse.class);
public static Byte[] compress(byte[] body) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
try (GZIPOutputStream gzipOutputStream = new GZIPOutputStream(baos)) {
gzipOutputStream.write(body);
}
return baos.toByteArray();
}
Kindly share an example of Gzip encoding using RestTemplate, thanks

accept-encoding: gzip, deflate, br
Is for http clients to make requests to a server and expect an http response that is:
content-encoding: gzip
To what you are doing see this answer: https://serverfault.com/a/56707

Getting 403 error during GET request from Java application

I am trying to do a GET request with JAVA client using RestTemplate library, resulting in following error:
Exception in thread "main" org.springframework.web.client.HttpClientErrorException$Forbidden: 403 Forbidden
When I am trying to hit the same URL by command line it is working fine. Posting the cURL command and Java code snippet here.
cURL :
curl -X GET -H "Authorization: Bearer ${TOKEN}" -H "Content-Type: application/json" https://xxxx-xxxx-xxxx {"key":"value"}
JAVA snippet :
String URL="https://xyz";
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
//setting up the required headers
headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
headers.set("Authorization", "Bearer "+accessToken);
HttpEntity<String> entity = new HttpEntity<String>("body",headers);
//get request
ResponseEntity<String> responseEntity = restTemplate.exchange(URL, HttpMethod.GET, entity, String.class);
P.S - Is the issue because of the URL being a HTTPS one instead of HTTP ?

Add the user agent header, try and let us know if it works.
String URL="https://xyz";
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
//setting up the required headers
headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
//settting user agent
headers.add("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36");
headers.set("Authorization", "Bearer "+accessToken);
HttpEntity<String> entity = new HttpEntity<String>("body",headers);
//get request
ResponseEntity<String> responseEntity = restTemplate.exchange(URL, HttpMethod.GET, entity, String.class);

Prevent Spring's RestTemplate from adding header for each parameters in multipart/form-data

I have to use Spring's RestTemplate to call an external API that takes a POST request with Content-Type: multipart/form-data. The input data are only key-values, no attachments but the server enforce me the use multipart/form-data.
Following is the raw request that works fine.
POST http://the-api:8080 HTTP/1.1
Content-Type: multipart/form-data; boundary=--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Accept: */*
Host: the-api:8080
accept-encoding: gzip, deflate
content-length: 680
Connection: keep-alive
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Content-Disposition: form-data; name="param1"
value1
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Content-Disposition: form-data; name="param2"
value2
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL--
Following is the raw request that I extracted and rearranged from the log of the RestTemplate, it did not work because the server mistook the header for the value.
POST http://the-api:8080 HTTP/1.1
Content-Type: multipart/form-data; boundary=--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Accept: */*
Host: the-api:8080
accept-encoding: gzip, deflate
content-length: 680
Connection: keep-alive
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Content-Disposition: form-data; name="param1"
Content-Type: text/plain;charset=UTF-8
Content-Length: 29
value1
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL
Content-Disposition: form-data; name="param2"
Content-Type: text/plain;charset=UTF-8
Content-Length: 14
value2
--Eh0oKOHPOSEIJTzFevDxHhPNKhQl7AP6kQL--
Following is the code
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);
MultiValueMap<String, String> params = new LinkedMultiValueMap<>();
params.add("param1", "value1);
params.add("param2", "value2);
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<>(params, headers);
URI uri = UriComponentsBuilder.fromHttpUrl("http://the-api:8080")
.build().encode(Charset.forName("UTF-8")).toUri();
return restTemplate.postForObject(uri, request, KKPMailResponse.class);
Question
How to prevent Spring's RestTemplate from automatically add the header Content-Type: text/plain;charset=UTF-8 and Content-Length: xx for each parameters

I didn't find a way to prevent Spring from generating the entries, but you can use an interceptor to remove them before sending the request. For that you have to manipulate the request body in the interceptor as follows:
public class MultiPartFormDataCleaningInterceptor implements ClientHttpRequestInterceptor {
#Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
final MediaType contentType = request.getHeaders().getContentType();
if (contentType != null
&& MediaType.MULTIPART_FORM_DATA.getType().equals(contentType.getType())
&& MediaType.MULTIPART_FORM_DATA.getSubtype().equals(contentType.getSubtype())) {
return execution.execute(request, stripContentTypeAndLength(body));
}
return execution.execute(request, body);
}
private byte[] stripContentTypeAndLength(byte[] body) {
final String bodyStr = new String(body);
final StringBuilder builder = new StringBuilder();
try (final Scanner scanner = new Scanner(bodyStr)) {
while (scanner.hasNextLine()) {
final String line = scanner.nextLine();
if (!line.startsWith("Content-Type:")
&& !line.startsWith("Content-Length:")) {
builder.append(line).append("\r\n");
}
}
}
final String newBodyStr = builder.toString();
return newBodyStr.getBytes();
}
}

If think you can use ClientHttpRequestInterceptor to remove headers:
public class SomeHttpRequestInterceptor implements ClientHttpRequestInterceptor
{
#Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException
{
HttpHeaders headers = request.getHeaders();
headers.remove("your header 1);
headers.remove("your header 2);
return execution.execute(request, body);
}
}
And set it in RestTemplate in this way:
RestTemplate restTemplate = new RestTemplate();
List<ClientHttpRequestInterceptor> interceptors = Arrays.asList(new CustomHttpRequestInterceptor())
restTemplate.setInterceptors(interceptors);

Can get response from browser, but 401 unauthorized from resttemplate

Can get from the response from Chrome, but when I want to get it with resttemplate it gives me 401 response.
I try to add the exact Content Types with rest template but it still gives the 401 error.
here is the request that i get it from Chrome :
GET URL HTTP/1.1
Host: host
Connection: keep-alive
Cache-Control: max-age=0
Authorization: Basic auth
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
Accept-Encoding: gzip, deflate, br
Accept-Language: en,de;q=0.9,tr;q=0.8
and here is the code that i used in java to connect the service :
RestTemplate restTemplate = new RestTemplate();
List<HttpMessageConverter<?>> messageConverters = new ArrayList<>();
MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
converter.setSupportedMediaTypes(Arrays.asList(MediaType.APPLICATION_XHTML_XML, MediaType.APPLICATION_XML, MediaType.TEXT_HTML));
messageConverters.add(converter);
restTemplate.setMessageConverters(messageConverters);
HttpEntity<Map<String, String>> entity = new HttpEntity<>(params,createHeaders(username, password));
restTemplate.getForObject("URL",String.class, entity);
public static HttpHeaders createHeaders(String username, String password) {
String auth = username + ":" + password;
byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(Charset.forName("US-ASCII")));
String authHeader = "Basic " + new String(encodedAuth);
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.set("Authorization", authHeader);
return httpHeaders;
}

It appears to be a problem with encoding the authorization token generation.
If you are sure about the username and password is correct, the only possibility is that the method/encoding used to generate the token is different on the browser(or the UI application which is generating the token) and the implementation of your createHeaders() method.
Please refer to the below links for more details:
What encoding should I use for HTTP Basic Authentication?
https://github.com/request/request/issues/1334
Hope it'll help.

Spring - changing Content-type HTTP header

I am communicating with a JSON API using Robospice. This is how I set the headers for a POST request:
mHttpHeaders = new HttpHeaders();
mHttpHeaders.add("Content-Type", "application/json");
Log.d(Global.TAG, mHttpHeaders.toString());
The problem is that I get a header which looks like that: {Content-Type=[application/json]} where I need to send Content-Type:application/json (which seems to be the only header that my server accepts). I can't find any way to change it (tried with both add() and setContentType() methods), how do I do that?

You should try followings and it works for me. I'm using Spring rest template inside Robospice.
MediaType mediaType = new MediaType("application", "json");
List<MediaType> acceptableMediaTypes = new ArrayList<MediaType>();
acceptableMediaTypes.add(mediaType);
HttpHeaders headers = new HttpHeaders();
headers.setAccept(acceptableMediaTypes);

The output
{Content-Type=[application/json]}
you see in the Log statement is just the String returned by the toString() method, it's not the actual header sent. For example
public static void main(String[] args) throws Exception {
HttpHeaders headers = new HttpHeaders();
headers.add("Content-Type", "application/json");
System.out.println(headers);
}
prints
{Content-Type=[application/json]}
If you are using the HttpClient and HttpRequestBase (HttpGet, HttpPost, etc.) correctly, the header will be sent just fine.