mgmt update default subscription logic

sdk/management/azure/src/main/java/com/azure/management/Azure.java

@@ -5,7 +5,6 @@
 
 import com.azure.core.credential.TokenCredential;
 import com.azure.core.http.HttpPipeline;
-import com.azure.core.util.logging.ClientLogger;
 import com.azure.management.appservice.AppServiceCertificateOrders;
 import com.azure.management.appservice.AppServiceCertificates;
 import com.azure.management.appservice.AppServiceDomains;
@@ -73,6 +72,8 @@
 import com.azure.management.network.implementation.NetworkManager;
 import com.azure.management.resources.Deployments;
 import com.azure.management.resources.GenericResources;
+import com.azure.management.resources.PolicyAssignments;
+import com.azure.management.resources.PolicyDefinitions;
 import com.azure.management.resources.Providers;
 import com.azure.management.resources.ResourceGroups;
 import com.azure.management.resources.Subscription;
@@ -83,6 +84,7 @@
 import com.azure.management.resources.fluentcore.profile.AzureProfile;
 import com.azure.management.resources.fluentcore.utils.HttpPipelineProvider;
 import com.azure.management.resources.fluentcore.utils.SdkContext;
+import com.azure.management.resources.fluentcore.utils.Utils;
 import com.azure.management.resources.implementation.ResourceManager;
 import com.azure.management.sql.SqlServers;
 import com.azure.management.sql.implementation.SqlServerManager;
@@ -229,17 +231,17 @@ public interface Authenticated extends AccessManagement {
          * Selects the default subscription as the subscription for the APIs to work with.
          *
          * <p>The default subscription can be specified inside the Azure profile using {@link
-         * AzureProfile}. If no default subscription has been previously provided, the first subscription as
-         * returned by {@link Authenticated#subscriptions()} will be selected.</p>
+         * AzureProfile}. If no default subscription provided, we will try to set the only
+         * subscription if applicable returned by {@link Authenticated#subscriptions()}</p>
          *
+         * @throws IllegalStateException when no subscription or more than one subscription found in the tenant.
          * @return an authenticated Azure client configured to work with the default subscription
          */
         Azure withDefaultSubscription();
     }
 
     /** The implementation for the Authenticated interface. */
     private static final class AuthenticatedImpl implements Authenticated {
-        private final ClientLogger logger = new ClientLogger(AuthenticatedImpl.class);
         private final HttpPipeline httpPipeline;
         private final AzureProfile profile;
         private final ResourceManager.Authenticated resourceManagerAuthenticated;
@@ -325,8 +327,7 @@ public Azure withSubscription(String subscriptionId) {
         @Override
         public Azure withDefaultSubscription() {
             if (profile.subscriptionId() == null) {
-                throw logger.logExceptionAsError(
-                    new IllegalArgumentException("Please specify the subscription ID for resource management."));
+                profile.withSubscriptionId(Utils.defaultSubscription(this.subscriptions().list()));
             }
             return new Azure(httpPipeline, profile, this);
         }
@@ -416,19 +417,19 @@ public Providers providers() {
         return resourceManager.providers();
     }
 
-    //    /**
-    //     * @return entry point to managing policy definitions.
-    //     */
-    //    public PolicyDefinitions policyDefinitions() {
-    //        return resourceManager.policyDefinitions();
-    //    }
-    //
-    //    /**
-    //     * @return entry point to managing policy assignments.
-    //     */
-    //    public PolicyAssignments policyAssignments() {
-    //        return resourceManager.policyAssignments();
-    //    }
+    /**
+     * @return entry point to managing policy definitions.
+     */
+    public PolicyDefinitions policyDefinitions() {
+        return resourceManager.policyDefinitions();
+    }
+
+    /**
+     * @return entry point to managing policy assignments.
+     */
+    public PolicyAssignments policyAssignments() {
+        return resourceManager.policyAssignments();
+    }
 
     /** @return entry point to managing storage accounts */
     public StorageAccounts storageAccounts() {

sdk/resources/mgmt/src/main/java/com/azure/management/resources/fluentcore/utils/Utils.java

@@ -7,17 +7,24 @@
 import com.azure.core.annotation.PathParam;
 import com.azure.core.http.HttpPipeline;
 import com.azure.core.http.HttpResponse;
+import com.azure.core.http.rest.PagedIterable;
 import com.azure.core.http.rest.RestProxy;
+import com.azure.core.util.logging.ClientLogger;
+import com.azure.management.resources.Subscription;
 import com.azure.management.resources.fluentcore.arm.ResourceId;
 import com.azure.management.resources.fluentcore.model.Indexable;
 import reactor.core.publisher.Mono;
 
+import java.util.ArrayList;
 import java.util.List;
 
 /**
  * Defines a few utilities.
  */
 public final class Utils {
+    private Utils() {
+    }
+
     /**
      * Converts an object Boolean to a primitive boolean.
      *
@@ -179,6 +186,32 @@ private interface FileService {
         Mono<HttpResponse> download(@PathParam("url") String url);
     }
 
-    private Utils() {
+    /**
+     * Gets the only subscription as the default one in the tenant if applicable.
+     *
+     * @param subscriptions the list of subscriptions
+     * @throws IllegalStateException when no subscription or more than one subscription found
+     * @return the only subscription existing in the tenant
+     */
+    public static String defaultSubscription(PagedIterable<Subscription> subscriptions) {
+        List<Subscription> subscriptionList = new ArrayList<>();
+        subscriptions.forEach(subscription -> {
+            subscriptionList.add(subscription);
+        });
+        if (subscriptionList.size() == 0) {
+            throw new ClientLogger(Utils.class).logExceptionAsError(
+                new IllegalStateException("Please create a subscription before you start resource management. "
+                + "To learn more, see: https://azure.microsoft.com/en-us/free/."));
+        } else if (subscriptionList.size() > 1) {
+            StringBuilder stringBuilder = new StringBuilder();
+            stringBuilder.append("More than one subscription found in your tenant. "
+                + "Please specify which one below is desired for resource management.");
+            subscriptionList.forEach(subscription -> {
+                stringBuilder.append("\n" + subscription.displayName() + " : " + subscription.subscriptionId());
+            });
+            throw new ClientLogger(Utils.class).logExceptionAsError(
+                new IllegalStateException(stringBuilder.toString()));
+        }
+        return subscriptionList.get(0).subscriptionId();
     }
 }

sdk/resources/mgmt/src/main/java/com/azure/management/resources/implementation/ResourceManager.java

@@ -5,7 +5,6 @@
 
 import com.azure.core.credential.TokenCredential;
 import com.azure.core.http.HttpPipeline;
-import com.azure.core.util.logging.ClientLogger;
 import com.azure.management.resources.Deployments;
 import com.azure.management.resources.Features;
 import com.azure.management.resources.GenericResources;
@@ -22,6 +21,7 @@
 import com.azure.management.resources.fluentcore.profile.AzureProfile;
 import com.azure.management.resources.fluentcore.utils.HttpPipelineProvider;
 import com.azure.management.resources.fluentcore.utils.SdkContext;
+import com.azure.management.resources.fluentcore.utils.Utils;
 import com.azure.management.resources.models.FeatureClientBuilder;
 import com.azure.management.resources.models.FeatureClientImpl;
 import com.azure.management.resources.models.PolicyClientBuilder;
@@ -133,8 +133,10 @@ public interface Authenticated {
         ResourceManager withSubscription(String subscriptionId);
 
         /**
-         * Specifies to use subscription from Azure profile.
+         * Specifies to use subscription from {@link AzureProfile}. If no subscription provided, we will
+         * try to set the only subscription if applicable returned by {@link Authenticated#subscriptions()}.
          *
+         * @throws IllegalStateException when no subscription or more than one subscription found in the tenant.
          * @return the ResourceManager instance with entry points that work in a subscription
          */
         ResourceManager withDefaultSubscription();
@@ -144,7 +146,6 @@ public interface Authenticated {
      * The implementation for Authenticated interface.
      */
     private static final class AuthenticatedImpl implements Authenticated {
-        private final ClientLogger logger = new ClientLogger(AuthenticatedImpl.class);
         private HttpPipeline httpPipeline;
         private AzureProfile profile;
         private SdkContext sdkContext;
@@ -192,8 +193,7 @@ public ResourceManager withSubscription(String subscriptionId) {
         @Override
         public ResourceManager withDefaultSubscription() {
             if (profile.subscriptionId() == null) {
-                throw logger.logExceptionAsError(
-                    new IllegalArgumentException("Please specify the subscription ID for resource management."));
+                profile.withSubscriptionId(Utils.defaultSubscription(this.subscriptions().list()));
             }
             return new ResourceManager(httpPipeline, profile, sdkContext);
         }