OkHttp3 Never Timeout on slow internet

As pointed out by Trevor Halvorson, you could set callTimeout during client builder, in this way:

OkHttpClient client = new OkHttpClient.Builder()
            .connectTimeout(20, TimeUnit.SECONDS)
            .callTimeout(20, TimeUnit.SECONDS)
            .writeTimeout(20, TimeUnit.SECONDS)
            .readTimeout(20, TimeUnit.SECONDS)
            .retryOnConnectionFailure(false)
            .build();

I've personally tested in a dummy project using version 3.14.0 of okhttp3:

implementation 'com.squareup.okhttp3:okhttp:3.14.0'

And setting a timout of 5 seconds and my emulator connection to GPRS and Poor connectivity I get

java.net.SocketExcpetion: Socket closed: timeout

This is my full dummy activity:

package com.example.shadowsheep.myapplication;

import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

import java.io.IOException;
import java.io.InterruptedIOException;
import java.util.concurrent.TimeUnit;

import androidx.appcompat.app.AppCompatActivity;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final TextView helloTextView = findViewById(R.id.helloTextView);

        OkHttpClient client = new OkHttpClient.Builder()
                .connectTimeout(5, TimeUnit.SECONDS)
                .callTimeout(5, TimeUnit.SECONDS)
                .writeTimeout(5, TimeUnit.SECONDS)
                .readTimeout(5, TimeUnit.SECONDS)
                .retryOnConnectionFailure(false)
                .build();

        Request request = new Request.Builder()
                .url("https://www.versionestabile.it/blog")
                .build();

        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                e.printStackTrace();
                Log.d("OKHTTP3", e.getMessage());
                // You get this failure
                runOnUiThread(() -> helloTextView.setText("TIMEOUT - FAILURE -> " + e.getMessage()));
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                try {
                    final String _body = response.body().string();
                    Log.d("OKHTTP3", _body);
                    runOnUiThread(() -> {
                        helloTextView.setText(_body);
                    });
                } catch (InterruptedIOException e) {
                    runOnUiThread(() -> {
                        // Or this exception depending when timeout is reached
                        helloTextView.setText("TIMEOUT EXCEPTION->"+ e.getCause() + ": " + e.getMessage());
                    });
                }
            }
        });
    }
}

I'll give you also my app build.gradle file.

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.shadowsheep.myapplication"
        minSdkVersion 24
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility 1.8
        targetCompatibility 1.8
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.1.0-alpha03'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.2-alpha02'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0-alpha02'

    implementation 'com.squareup.okhttp3:okhttp:3.14.0'
}

My test case won't work too, it takes 30+ seconds every time:

• Android Emulator Nexus 4 (Android Version 4.1.2)
• Windows 7 With no internet connection (Ensure emulator with no internet connection)

gradle:

implementation 'com.squareup.okhttp3:okhttp:3.12.2'

defaultConfig {
    minSdkVersion 16
    targetSdkVersion 26
}
compileSdkVersion 27
buildToolsVersion '28.0.3'

java:

public static class CheckIpAsyncTask extends util.android.os.AsyncTask<Void, Void, Void> {

@Override
    protected Void doInBackground(Void... voids) {
        try {
        Logger.i(TAG, "API::FBD::checkIpInfo, API_IPINFO = " + API_IPINFO);
        if (BuildConfig.DEBUG) {
            //ThreadUtil.sleep(10 * TimeUtil.SECOND);
        }

        Request req = new Request.Builder()
                .get()
                .url(API_IPINFO)
                .build();
        OkHttpClient client = new OkHttpClient.Builder()
                .connectTimeout(2, TimeUnit.SECONDS)
                .callTimeout(2, TimeUnit.SECONDS)
                .readTimeout(2, TimeUnit.SECONDS)
                .writeTimeout(2, TimeUnit.SECONDS)
                .build();
        Response response = client.newCall(req).execute();

        mHttpCode = response.code();
        if (mHttpCode == HttpURLConnection.HTTP_OK) {
            boolean appConnected = ServerHelper.checkAppConnected();
            if (!appConnected) {
                JSONObject res = new JSONObject(response.body().string().trim());
                mCountry = res.getString("country").toLowerCase();
                mIp = res.getString("ip").toLowerCase();
                Logger.i(TAG, "API::FBD::checkIpInfo, res = " + res);

                PreferenceHelper.get(mContext).setIpInfoApiCountry(mCountry);
                PreferenceHelper.get(mContext).setIpInfoApiHost(mIp);
            }
        }
    } catch (java.io.InterruptedIOException interruptedIOException) {
        Logger.e(TAG, "API::FBD::checkIpInfo, InterruptedIOException=" + interruptedIOException);
    } catch (Throwable ignored) {
        Logger.e(TAG, "API::FBD::checkIpInfo, Throwable=" + ignored);
    }
    return null;
}

logs:

04-04 06:25:06.940 4492-4645/? I/Toolbox: [PLACE] at com.xy.ui.FbdUtil$CheckIpAsyncTask.doInBackground(FbdUtil.java:98)
                                          [FbdUtil]API::FBD::checkIpInfo, API_IPINFO = http://api.z.com:30070/servers/ipinfo
04-04 06:25:34.960 4492-4645/? E/Toolbox: [PLACE] at com.xy.ui.FbdUtil$CheckIpAsyncTask.doInBackground(FbdUtil.java:129)
                                          [FbdUtil]API::FBD::checkIpInfo, InterruptedIOException=java.io.InterruptedIOException: timeout

logs on Emulator Nexus 6 (Android version 8.0):

04-04 06:52:44.696 2624-3950/? I/Toolbox: [PLACE] at com.xy.ui.FbdUtil$CheckIpAsyncTask.doInBackground(FbdUtil.java:98)
                                          [FbdUtil]API::FBD::checkIpInfo, API_IPINFO = http://api.z.com:30070/servers/ipinfo
04-04 06:53:59.886 2624-3175/? E/Toolbox: [PLACE] at com.xy.ui.ForbiddenUtil$CheckIpAsyncTask.doInBackground(FbdUtil.java:129)
                                          [FbdUtil]API::FBD::checkIpInfo, InterruptedIOException=java.io.InterruptedIOException: timeout

Finally, Dmitry Zenovich's solution in 'Question 6' works for me:

.dns(hostname -> Single.fromCallable(() -> Arrays.asList(InetAddress.getAllByName(hostname)))
                            .timeout(2, TimeUnit.SECONDS)
                            .subscribeOn(Schedulers.io())
                            .observeOn(Schedulers.computation())
                            .onErrorReturnItem(new ArrayList<>())
                            .blockingGet())