Resources: fix NPE when trying to get non-existing resource (#1098)

* Resources: fix NPE when trying to get non-existing resource

* Resources: support api version when listing generic resources

azure-mgmt-resources/src/main/java/com/microsoft/azure/management/resources/implementation/GenericResourceImpl.java

@@ -63,6 +63,9 @@ final class GenericResourceImpl
 
     @Override
     public String apiVersion() {
+        if (apiVersion == null) {
+            apiVersion = ResourceUtils.defaultApiVersion(id(), manager().providers().getByName(ResourceUtils.resourceProviderFromResourceId(id())));
+        }
         return apiVersion;
     }
 

azure-mgmt-resources/src/main/java/com/microsoft/azure/management/resources/implementation/GenericResourcesImpl.java

@@ -90,7 +90,8 @@ final class GenericResourcesImpl
     public GenericResource getById(String id) {
         Provider provider = this.manager().providers().getByName(ResourceUtils.resourceProviderFromResourceId(id));
         String apiVersion = ResourceUtils.defaultApiVersion(id, provider);
-        return wrapModel(this.inner().getById(id, apiVersion)).withApiVersion(apiVersion);
+        GenericResourceImpl genericResource = wrapModel(this.inner().getById(id, apiVersion));
+        return genericResource == null ? null : genericResource.withApiVersion(apiVersion);
     }
 
     @Override
@@ -132,6 +133,11 @@ final class GenericResourcesImpl
                 resourceType,
                 resourceName,
                 apiVersion);
+
+        if (inner == null) {
+            return null;
+        }
+
         GenericResourceImpl resource = new GenericResourceImpl(
                 resourceName,
                 inner,

azure-mgmt-resources/src/test/java/com/microsoft/azure/management/resources/GenericResourcesTests.java

@@ -66,6 +66,7 @@ public class GenericResourcesTests extends ResourceManagerTestBase {
         boolean found = false;
         for (GenericResource gr: resourceList) {
             if (gr.name().equals(resource.name())) {
+                Assert.assertNotNull(gr.apiVersion());
                 found = true;
                 break;
             }