Allow for changing the okhttpclientprovider builder

ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.java

@@ -31,29 +31,45 @@ public class OkHttpClientProvider {
 
   // Centralized OkHttpClient for all networking requests.
   private static @Nullable OkHttpClient sClient;
+  private static @Nullable OkHttpClient.Builder sClientBuilder;
 
   public static OkHttpClient getOkHttpClient() {
     if (sClient == null) {
       sClient = createClient();
     }
     return sClient;
   }
-
-  // okhttp3 OkHttpClient is immutable
-  // This allows app to init an OkHttpClient with custom settings.
+
+  /**
+   * okhttp3 OkHttpClient is immutable
+   * This allows app to init an OkHttpClient with custom settings.
+   * @deprecated Use {@link #replaceOkHttpClientBuilder(OkHttpClient.Builder)} instead.
+   */
+  @Deprecated
   public static void replaceOkHttpClient(OkHttpClient client) {
     sClient = client;
   }
 
+  /**
+   * Replace the builder used by {@link #createClient()}
+   */
+  public static void replaceOkHttpClientBuilder(OkHttpClient.Builder builder) {
+    sClientBuilder = builder;
+  }
+
   public static OkHttpClient createClient() {
-    // No timeouts by default
-    OkHttpClient.Builder client = new OkHttpClient.Builder()
-      .connectTimeout(0, TimeUnit.MILLISECONDS)
-      .readTimeout(0, TimeUnit.MILLISECONDS)
-      .writeTimeout(0, TimeUnit.MILLISECONDS)
-      .cookieJar(new ReactCookieJarContainer());
-
-    return enableTls12OnPreLollipop(client).build();
+    if (sClientBuilder != null) {
+      return sClientBuilder.build();
+    } else {
+      // No timeouts by default
+      OkHttpClient.Builder client = new OkHttpClient.Builder()
+        .connectTimeout(0, TimeUnit.MILLISECONDS)
+        .readTimeout(0, TimeUnit.MILLISECONDS)
+        .writeTimeout(0, TimeUnit.MILLISECONDS)
+        .cookieJar(new ReactCookieJarContainer());
+
+      return enableTls12OnPreLollipop(client).build();
+    }
   }
 
   /*

ReactAndroid/src/test/java/com/facebook/react/modules/network/OkHttpClientProviderTest.java

@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.react.modules.network;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.powermock.core.classloader.annotations.PowerMockIgnore;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.robolectric.RobolectricTestRunner;
+
+import okhttp3.OkHttpClient;
+
+import static org.fest.assertions.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+/**
+ * Tests for {@link OkHttpClientProvider}.
+ */
+@PrepareForTest({
+    OkHttpClient.class,
+    OkHttpClient.Builder.class
+})
+@RunWith(RobolectricTestRunner.class)
+@PowerMockIgnore({"org.mockito.*", "org.robolectric.*", "android.*"})
+public class OkHttpClientProviderTest {
+
+  @Test
+  public void testReplaceOkHttpClientBuilder() throws Exception {
+    OkHttpClient httpClient = mock(OkHttpClient.class);
+    OkHttpClient.Builder clientBuilder = mock(OkHttpClient.Builder.class);
+    when(clientBuilder.build()).thenReturn(httpClient);
+    when(httpClient.newBuilder()).thenReturn(clientBuilder);
+
+    OkHttpClientProvider.replaceOkHttpClientBuilder(clientBuilder);
+    assertThat(OkHttpClientProvider.createClient()).isEqualTo(httpClient);
+
+    OkHttpClientProvider.replaceOkHttpClientBuilder(null);
+    assertThat(OkHttpClientProvider.createClient()).isNotEqualTo(httpClient);
+  }
+}