Add executorService API to ManagedIdentityCredentialBuilder (#43703)

This is the only builder that uses MSAL and was lacking the `executorService` API. Refined comments in other places to reflect the current reality of using the `SharedExecutorService` if nothing is configured.

sdk/identity/azure-identity/CHANGELOG.md

@@ -3,6 +3,7 @@
 ## 1.15.0-beta.1 (Unreleased)
 
 ### Features Added
+- Added missing `executorService` API to `ManagedIdentityCredentialBuilder`, cleaned up comments in other types for this method.
 
 ### Breaking Changes
 

sdk/identity/azure-identity/src/main/java/com/azure/identity/AadCredentialBuilderBase.java

@@ -10,7 +10,6 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.ForkJoinPool;
 
 /**
  * <p>The base class for credential builders that allow specifying a client ID, tenant ID, authority host, and
@@ -73,9 +72,9 @@ public T tenantId(String tenantId) {
      * Developer is responsible for maintaining the lifecycle of the ExecutorService.
      *
      * <p>
-     * If this is not configured, the {@link ForkJoinPool#commonPool() common fork join pool} will be used which is
-     * also shared with other application tasks. If the common pool is heavily used for other tasks, authentication
-     * requests might starve and setting up this executor service should be considered.
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
      * </p>
      *
      * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the

sdk/identity/azure-identity/src/main/java/com/azure/identity/AzureApplicationCredentialBuilder.java

@@ -9,7 +9,6 @@
 
 import java.util.ArrayList;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.ForkJoinPool;
 
 /**
  * Fluent credential builder for instantiating a {@link AzureApplicationCredential}.
@@ -71,9 +70,9 @@ public AzureApplicationCredentialBuilder managedIdentityResourceId(String resour
      * Developer is responsible for maintaining the lifecycle of the ExecutorService.
      *
      * <p>
-     * If this is not configured, the {@link ForkJoinPool#commonPool()} will be used which is
-     * also shared with other application tasks. If the common pool is heavily used for other tasks, authentication
-     * requests might starve and setting up this executor service should be considered.
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
      * </p>
      *
      * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the

sdk/identity/azure-identity/src/main/java/com/azure/identity/DefaultAzureCredentialBuilder.java

@@ -17,7 +17,6 @@
 import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.ForkJoinPool;
 
 /**
  * <p>Fluent credential builder for instantiating {@link DefaultAzureCredential}.</p>
@@ -170,9 +169,9 @@ public DefaultAzureCredentialBuilder managedIdentityResourceId(String resourceId
      * Developer is responsible for maintaining the lifecycle of the ExecutorService.
      *
      * <p>
-     * If this is not configured, the {@link ForkJoinPool#commonPool() common fork join pool} will be used which is
-     * also shared with other application tasks. If the common pool is heavily used for other tasks, authentication
-     * requests might starve and setting up this executor service should be considered.
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
      * </p>
      *
      * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the

sdk/identity/azure-identity/src/main/java/com/azure/identity/EnvironmentCredentialBuilder.java

@@ -8,7 +8,6 @@
 import com.azure.identity.implementation.util.ValidationUtil;
 
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.ForkJoinPool;
 
 /**
  * Fluent credential builder for instantiating a {@link EnvironmentCredential}.
@@ -60,9 +59,9 @@ public EnvironmentCredentialBuilder authorityHost(String authorityHost) {
      * Developer is responsible for maintaining the lifecycle of the ExecutorService.
      *
      * <p>
-     * If this is not configured, the {@link ForkJoinPool#commonPool()} will be used which is
-     * also shared with other application tasks. If the common pool is heavily used for other tasks, authentication
-     * requests might starve and setting up this executor service should be considered.
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
      * </p>
      *
      * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the

sdk/identity/azure-identity/src/main/java/com/azure/identity/ManagedIdentityCredentialBuilder.java

@@ -6,6 +6,8 @@
 import com.azure.core.util.logging.ClientLogger;
 import com.azure.identity.implementation.util.ValidationUtil;
 
+import java.util.concurrent.ExecutorService;
+
 /**
  * <p>Fluent credential builder for instantiating a {@link ManagedIdentityCredential}.</p>
  *
@@ -106,6 +108,27 @@ public ManagedIdentityCredentialBuilder objectId(String objectId) {
         return this;
     }
 
+    /**
+     * Specifies the ExecutorService to be used to execute the authentication requests.
+     * Developer is responsible for maintaining the lifecycle of the ExecutorService.
+     *
+     * <p>
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
+     * </p>
+     *
+     * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the
+     * Azure SDK clients and should be shutdown before the application exits. </p>
+     *
+     * @param executorService the executor service to use for executing authentication requests.
+     * @return the ManagedIdentityCredentialBuilder itself
+     */
+    public ManagedIdentityCredentialBuilder executorService(ExecutorService executorService) {
+        this.identityClientOptions.setExecutorService(executorService);
+        return this;
+    }
+
     /**
      * Creates a new {@link ManagedIdentityCredential} with the current configurations.
      *

sdk/identity/azure-identity/src/main/java/com/azure/identity/implementation/IdentityClientOptions.java

@@ -13,8 +13,8 @@
 import com.azure.core.util.ClientOptions;
 import com.azure.core.util.Configuration;
 import com.azure.core.util.logging.ClientLogger;
-import com.azure.identity.AzureAuthorityHosts;
 import com.azure.identity.AuthenticationRecord;
+import com.azure.identity.AzureAuthorityHosts;
 import com.azure.identity.BrowserCustomizationOptions;
 import com.azure.identity.ChainedTokenCredential;
 import com.azure.identity.TokenCachePersistenceOptions;
@@ -29,7 +29,6 @@
 import java.util.Set;
 import java.util.TreeSet;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.ForkJoinPool;
 import java.util.function.Function;
 
 /**
@@ -214,9 +213,9 @@ public IdentityClientOptions setHttpPipeline(HttpPipeline httpPipeline) {
      * Developer is responsible for maintaining the lifecycle of the ExecutorService.
      *
      * <p>
-     * If this is not configured, the {@link ForkJoinPool#commonPool() common fork join pool} will be used which is
-     * also shared with other application tasks. If the common pool is heavily used for other tasks, authentication
-     * requests might starve and setting up this executor service should be considered.
+     * If this is not configured, the {@link com.azure.core.util.SharedExecutorService} will be used which is
+     * also shared with other SDK libraries. If there are many concurrent SDK tasks occurring, authentication
+     * requests might starve and configuring a separate executor service should be considered.
      * </p>
      *
      * <p> The executor service and can be safely shutdown if the TokenCredential is no longer being used by the