Add cleartext traffic check

dependencies.gradle

@@ -51,6 +51,8 @@ ext.versions = [
 ]
 
 ext.libs = [
+    android: "org.robolectric:android-all:10-robolectric-5803371",
+
     appCompat: "androidx.appcompat:appcompat:$versions.appCompat",
     material: "com.google.android.material:material:$versions.material",
     multiDex: "androidx.multidex:multidex:$versions.multiDex",

scarlet-websocket-okhttp/build.gradle

@@ -9,6 +9,7 @@ dependencies {
     implementation project(':scarlet-core-internal')
     implementation libs.rxJava
     implementation libs.kotlin.stdlib
+    compileOnly libs.android
 
     testImplementation project(':scarlet')
     testImplementation project(':scarlet-websocket-mockwebserver')

scarlet-websocket-okhttp/src/main/java/com/tinder/scarlet/websocket/okhttp/OkHttpClientUtils.kt

@@ -6,15 +6,34 @@
 
 package com.tinder.scarlet.websocket.okhttp
 
+import android.os.Build
+import android.security.NetworkSecurityPolicy
 import com.tinder.scarlet.WebSocket
 import com.tinder.scarlet.websocket.okhttp.request.RequestFactory
 import com.tinder.scarlet.websocket.okhttp.request.StaticUrlRequestFactory
+import okhttp3.HttpUrl
 import okhttp3.OkHttpClient
+import java.net.UnknownServiceException
 
 fun OkHttpClient.newWebSocketFactory(requestFactory: RequestFactory): WebSocket.Factory {
     return OkHttpWebSocket.Factory(OkHttpClientWebSocketConnectionEstablisher(this, requestFactory))
 }
 
 fun OkHttpClient.newWebSocketFactory(url: String): WebSocket.Factory {
+    if (url.startsWith("ws:", ignoreCase = true)) {
+        try {
+            if ((Build.VERSION.SDK_INT > 23 &&
+                            !NetworkSecurityPolicy.getInstance().isCleartextTrafficPermitted(
+                                    HttpUrl.parse("http:${url.substring(3)}")?.host())) ||
+                    (Build.VERSION.SDK_INT == 23 &&
+                            !NetworkSecurityPolicy.getInstance().isCleartextTrafficPermitted)) {
+                throw UnknownServiceException(
+                        "CLEARTEXT communication to $url not permitted by network security policy")
+            }
+        } catch (_: ClassNotFoundException) {
+            // Not running on Android
+        }
+    }
+
     return newWebSocketFactory(StaticUrlRequestFactory(url))
 }