Bugfix by moving onResponse call into the new action listener; also add new test to catch this bug (#113898)

Author: maxhniebergall

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/services/elser/ElserInternalService.java

@@ -101,17 +101,16 @@ public void parseRequestConfig(
                     serviceSettingsBuilder.setModelId(
                         selectDefaultModelVariantBasedOnClusterArchitecture(arch, ELSER_V2_MODEL_LINUX_X86, ELSER_V2_MODEL)
                     );
+                    parsedModelListener.onResponse(
+                        new ElserInternalModel(
+                            inferenceEntityId,
+                            taskType,
+                            NAME,
+                            new ElserInternalServiceSettings(serviceSettingsBuilder.build()),
+                            taskSettings
+                        )
+                    );
                 }));
-
-                parsedModelListener.onResponse(
-                    new ElserInternalModel(
-                        inferenceEntityId,
-                        taskType,
-                        NAME,
-                        new ElserInternalServiceSettings(serviceSettingsBuilder.build()),
-                        taskSettings
-                    )
-                );
             } else {
                 parsedModelListener.onResponse(
                     new ElserInternalModel(

x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/elser/ElserInternalServiceTests.java

@@ -120,6 +120,31 @@ public void testParseConfigStrict() {
 
     }
 
+    public void testParseConfigWithoutModelId() {
+        Client mockClient = mock(Client.class);
+        when(mockClient.threadPool()).thenReturn(threadPool);
+        var service = createService(mockClient);
+
+        var settings = new HashMap<String, Object>();
+        settings.put(
+            ModelConfigurations.SERVICE_SETTINGS,
+            new HashMap<>(Map.of(ElserInternalServiceSettings.NUM_ALLOCATIONS, 1, ElserInternalServiceSettings.NUM_THREADS, 4))
+        );
+
+        var expectedModel = new ElserInternalModel(
+            "foo",
+            TaskType.SPARSE_EMBEDDING,
+            ElserInternalService.NAME,
+            new ElserInternalServiceSettings(1, 4, ".elser_model_2", null),
+            ElserMlNodeTaskSettings.DEFAULT
+        );
+
+        var modelVerificationListener = getModelVerificationListener(expectedModel);
+
+        service.parseRequestConfig("foo", TaskType.SPARSE_EMBEDDING, settings, modelVerificationListener);
+
+    }
+
     public void testParseConfigLooseWithOldModelId() {
         var service = createService(mock(Client.class));