feat: allow user-specified default OkHttpClient instance

src/main/java/com/ibm/cloud/sdk/core/http/HttpClientSingleton.java

@@ -153,7 +153,25 @@ protected HttpClientSingleton() {
   }
 
   /**
-   * Configures the HTTP client.
+   * Returns the current {@link OkHttpClient} instance held by this singleton.
+   * This is the client instance that is used as a default configuration from which other client instances are built.
+   * @return the current OkHttpClient instance
+   */
+  public OkHttpClient getHttpClient() {
+    return this.okHttpClient;
+  }
+
+  /**
+   * Sets the current {@link OkHttpClient} instance held by this singleton.
+   * This is the client instance that is used as a default configuration from which other client instances are built.
+   * @param client the new OkHttpClient instance to use as a default client configuration
+   */
+  public void setHttpClient(OkHttpClient client) {
+    this.okHttpClient = client;
+  }
+
+  /**
+   * Configures a new HTTP client instance.
    *
    * @return the HTTP client
    */
@@ -290,7 +308,7 @@ private OkHttpClient setLoggingLevel(OkHttpClient client, LoggingLevel loggingLe
    *
    * @param builder the {@link OkHttpClient} builder.
    */
-  private void setupTLSProtocol(final OkHttpClient.Builder builder) {
+  public static void setupTLSProtocol(final OkHttpClient.Builder builder) {
     try {
       TrustManagerFactory trustManagerFactory =
           TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());

src/main/java/com/ibm/cloud/sdk/core/security/TokenRequestBasedAuthenticator.java

@@ -1,5 +1,5 @@
 /**
- * (C) Copyright IBM Corp. 2019, 2021.
+ * (C) Copyright IBM Corp. 2019, 2022.
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
  * the License. You may obtain a copy of the License at
@@ -40,16 +40,20 @@
  * <ul>
  * <li>disableSSLVerification - a flag that indicates whether or not client-side SSL verification should be disabled.
  * <li>headers - a Map of keys/values that will be set as HTTP headers on requests sent to the token service.
- * <li>proxy - a java.net.Proxy instance that will be set on the Client object used to interact with the token service.
- * <li>proxyAuthenticator - an okhttp3.Authenticator instance to be set on the Client object used to interact wth
- * the token service.
+ * <li>proxy - a java.net.Proxy instance that will be set on the OkHttpClient instance used to
+ * interact with the token service.
+ * <li>proxyAuthenticator - an okhttp3.Authenticator instance to be set on the OkHttpClient instance used to
+ * interact with the token service.
+ * <li>client - a fully-configured OkHttpClient instance to be used to interact with the token service.
  * </ul>
  */
 public abstract class TokenRequestBasedAuthenticator<T extends AbstractToken, R extends TokenServerResponse>
   extends AuthenticatorBase implements Authenticator {
 
   private static final Logger logger = Logger.getLogger(TokenRequestBasedAuthenticator.class.getName());
 
+  protected OkHttpClient client;
+
   // Configuration properties that are common to all subclasses.
   private boolean disableSSLVerification;
   private Map<String, String> headers;
@@ -67,6 +71,47 @@ private void setTokenData(T tokenData) {
     this.tokenData = tokenData;
   }
 
+  /**
+   * Sets the OkHttpClient instance to be used when interacting with the token service.
+   * @param client the OkHttpClient instance to use
+   */
+  public void setClient(OkHttpClient client) {
+    this.client = client;
+  }
+
+  /**
+   * Returns the OkHttpClient instance to be used when interacting with the token service.
+   * @return the client instance or null if a client insance has not yet been set
+   */
+  public OkHttpClient getClient() {
+    return this.client;
+  }
+
+  /**
+   * Returns a properly-configured OkHttpClient instance to use when interacting with the token service.
+   * This function is different from "getClient()" in that it will configure and save
+   * a client instance if one has not yet been setup for "this".
+   * @return a non-null, configured OkHttpClient instance
+   */
+  protected synchronized OkHttpClient getConfiguredClient() {
+    if (this.client == null) {
+      OkHttpClient defaultClient = HttpClientSingleton.getInstance().getHttpClient();
+
+      HttpConfigOptions.Builder clientOptions = new HttpConfigOptions.Builder()
+          .disableSslVerification(this.disableSSLVerification)
+          .proxy(this.proxy)
+          .proxyAuthenticator(this.proxyAuthenticator);
+
+      if (logger.isLoggable(Level.FINE)) {
+        clientOptions.loggingLevel(LoggingLevel.BODY);
+      }
+
+      this.client = HttpClientSingleton.getInstance().configureClient(defaultClient, clientOptions.build());
+    }
+
+    return this.client;
+  }
+
   /**
    * Validates the configuration properties associated with the Authenticator.
    * Each concrete subclass must implement this method.
@@ -136,7 +181,7 @@ public Proxy getProxy() {
 
   /**
    * Sets a Proxy object on this Authenticator.
-   * @param proxy the proxy object to be associated with the Client used to interact wth the token service.
+   * @param proxy the proxy object to be associated with the Client used to interact with the token service.
    */
   public void setProxy(Proxy proxy) {
     this.proxy = proxy;
@@ -256,18 +301,7 @@ protected R invokeRequest(final RequestBuilder requestBuilder, final Class<? ext
     // Allocate the response.
     final Object[] responseObj = new Object[1];
 
-    // Set up the Client we'll use to invoke the request.
-    final HttpConfigOptions.Builder clientOptions = new HttpConfigOptions.Builder()
-        .disableSslVerification(this.disableSSLVerification)
-        .proxy(this.proxy)
-        .proxyAuthenticator(this.proxyAuthenticator);
-
-    // Enable request/response logging.
-    if (logger.isLoggable(Level.FINE)) {
-      clientOptions.loggingLevel(LoggingLevel.BODY);
-    }
-
-    final OkHttpClient client = HttpClientSingleton.getInstance().configureClient(clientOptions.build());
+    final OkHttpClient client = getConfiguredClient();
 
     final Request request = requestBuilder.build();
 

src/test/java/com/ibm/cloud/sdk/core/security/VpcInstanceAuthenticatorTest.java

@@ -20,6 +20,7 @@
 import static org.testng.Assert.assertTrue;
 import static org.testng.Assert.fail;
 
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
@@ -38,7 +39,9 @@
 import com.ibm.cloud.sdk.core.test.BaseServiceUnitTest;
 import com.ibm.cloud.sdk.core.util.Clock;
 
+import okhttp3.ConnectionSpec;
 import okhttp3.Headers;
+import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.mockwebserver.RecordedRequest;
 
@@ -404,6 +407,19 @@ public void testAuthenticateNewAndCachedToken() throws Throwable {
         .url(url)
         .build();
 
+    // Create a custom client and set it on the authenticator.
+    ConnectionSpec spec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+        .allEnabledCipherSuites()
+        .build();
+    OkHttpClient client = new OkHttpClient.Builder()
+        .connectTimeout(30, TimeUnit.SECONDS)
+        .writeTimeout(120, TimeUnit.SECONDS)
+        .readTimeout(120, TimeUnit.SECONDS)
+        .connectionSpecs(Arrays.asList(spec, ConnectionSpec.CLEARTEXT))
+        .build();
+    authenticator.setClient(client);
+    assertEquals(authenticator.getClient(), client);
+
     Request.Builder requestBuilder = new Request.Builder().url("https://test.com");
 
     // Set mock server responses.
@@ -422,6 +438,9 @@ public void testAuthenticateNewAndCachedToken() throws Throwable {
     requestBuilder = new Request.Builder().url("https://test.com");
     authenticator.authenticate(requestBuilder);
     verifyAuthHeader(requestBuilder, "Bearer " + vpcIamAccessTokenResponse1.getAccessToken());
+
+    // Verify that the authenticator is still using the same client instance that we set before.
+    assertEquals(authenticator.getClient(), client);
   }
 
   @Test

src/test/java/com/ibm/cloud/sdk/core/test/http/HttpClientSingletonTest.java

@@ -14,13 +14,16 @@
 package com.ibm.cloud.sdk.core.test.http;
 
 import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotEquals;
+import static org.testng.Assert.assertNotNull;
 import static org.testng.Assert.assertTrue;
 
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 
 import javax.net.ssl.SSLSocket;
 
@@ -126,4 +129,45 @@ public void testSetRetryStrategy() {
       assertEquals(testRetryInterceptors, 1);
       assertEquals(otherRetryInterceptors, 0);
     }
+
+    @Test
+    public void testSetClient() {
+
+      // Create a custom client and set it on the HttpClientSingleton
+      // as the default for configuring other clients.
+      ConnectionSpec spec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+          .allEnabledCipherSuites()
+          .build();
+      OkHttpClient client = new OkHttpClient.Builder()
+          .connectTimeout(30, TimeUnit.SECONDS)
+          .writeTimeout(120, TimeUnit.SECONDS)
+          .readTimeout(120, TimeUnit.SECONDS)
+          .connectionSpecs(Arrays.asList(spec, ConnectionSpec.CLEARTEXT))
+          .build();
+      HttpClientSingleton cs = HttpClientSingleton.getInstance();
+      assertNotNull(cs.getHttpClient());
+
+      // Verify set/get.
+      cs.setHttpClient(client);
+      assertEquals(cs.getHttpClient(), client);
+
+      // Verify that "client" is used to configure other clients.
+      // To verify this, we'll just configure a new client with SSL verification disabled,
+      // and its timeout properties should be the same as what we set above on our original client.
+      HttpConfigOptions options = new HttpConfigOptions.Builder()
+          .disableSslVerification(true)
+          .build();
+      OkHttpClient client2 = cs.configureClient(options);
+
+      // Verify that the "configureClient()" call above set a new default client instance in the singleton.
+      assertNotEquals(cs.getHttpClient(), client);
+
+      // Verify that the new client is a different instance than our original client.
+      assertNotEquals(client2, client);
+
+      // Verify that the new client "inherits" the config from our original client.
+      assertEquals(client2.connectTimeoutMillis(), 30 * 1000);
+      assertEquals(client2.writeTimeoutMillis(), 120 * 1000);
+      assertEquals(client2.readTimeoutMillis(), 120 * 1000);
+    }
   }

src/test/java/com/ibm/cloud/sdk/core/test/security/ContainerAuthenticatorTest.java

@@ -22,6 +22,7 @@
 import static org.testng.Assert.fail;
 
 import java.nio.file.NoSuchFileException;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
@@ -45,7 +46,9 @@
 import com.ibm.cloud.sdk.core.test.BaseServiceUnitTest;
 import com.ibm.cloud.sdk.core.util.Clock;
 
+import okhttp3.ConnectionSpec;
 import okhttp3.Headers;
+import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.mockwebserver.RecordedRequest;
 
@@ -249,6 +252,19 @@ public void testAuthenticateNewAndStoredToken() throws Throwable {
         .url(url)
         .build();
 
+    // Create a custom client and set it on the authenticator.
+    ConnectionSpec spec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+        .allEnabledCipherSuites()
+        .build();
+    OkHttpClient client = new OkHttpClient.Builder()
+        .connectTimeout(30, TimeUnit.SECONDS)
+        .writeTimeout(120, TimeUnit.SECONDS)
+        .readTimeout(120, TimeUnit.SECONDS)
+        .connectionSpecs(Arrays.asList(spec, ConnectionSpec.CLEARTEXT))
+        .build();
+    authenticator.setClient(client);
+    assertEquals(authenticator.getClient(), client);
+
     Request.Builder requestBuilder = new Request.Builder().url("https://test.com");
 
     // Set mock server response.
@@ -280,6 +296,9 @@ public void testAuthenticateNewAndStoredToken() throws Throwable {
     requestBuilder = new Request.Builder().url("https://test.com");
     authenticator.authenticate(requestBuilder);
     verifyAuthHeader(requestBuilder, "Bearer " + tokenData1.getAccessToken());
+
+    // Verify that the authenticator is still using the same client instance that we set before.
+    assertEquals(authenticator.getClient(), client);
   }
 
   @Test

src/test/java/com/ibm/cloud/sdk/core/test/security/Cp4dAuthenticatorTest.java

@@ -21,6 +21,7 @@
 import static org.testng.Assert.assertTrue;
 import static org.testng.Assert.fail;
 
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
@@ -39,7 +40,9 @@
 import com.ibm.cloud.sdk.core.test.BaseServiceUnitTest;
 import com.ibm.cloud.sdk.core.util.Clock;
 
+import okhttp3.ConnectionSpec;
 import okhttp3.Headers;
+import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.mockwebserver.RecordedRequest;
 
@@ -312,17 +315,32 @@ public void testAuthenticateNewAndStoredToken() {
         .password(testPassword)
         .disableSSLVerification(true)
         .build();
-    Request.Builder requestBuilder;
+
+    // Create a custom client and set it on the authenticator.
+    ConnectionSpec spec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+        .allEnabledCipherSuites()
+        .build();
+    OkHttpClient client = new OkHttpClient.Builder()
+        .connectTimeout(30, TimeUnit.SECONDS)
+        .writeTimeout(120, TimeUnit.SECONDS)
+        .readTimeout(120, TimeUnit.SECONDS)
+        .connectionSpecs(Arrays.asList(spec, ConnectionSpec.CLEARTEXT))
+        .build();
+    authenticator.setClient(client);
+    assertEquals(authenticator.getClient(), client);
 
     // Authenticator should request new, valid token.
-    requestBuilder = new Request.Builder().url("https://test.com");
+     Request.Builder requestBuilder = new Request.Builder().url("https://test.com");
     authenticator.authenticate(requestBuilder);
     verifyAuthHeader(requestBuilder, "Bearer " + tokenData.getToken());
 
     // Authenticator should just return the same token this time since we have a valid one stored.
     requestBuilder = new Request.Builder().url("https://test.com");
     authenticator.authenticate(requestBuilder);
     verifyAuthHeader(requestBuilder, "Bearer " + tokenData.getToken());
+
+    // Verify that the authenticator is still using the same client instance that we set before.
+    assertEquals(authenticator.getClient(), client);
   }
 
   @Test