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java.i.o.Exception End of stream error while on citrix secure hub as MDX

I saw this question asked so many times but mine is with different case. Please dont mark it as duplicate.
Following is my client for retrofit. Which works perfectly fine when we're using apk. But as soon as we convert it to MDX for citrix/secure hub we are facing this end of stream error.
I have also tried this with volley but am getting same error. As you can see that I have tried all the interceptor and all for retrofit.
Already tried following interceptor.
addHeader("Connection", "close")
retryOnConnectionFailure(true)
So my question is what is happening exactly? Why is it working in apk and not on MDX.
public static Retrofit getClient() {
//Basic Auth
String authToken = null;
if (!TextUtils.isEmpty(AppConfig.username) &&
!TextUtils.isEmpty(AppConfig.password)) {
authToken = Credentials.basic((String) AppConfig.username, (String) AppConfig.password);
}
//Create a new Interceptor.
final String finalAuthToken = authToken;
Interceptor headerAuthorizationInterceptor = new Interceptor() {
#Override
public okhttp3.Response intercept(Chain chain) throws IOException {
okhttp3.Request request = chain.request();
Headers headers = request.headers().newBuilder()
// .add("Authorization", finalAuthToken)
.add("Connection", "close").build();
request = request.newBuilder().headers(headers).build();
return chain.proceed(request);
}
};
//TO be added in milliseconds
List < Protocol > protos = new ArrayList < > ();
protos.add(Protocol.HTTP_2);
protos.add(Protocol.HTTP_1_1);
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(interceptor)
.protocols(protos)
.retryOnConnectionFailure(true) //FIRST TRY : Added this line after getting Unexpected end of stream error.
.connectTimeout(180, TimeUnit.SECONDS)
.readTimeout(180, TimeUnit.SECONDS)
.writeTimeout(180, TimeUnit.SECONDS)
//.addInterceptor(new GzipRequestInterceptor())
// THIRD TRY : Added this new interceptor for end of stream error
/*.addInterceptor(new Interceptor() {
#NonNull
#Override
public Response intercept(#NonNull Chain chain) throws IOException {
Request request = chain.request().newBuilder()
.addHeader("Connection", "close")
.addHeader("Transfer-Encoding", "chunked")
//.addHeader("Accept-Encoding", "gzip")
.build();
return chain.proceed(request);
}
})*/
//.addInterceptor(headerAuthorizationInterceptor) // SECOND TRY : Added this line after getting Unexpected end of stream error. fot connection close
//ABOVE LINE is Next try would be adding this line as
// this headerInterceptor we have added .add("Connection","close")
// may be we need to remove the authorization from that headerInterceptor
.build();
return new Retrofit.Builder()
.addCallAdapterFactory(RxJavaCallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.client(client)
.baseUrl(AppConfig.mainURLDev3forRetrofit2)
.build(); }

Retrofit OKHTTP Offline caching not working

I read dozens of tutorial and Stackoverflow answers to my problem but nothing is working for me! Also, most of them are old so probably OKHTTP changed somehow.
All I want is to enable offline caching for Retrofit.
I am using GET
I tried using only offlineCacheInterceptor as an Interceptor, but I kept getting:
Unable to resolve host "jsonplaceholder.typicode.com": No address associated with hostname
I tried using a combination of offlineCacheInterceptoras an Interceptor + provideCacheInterceptor() as a NetworkInterceptor, but I kept getting:
504 Unsatisfiable Request (only-if-cached) and a null response.body()
I even made sure to add .removeHeader("Pragma") everywhere!
I tried all these Links:
https://newfivefour.com/android-retrofit2-okhttp3-cache-network-request-offline.html (One interceptor, Not working!!)
https://medium.com/mindorks/caching-with-retrofit-store-responses-offline-71439ed32fda (One interceptor, Not working!)
https://caster.io/lessons/retrofit-2-offline-cache (Separate Online + Offline caching, Not working)
https://www.journaldev.com/23297/android-retrofit-okhttp-offline-caching (Not working, 504 Unsatisfiable Request (only-if-cached))
http://mikescamell.com/gotcha-when-offline-caching-with-okhttp3/ (One interceptor, Not working!!)
https://stackoverflow.com/a/48295397/8086424 (Not Working)
Unable to resolve host "jsonplaceholder.typicode.com": No address associated with hostname
Can Retrofit with OKHttp use cache data when offline (TOO confusing!)
Here's my code:
public static Retrofit getRetrofitInstance(Context context) {
if (retrofit == null) {
c = context;
int cacheSize = 10 * 1024 * 1024; // 10 MB
Cache cache = new Cache(context.getCacheDir(), cacheSize);
OkHttpClient okHttpClient = new OkHttpClient.Builder()
.addInterceptor(provideHttpLoggingInterceptor())
.addInterceptor(offlineCacheInterceptor)
.addNetworkInterceptor(provideCacheInterceptor())
.cache(cache)
.build();
//////////////////////////
retrofit = new retrofit2.Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.client(okHttpClient)
.build();
}
return retrofit;
}
public static Interceptor offlineCacheInterceptor = new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
Log.e("bbbb", "bbbb");
if (!checkInternetAvailability()) {
Log.e("aaaaa", "aaaaaa");
CacheControl cacheControl = new CacheControl.Builder()
.maxStale(30, TimeUnit.DAYS)
.build();
request = request.newBuilder()
.cacheControl(cacheControl)
.removeHeader("Pragma")
.build();
}
return chain.proceed(request);
}
};
public static Interceptor provideCacheInterceptor() {
return new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Response response = chain.proceed(chain.request());
// re-write response header to force use of cache
CacheControl cacheControl = new CacheControl.Builder()
.maxAge(2, TimeUnit.MINUTES)
.build();
return response.newBuilder()
.header(CACHE_CONTROL, cacheControl.toString())
.removeHeader("Pragma")
.build();
}
};
}
I am using jsonplaceholder.typicode.com/photos that returns:
content-type: application/json; charset=utf-8
date: Sun, 21 Oct 2018 14:26:41 GMT
set-cookie: __cfduid=d9e935012d2f789245b1e2599a41e47511540132001; expires=Mon, 21-Oct-19 14:26:41 GMT; path=/; domain=.typicode.com; HttpOnly
x-powered-by: Express
vary: Origin, Accept-Encoding
access-control-allow-credentials: true
expires: Sun, 21 Oct 2018 18:26:41 GMT
x-content-type-options: nosniff
etag: W/"105970-HCYFejK2YCxztz8++2rHnutkPOQ"
via: 1.1 vegur
cf-cache-status: REVALIDATED
expect-ct: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
server: cloudflare
cf-ray: 46d466910cab3d77-MXP
Cache-Control: public, max-age=60

June 2021 (Retrofit 2.9.0 or OKHTTP 3.14.9) Complete Solution (Update)
Same approach is still working since: Oct. 2018
Oct. 2018 (Retrofit 2.4 or OKHTTP 3.11) Complete Solution
Ok, so Online & Offline caching using OKHTTP or Retrofit has been causing so many problems for many people on stackoverflow and other forums. There are tons of misleading information and non-working code samples all over the internet.
So, today I will explain how you can implement online & offline caching using Retrofit & OKHTTP with clear steps + How to test and know whether you are getting the data from cache or network.
If you are getting a 504 Unsatisfiable Request (only-if-cached) OR an Unable to resolve host "HOST": No address associated with hostnamethen you can use any of the following solutions.
Before you begin, you must always remember to:
Make sure you are using a GET request and not a POST!
Always make sure you add .removeHeader("Pragma") as shown below (This lets you override the server's caching protocol)
Avoid using the HttpLoggingInterceptor while testing, it can cause some confusion in the beginning. Enable it in the end if you want.
ALWAYS ALWAYS ALWAYS delete your app from the device and reinstall it again upon every change in code, if you want to explore using Interceptors. Otherwise changing code while the old cache data is still on the device will cause you lots of confusion and misleading deductions!
The order of adding Interceptors to OKHTTPClient object matters!
N.B: If you want to depend on your server's caching protocol for online and offline caching, then don't read the 2 solutions. Just read this article. All you need is to create a cache object and attache it to OKHTTPClient object.
Solution 1: (Longer, but you have full control)
Step 1: (Create onlineInterceptor)
static Interceptor onlineInterceptor = new Interceptor() {
#Override
public okhttp3.Response intercept(Chain chain) throws IOException {
okhttp3.Response response = chain.proceed(chain.request());
int maxAge = 60; // read from cache for 60 seconds even if there is internet connection
return response.newBuilder()
.header("Cache-Control", "public, max-age=" + maxAge)
.removeHeader("Pragma")
.build();
}
};
Step 2: (Create Offline Interceptor) (Only if you want cache access when offline)
static Interceptor offlineInterceptor= new Interceptor() {
#Override
public okhttp3.Response intercept(Chain chain) throws IOException {
Request request = chain.request();
if (!isInternetAvailable()) {
int maxStale = 60 * 60 * 24 * 30; // Offline cache available for 30 days
request = request.newBuilder()
.header("Cache-Control", "public, only-if-cached, max-stale=" + maxStale)
.removeHeader("Pragma")
.build();
}
return chain.proceed(request);
}
};
Step 3: (Create a cache object)
int cacheSize = 10 * 1024 * 1024; // 10 MB
Cache cache = new Cache(context.getCacheDir(), cacheSize);
Step 4: (Add interceptors and cache to an OKHTTPClient object)
OkHttpClient okHttpClient = new OkHttpClient.Builder()
// .addInterceptor(provideHttpLoggingInterceptor()) // For HTTP request & Response data logging
.addInterceptor(OFFLINE_INTERCEPTOR)
.addNetworkInterceptor(ONLINE_INTERCEPTOR)
.cache(cache)
.build();
Step 5:(If you are using Retrofit, add the OKHTTPClient object to it)
retrofit = new retrofit2.Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.client(okHttpClient)
.build();
DONE!
Solution 2: (Just use a library to do all that for you! But deal with the limitations)
Use OkCacheControl library
Step 1 (Create Cache object as shown above)
Step 2 (Create an OKHTTPClient object)
OkHttpClient okHttpClient = OkCacheControl.on(new OkHttpClient.Builder())
.overrideServerCachePolicy(1, MINUTES)
.forceCacheWhenOffline(networkMonitor)
.apply() // return to the OkHttpClient.Builder instance
//.addInterceptor(provideHttpLoggingInterceptor())
.cache(cache)
.build();
Step 3:(Attach the OKHTTPClient object to Retrofit as shown above)
Step 4: (Create a NetworkMonitor Object)
static OkCacheControl.NetworkMonitor networkMonitor=new
OkCacheControl.NetworkMonitor() {
#Override
public boolean isOnline() {
return isInternetAvailable();
}
};
DONE!
Testing:
In order to know whether your device is getting data from the network or from cache, simply add the following code to your onResponse method of Retrofit.
public void onResponse(Call<List<RetroPhoto>> call, Response<List<RetroPhoto>> response) {
if (response.raw().cacheResponse() != null) {
Log.e("Network", "response came from cache");
}
if (response.raw().networkResponse() != null) {
Log.e("Network", "response came from server");
}
}
If the device is using the Network, you will get "response came from server".
If device is using Cache, you will get both of the above responses! For more info about this read this article.
For more info about using OKHTTP interceptors go to this page.

How to use cache response for Retrofit with OkHttp when network response returns error

I have a simple use case: Use network response when success. Else use cached response.
But the problem is that when network response is an error, the cache is also written with that response.
One of the suggestions I read is to do FORCE_CACHE in the Interceptor when networkResponse is not successful.
But since the networkResponse overrides cache with error, next time when you request (and the server still returns an error), the cache will have an error.
Below is my current snippet. I need to add logic for returning cached value when networkResponse is an error. Any suggestion will be greatly helpful.
private void setup() {
OkHttpClient.Builder builder = new OkHttpClient.Builder();
builder.addInterceptor(REWRITE_CACHE_CONTROL);
File httpCacheDirectory = new File(context.getCacheDir(), "responses");
Cache cache = new Cache(httpCacheDirectory, 10 * 1024 * 1024); // 10 MB
builder.cache(cache);
}
private static final Interceptor REWRITE_CACHE_CONTROL = new Interceptor() {
#Override
public okhttp3.Response intercept(#NonNull Chain chain) throws IOException {
Request request = chain.request();
if (!hasAConnection()) {
request = request.newBuilder().cacheControl(CacheControl.FORCE_CACHE).build();
}
return chain.proceed(request);
}
};

Retrofit + RxJava fails to cache responses, suspected response headers

I'm trying to configure cache with Retrofit 1.9.0 and OkHtttp 2.5.0.
Here is how I provide OkHttpClient for my RestAdapter:
#Provides
#Singleton
public OkHttpClient provideOkHttpClient() {
OkHttpClient okHttpClient = new OkHttpClient();
okHttpClient.setConnectTimeout(TIMEOUT_IN_SECONDS, TimeUnit.SECONDS);
okHttpClient.setReadTimeout(TIMEOUT_IN_SECONDS, TimeUnit.SECONDS);
okHttpClient.setWriteTimeout(TIMEOUT_IN_SECONDS, TimeUnit.SECONDS);
File cacheDir = new File(context.getCacheDir(), "http");
final Cache cache = new Cache(cacheDir, DISK_CACHE_SIZE_IN_BYTES);
okHttpClient.setCache(cache);
okHttpClient.interceptors().add(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Response response = chain.proceed(request);
Response finalResponse = response.newBuilder()
.header("Cache-Control", String.format("public, max-stale=%d", 604800))
.build();
Log.d("OkHttp", finalResponse.toString());
Log.d("OkHttp Headers", finalResponse.headers().toString());
return finalResponse;
}
});
return okHttpClient;
}
I did not forget to setClient on RestAdapter.Builder. Also made sure, that I'm actually using instance of RestAdapter with this client set.
Even checked if the files are created under "http" folder. They are.
However after I turn of WIFI and reload my screen I end up in OnError callback of Observable endpoint with this message:
retrofit.RetrofitError: failed to connect to /10.40.31.12 (port 8888) after 10000ms: connect failed: ENETUNREACH (Network is unreachable)
DISCLAIMER: I should probably mention that the final Observable is combined from 5 others, with flatMap and zip on the way.

I think I have an answer. Short one is: "Cannot be done if server sends no-cache header in response".
If you want the longer one, details are below.
I've made a sample app comparing 2 backends. Lets call them Backend A, and Backend B. A was giving me troubles so I've decided to check on B.
A returns CacheControl = "no-cache, no-transform, max-age=0"
B returns Cache-Control = „public" response header
I did the same setup for both backends, just different urls.
private void buildApi() {
Gson gson = new GsonBuilder().create();
OkHttpClient okHttpClient = new OkHttpClient();
okHttpClient.setConnectTimeout(10, TimeUnit.SECONDS);
File cacheDir = new File(getCacheDir(), "http");
final Cache cache = new Cache(cacheDir, 1000000 * 10);
okHttpClient.setCache(cache);
okHttpClient.interceptors().add(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
Log.d("OkHttp REQUEST", request.toString());
Log.d("OkHttp REQUEST Headers", request.headers().toString());
Response response = chain.proceed(request);
response = response.newBuilder()
.header("Cache-Control", String.format("public, max-age=%d, max-stale=%d", 60, RESPONSE_CACHE_LIFESPAN_IN_SECONDS))
.build();
Log.d("OkHttp RESPONSE", response.toString());
Log.d("OkHttp RESPONSE Headers", response.headers().toString());
return response;
}
});
RestAdapter.Builder builder = new RestAdapter.Builder()
.setConverter(new StringGsonConverter(gson))
.setClient(new OkClient(okHttpClient))
.setRequestInterceptor(new RequestInterceptor() {
#Override
public void intercept(RequestFacade request) {
if (isNetworkAvailable()) {
request.addHeader("Cache-Control", "public, max-age=" + 60);
} else {
request.addHeader("Cache-Control", "public, only-if-cached, max-stale=" + RESPONSE_CACHE_LIFESPAN_IN_SECONDS);
}
}
});
builder.setEndpoint("http://this.is.under.vpn.so.wont.work.anyway/api");
A_API = builder.build().create(AApi.class);
builder.setEndpoint("http://collector-prod-server.elasticbeanstalk.com/api");
B_API = builder.build().create(BApi.class);
}
Did both calls, then disabled wifi.
Cache worked fine for B, but A thrown 504 Unsatisfiable Request (only-if-cached)
It seems that overwritting headers won't help in that case.

You should rewrite your Request instead of the Response. For reference, see the docs on rewriting requests. Note you, can also use the CacheControl class instead of building your own header if you want. Your interceptor should look something like --
okHttpClient.interceptors().add(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
Request cachedRequest = request.newBuilder()
.cacheControl(new CacheControl.Builder()
.maxStale(7, TimeUnit.DAYS)
.build())
.build();
return chain.proceed(cachedRequest);
}
});

How Retrofit with OKHttp use cache data when offline

I want to Retrofit with OkHttp uses cache when is no Internet.
I prepare OkHttpClient like this:
RestAdapter.Builder builder= new RestAdapter.Builder()
.setRequestInterceptor(new RequestInterceptor() {
#Override
public void intercept(RequestFacade request) {
request.addHeader("Accept", "application/json;versions=1");
if (MyApplicationUtils.isNetworkAvaliable(context)) {
int maxAge = 60; // read from cache for 1 minute
request.addHeader("Cache-Control", "public, max-age=" + maxAge);
} else {
int maxStale = 60 * 60 * 24 * 28; // tolerate 4-weeks stale
request.addHeader("Cache-Control",
"public, only-if-cached, max-stale=" + maxStale);
}
}
});
and setting cache like this:
Cache cache = null;
try {
cache = new Cache(httpCacheDirectory, 10 * 1024 * 1024);
} catch (IOException e) {
Log.e("OKHttp", "Could not create http cache", e);
}
OkHttpClient okHttpClient = new OkHttpClient();
if (cache != null) {
okHttpClient.setCache(cache);
}
and I checked on rooted device, that in cache directory are saving files with the "Response headers" and Gzip files.
But I don't get the correct answer from retrofit cache in offline, although in GZip file is coded my correct answer. So how can I make Retrofit can read GZip file and how can he know which file it should be (because I have a few files there with other responses) ?

I have simlar problem in my company :)
The problem was on server side. In serwer response i have:
Pragma: no-cache
So when i removed this everything starts working. Before i removed it i get all the time such exceptions: 504 Unsatisfiable Request (only-if-cached)
Ok so how implementation on my side looks.
OkHttpClient okHttpClient = new OkHttpClient();
File httpCacheDirectory = new File(appContext.getCacheDir(), "responses");
Cache cache = new Cache(httpCacheDirectory, maxSizeInBytes);
okHttpClient.setCache(cache);
OkClient okClient = new OkClient(okHttpClient);
RestAdapter.Builder builder = new RestAdapter.Builder();
builder.setEndpoint(endpoint);
builder.setClient(okClient);
If you have problems in testing on which side is problem (server or app). You can use such feauture to set headers received from server.
private static final Interceptor REWRITE_CACHE_CONTROL_INTERCEPTOR = new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Response originalResponse = chain.proceed(chain.request());
return originalResponse.newBuilder()
.removeHeader("Pragma")
.header("Cache-Control",
String.format("max-age=%d", 60))
.build();
}
};
and simply add it:
okHttpClient.networkInterceptors().add(REWRITE_CACHE_CONTROL_INTERCEPTOR);
Thanks to that as you can see i was able to remove Pragma: no-cache header for test time.
Also i suggest you to read about Cache-Control header:
max-age,max-stale
Other usefull links:
List of HTTP header fields
Cache controll
Another sample code