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How to handle set-cookie Header in SignalR java Client?

I am using SignalR java client in android and .net core3 as my webservice.
I configured a set-cookie header in my responses from webservice to prevent DDOS attacks , but now I can't connect to my Hub because there is no option in SignalR java client to Handle set-cookie header .
How can I fix this problem?

Well after alot of search I came to this :
hubConnection = HubConnectionBuilder.create(HUB_URL).withHandshakeResponseTimeout(60000).withHeaders(mapHeader).setHttpClientBuilderCallback(param1 -> {
param1.addInterceptor(new ApiClient.ReceivedCookiesInterceptor(G.context));
param1.addInterceptor(new ApiClient.AddCookiesInterceptor(G.context));
}).withTransport(TransportEnum.ALL).withAccessTokenProvider(Single.defer(() -> Single.just("An Access Token"))).build();
(setHttpClientBuilderCallback) will give me a configuration builder which I can use to handle setcookie from response .
this is my ReceivedCookiesInterceptor:
public static class ReceivedCookiesInterceptor implements Interceptor {
private Context context;
public ReceivedCookiesInterceptor(Context context) {
this.context = context;
}
#Override
public Response intercept(Chain chain) throws IOException {
Response originalResponse = chain.proceed(chain.request());
if (!originalResponse.headers("Set-Cookie").isEmpty()) {
Log.i("HubLogin", "intercept: "+originalResponse.headers("Set-Cookie"));
HashSet<String> cookies = (HashSet<String>) PreferenceManager.getDefaultSharedPreferences(context).getStringSet("PREF_COOKIES", new HashSet<String>());
for (String header : originalResponse.headers("Set-Cookie")) {
cookies.add(header);
}
SharedPreferences.Editor memes = PreferenceManager.getDefaultSharedPreferences(context).edit();
memes.putStringSet("PREF_COOKIES", cookies).apply();
memes.apply();
}
return originalResponse;
}
}
and this is my AddCookiesInterceptor:
public static class AddCookiesInterceptor implements Interceptor {
public static final String PREF_COOKIES = "PREF_COOKIES";
private Context context;
public AddCookiesInterceptor(Context context ) {
this.context = context;
}
#Override
public Response intercept(Interceptor.Chain chain) throws IOException {
Request.Builder builder = chain.request().newBuilder();
HashSet<String> preferences = (HashSet<String>) PreferenceManager.getDefaultSharedPreferences(context).getStringSet(PREF_COOKIES, new HashSet<>());
for (String cookie : preferences) {
builder.addHeader("Cookie", cookie);
}
return chain.proceed(builder.build());
}
}

How to implement custom error handling with retroift2

I calling to the api with the basic retrofit Call object:
public interface dataApi {
#GET("animal/cats")
Call<AllAnimals> getAllData(
#Query("api_key") String apiKey
);
}
And I can get the response inside my view model like this:
call.enqueue(new Callback<AllAnimals>() {
#Override
public void onResponse(Call<AllAnimals> call, Response<AllAnimals> response) {
animals.setValue(response.body());
}
#Override
public void onFailure(Call<AllAnimals> call, Throwable t) {
Log.i(TAG, "onFailure: " + t);
}
});
Nothing speical here.
I've several problem with this approach
FIRST - if I give the wrong api key for example, the response should give me a response with the code of the problem, instead I just get null body.
SECOND I am planning to have more api calls, and it's a huge code duplication to handle errors every call I wrote.
How can I implement custom error handling for this situation, that will be apply to other calls too?

I think you can use okhttp interceptor and define yourself ResponseBody converter to fix your problem.
First,intercept you interested request and response;
Second,check the response,if response is failed then modify the response body to empty。
define a simple interceptor
Interceptor interceptor = new Interceptor() {
#Override
public okhttp3.Response intercept(Chain chain) throws IOException {
Request request = chain.request();
String url = request.url().toString();
System.out.println(request.url());
okhttp3.Response response = chain.proceed(request);
if (!response.isSuccessful() && url.contains("animal/cats")) {
// request failed begin to modify response body
response = response.newBuilder()
.body(ResponseBody.create(MediaType.parse("application/json"), new byte[] {}))
.build();
}
return response;
}
};
define self ResponseBody converter
most code from com.squareup.retrofit2:converter-jackson we just add two lines:
final class JacksonResponseBodyConverter<T> implements Converter<ResponseBody, T> {
private final ObjectReader adapter;
JacksonResponseBodyConverter(ObjectReader adapter) {
this.adapter = adapter;
}
#Override public T convert(ResponseBody value) throws IOException {
try {
if (value.contentLength() == 0) {
return null;
}
return adapter.readValue(value.charStream());
} finally {
value.close();
}
}
}
the below code is added：
if (value.contentLength() == 0) {
return null;
}

How to reset/remove/clear the request body in rest-assured

I have to pass form-parameter as the body to my request. When I try
Response post = request.urlEncodingEnabled(true).log().all().config(RestAssured.config()
.encoderConfig(EncoderConfig.encoderConfig()
.encodeContentTypeAs("x-www-form-urlencoded", ContentType.URLENC)))
I am getting the error message as "You can either send form parameters OR body content in POST, not both!"
When I checked the log, previous api's response passed as body to this request. How to remove/reset/clear the body and pass only the form-parameter.

You should always use a new RequestSpecification Instance for each request.
Before each new request call a function like:
public void beforeNewRequest(){
restUtils.resetRestAssured(); //reset existing instance
restUtils = RestUtils.getInstance(); //get new instance
}
RestUtil.java class
public class RestUtils {
private static RestUtils apiUtilsInstance = null;
private RequestSpecification httpRequest;
private RestUtils() {
httpRequest = RestAssured.given();
}
public static RestUtils getInstance() {
if (apiUtilsInstance == null)
apiUtilsInstance = new RestUtils();
return apiUtilsInstance;
}
public RequestSpecification getRequestSpecification() {
return httpRequest;
}
public void resetRestAssured() {
apiUtilsInstance = null;
}
}

Feign Client Error Handling - Suppress the Error/Exception and convert to 200 success response

I am using feign client to connect to downstream service.
I got a requirement that when one of the downstream service endpoint returns 400 ( it's partial success scenario ) our service need this to be converted to 200 success with the response value.
I am looking for a best way of doing this.
We are using error decoder to handle the errors and the above conversion is applicable for only one endpoint not for all the downstream endpoints and noticed that decode() method should returns exception back.

You will need to create a customized Client to intercept the Response early enough to change the response status and not invoke the ErrorDecoder. The simplest approach is to create a wrapper on an existing client and create a new Response with a 200 status. Here is an example when using Feign's ApacheHttpClient:
public class ClientWrapper extends ApacheHttpClient {
private ApacheHttpClient delegate;
public ClientWrapper(ApacheHttpClient client) {
this.client = client;
}
#Override
public Response execute(Request request, Request.Options options) throws IOException {
/* execute the request on the delegate */
Response response = this.client.execute(request, options);
/* check the response code and change */
if (response.status() == 400) {
response = Response.builder(response).status(200).build();
}
return response;
}
}
This customized client can be used on any Feign client you need.

Another way of doing is by throwing custom exception at error decoder and convert this custom exception to success at spring global exception handler (using #RestControllerAdvice )
public class CustomErrorDecoder implements ErrorDecoder {
#Override
public Exception decode(String methodKey, Response response) {
if (response.status() == 400 && response.request().url().contains("/wanttocovert400to200/clientendpoints") {
ResponseData responseData;
ObjectMapper mapper = new ObjectMapper();
try {
responseData = mapper.readValue(response.body().asInputStream(), ResponseData.class);
} catch (Exception e) {
responseData = new ResponseData();
}
return new PartialSuccessException(responseData);
}
return FeignException.errorStatus(methodKey, response);
}}
And the Exception handler as below
#RestControllerAdvice
public class GlobalControllerExceptionHandler {
#ResponseStatus(HttpStatus.OK)
#ExceptionHandler(PartialSuccessException.class)
public ResponseData handlePartialSuccessException(
PartialSuccessException ex) {
return ex.getResponseData();
}
}

Change the microservice response:
public class CustomFeignClient extends Client.Default {
public CustomFeignClient(
final SSLSocketFactory sslContextFactory, final HostnameVerifier
hostnameVerifier) {
super(sslContextFactory, hostnameVerifier);
}
#Override
public Response execute(final Request request, final Request.Options
options) throws IOException {
Response response = super.execute(request, options);
if (HttpStatus.SC_OK != response.status()) {
response =
Response.builder()
.status(HttpStatus.SC_OK)
.body(InputStream.nullInputStream(), 0)
.headers(response.headers())
.request(response.request())
.build();
}
return response;
}
}
Add a Feign Client Config:
#Configuration
public class FeignClientConfig {
#Bean
public Client client() {
return new CustomFeignClient(null, null);
}
}

Send HTTP GET request with header

From my Android app I want to request a URL with GET parameters and read the response.
In the request I must add a x-zip header.
The URL is something like
http://example.com/getmethod.aspx?id=111&method=Test
Can some one provide me code for that?
Two things are important: that it is a GET request and contains the x-zip header .
EDIT:
try {
HttpClient client = new DefaultHttpClient();
String getURL = "http://example.com/getmethod.aspx?id=111&method=Test";
HttpGet get = new HttpGet(getURL);
get.setHeader("Content-Type", "application/x-zip");
HttpResponse responseGet = client.execute(get);
HttpEntity resEntityGet = responseGet.getEntity();
if (resEntityGet != null) {
//do something with the response
Log.i("GET ",EntityUtils.toString(resEntityGet));
}
} catch (Exception e) {
e.printStackTrace();
}
I try with this code but I get code with .net error: Object reference not set to an instance of an object...
I think but I'm not sure this if for x-zip header, is header in my code ok?

Here's a code excerpt we're using in our app to set request headers. You'll note we set the CONTENT_TYPE header only on a POST or PUT, but the general method of adding headers (via a request interceptor) is used for GET as well.
/**
* HTTP request types
*/
public static final int POST_TYPE = 1;
public static final int GET_TYPE = 2;
public static final int PUT_TYPE = 3;
public static final int DELETE_TYPE = 4;
/**
* HTTP request header constants
*/
public static final String CONTENT_TYPE = "Content-Type";
public static final String ACCEPT_ENCODING = "Accept-Encoding";
public static final String CONTENT_ENCODING = "Content-Encoding";
public static final String ENCODING_GZIP = "gzip";
public static final String MIME_FORM_ENCODED = "application/x-www-form-urlencoded";
public static final String MIME_TEXT_PLAIN = "text/plain";
private InputStream performRequest(final String contentType, final String url, final String user, final String pass,
final Map<String, String> headers, final Map<String, String> params, final int requestType)
throws IOException {
DefaultHttpClient client = HTTPClientFactory.newClient();
client.getParams().setParameter(HttpProtocolParams.USER_AGENT, mUserAgent);
// add user and pass to client credentials if present
if ((user != null) && (pass != null)) {
client.getCredentialsProvider().setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(user, pass));
}
// process headers using request interceptor
final Map<String, String> sendHeaders = new HashMap<String, String>();
if ((headers != null) && (headers.size() > 0)) {
sendHeaders.putAll(headers);
}
if (requestType == HTTPRequestHelper.POST_TYPE || requestType == HTTPRequestHelper.PUT_TYPE ) {
sendHeaders.put(HTTPRequestHelper.CONTENT_TYPE, contentType);
}
// request gzip encoding for response
sendHeaders.put(HTTPRequestHelper.ACCEPT_ENCODING, HTTPRequestHelper.ENCODING_GZIP);
if (sendHeaders.size() > 0) {
client.addRequestInterceptor(new HttpRequestInterceptor() {
public void process(final HttpRequest request, final HttpContext context) throws HttpException,
IOException {
for (String key : sendHeaders.keySet()) {
if (!request.containsHeader(key)) {
request.addHeader(key, sendHeaders.get(key));
}
}
}
});
}
//.... code omitted ....//
}

You do it exactly as you showed with this line:
get.setHeader("Content-Type", "application/x-zip");
So your header is fine and the problem is some other input to the web service. You'll want to debug that on the server side.