Throw errors on model deletion failures

CHANGELOG.md

@@ -17,6 +17,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Features
 ### Enhancements
 ### Bug Fixes
+* Throw errors on model deletion failures ([#834](https://github.com/opensearch-project/k-NN/pull/834))
 ### Infrastructure
 * Adding filter type to filtering release configs ([#792](https://github.com/opensearch-project/k-NN/pull/792))
 * Add CHANGELOG ([#800](https://github.com/opensearch-project/k-NN/pull/800))

qa/restart-upgrade/src/test/java/org/opensearch/knn/bwc/ModelIT.java

@@ -10,6 +10,7 @@
 import org.opensearch.action.search.SearchResponse;
 import org.opensearch.client.Request;
 import org.opensearch.client.Response;
+import org.opensearch.client.ResponseException;
 import org.opensearch.common.Strings;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.common.xcontent.XContentFactory;
@@ -20,14 +21,12 @@
 import org.opensearch.knn.indices.ModelMetadata;
 import org.opensearch.knn.indices.ModelState;
 import org.opensearch.knn.plugin.KNNPlugin;
-import org.opensearch.knn.plugin.transport.DeleteModelResponse;
 import org.opensearch.rest.RestStatus;
 import org.opensearch.search.SearchHit;
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
-import java.util.Locale;
 import java.util.Map;
 
 import static org.opensearch.knn.TestUtils.KNN_BWC_PREFIX;
@@ -44,7 +43,6 @@
 import static org.opensearch.knn.common.KNNConstants.PARAMETERS;
 import static org.opensearch.knn.common.KNNConstants.METHOD_PARAMETER_NLIST;
 import static org.opensearch.knn.common.KNNConstants.NMSLIB_NAME;
-import static org.opensearch.knn.common.KNNConstants.MODEL_INDEX_NAME;
 
 public class ModelIT extends AbstractRestartUpgradeTestCase {
     private static final String TEST_MODEL_INDEX = KNN_BWC_PREFIX + "test-model-index";
@@ -153,25 +151,8 @@ public void testDeleteTrainingModel() throws Exception {
             String restURI = String.join("/", KNNPlugin.KNN_BASE_URI, MODELS, TEST_MODEL_ID_TRAINING);
             Request request = new Request("DELETE", restURI);
 
-            Response response = client().performRequest(request);
-            assertEquals(request.getEndpoint() + ": failed", RestStatus.OK, RestStatus.fromCode(response.getStatusLine().getStatusCode()));
-
-            assertEquals(3, getDocCount(MODEL_INDEX_NAME));
-
-            String responseBody = EntityUtils.toString(response.getEntity());
-            assertNotNull(responseBody);
-
-            Map<String, Object> responseMap = createParser(XContentType.JSON.xContent(), responseBody).map();
-
-            assertEquals(TEST_MODEL_ID_TRAINING, responseMap.get(MODEL_ID));
-            assertEquals("failed", responseMap.get(DeleteModelResponse.RESULT));
-
-            String errorMessage = String.format(
-                Locale.ROOT,
-                "Cannot delete model \"%s\". Model is still in " + "training",
-                TEST_MODEL_ID_TRAINING
-            );
-            assertEquals(errorMessage, responseMap.get(DeleteModelResponse.ERROR_MSG));
+            ResponseException ex = expectThrows(ResponseException.class, () -> client().performRequest(request));
+            assertEquals(RestStatus.CONFLICT.getStatus(), ex.getResponse().getStatusLine().getStatusCode());
         }
     }
 
@@ -181,7 +162,6 @@ public static void wipeAllModels() throws IOException {
         if (!isRunningAgainstOldCluster()) {
             deleteKNNModel(TEST_MODEL_ID);
             deleteKNNModel(TEST_MODEL_ID_DEFAULT);
-            deleteKNNModel(TEST_MODEL_ID_TRAINING);
         }
     }
 

src/main/java/org/opensearch/knn/common/exception/DeleteModelWhenInTrainStateException.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.knn.common.exception;
+
+import org.opensearch.OpenSearchException;
+import org.opensearch.common.logging.LoggerMessageFormat;
+import org.opensearch.rest.RestStatus;
+
+/**
+ * Exception thrown when a model is deleted while it is in the training state. The RestStatus associated with this
+ * exception should be a {@link RestStatus#CONFLICT} because the request cannot be deleted due to the model being in
+ * the training state.
+ */
+public class DeleteModelWhenInTrainStateException extends OpenSearchException {
+    /**
+     * Constructor
+     *
+     * @param msg detailed exception message
+     * @param args arguments of the message
+     */
+    public DeleteModelWhenInTrainStateException(String msg, Object... args) {
+        super(LoggerMessageFormat.format(msg, args));
+    }
+
+    @Override
+    public RestStatus status() {
+        return RestStatus.CONFLICT;
+    }
+}

src/main/java/org/opensearch/knn/indices/ModelDao.java

@@ -45,6 +45,7 @@
 import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.knn.common.KNNConstants;
 import org.opensearch.knn.common.ThreadContextHelper;
+import org.opensearch.knn.common.exception.DeleteModelWhenInTrainStateException;
 import org.opensearch.knn.plugin.transport.DeleteModelResponse;
 import org.opensearch.knn.plugin.transport.GetModelResponse;
 import org.opensearch.knn.plugin.transport.RemoveModelFromCacheAction;
@@ -174,8 +175,6 @@ public interface ModelDao {
     final class OpenSearchKNNModelDao implements ModelDao {
 
         public static Logger logger = LogManager.getLogger(ModelDao.class);
-        private static final String DELETED = "deleted";
-        private static final String FAILED = "failed";
 
         private int numberOfShards;
         private int numberOfReplicas;
@@ -487,9 +486,8 @@ public boolean isModelInGraveyard(String modelId) {
         public void delete(String modelId, ActionListener<DeleteModelResponse> listener) {
             // If the index is not created, there is no need to delete the model
             if (!isCreated()) {
-                logger.error("Cannot delete model \"" + modelId + "\". Model index " + MODEL_INDEX_NAME + "does not exist.");
-                String errorMessage = String.format("Cannot delete model \"%s\". Model index does not exist", modelId);
-                listener.onResponse(new DeleteModelResponse(modelId, FAILED, errorMessage));
+                String errorMessage = String.format("Cannot delete model [%s]. Model index [%s] does not exist", modelId, MODEL_INDEX_NAME);
+                listener.onFailure(new ResourceNotFoundException(errorMessage));
                 return;
             }
 
@@ -503,7 +501,7 @@ public void delete(String modelId, ActionListener<DeleteModelResponse> listener)
             // Get Model to check if model is in TRAINING
             get(modelId, ActionListener.wrap(getModelStep::onResponse, exception -> {
                 if (exception instanceof ResourceNotFoundException) {
-                    String errorMessage = String.format("Unable to delete model \"%s\". Model does not exist", modelId);
+                    String errorMessage = String.format("Unable to delete model [%s]. Model does not exist", modelId);
                     ResourceNotFoundException resourceNotFoundException = new ResourceNotFoundException(errorMessage);
                     removeModelIdFromGraveyardOnFailure(modelId, resourceNotFoundException, getModelStep);
                 } else {
@@ -514,8 +512,8 @@ public void delete(String modelId, ActionListener<DeleteModelResponse> listener)
             getModelStep.whenComplete(getModelResponse -> {
                 // If model is in Training state, fail delete model request
                 if (ModelState.TRAINING == getModelResponse.getModel().getModelMetadata().getState()) {
-                    String errorMessage = String.format("Cannot delete model \"%s\". Model is still in training", modelId);
-                    listener.onResponse(new DeleteModelResponse(modelId, FAILED, errorMessage));
+                    String errorMessage = String.format("Cannot delete model [%s]. Model is still in training", modelId);
+                    listener.onFailure(new DeleteModelWhenInTrainStateException(errorMessage));
                     return;
                 }
 
@@ -544,8 +542,8 @@ public void delete(String modelId, ActionListener<DeleteModelResponse> listener)
                 // If model is not deleted, remove modelId from model graveyard and return with error message
                 if (deleteResponse.getResult() != DocWriteResponse.Result.DELETED) {
                     updateModelGraveyardToDelete(modelId, true, unblockModelIdStep, Optional.empty());
-                    String errorMessage = String.format("Model \" %s \" does not exist", modelId);
-                    listener.onResponse(new DeleteModelResponse(modelId, deleteResponse.getResult().getLowercase(), errorMessage));
+                    String errorMessage = String.format("Model [%s] does not exist", modelId);
+                    listener.onFailure(new ResourceNotFoundException(errorMessage));
                     return;
                 }
 
@@ -569,7 +567,7 @@ public void delete(String modelId, ActionListener<DeleteModelResponse> listener)
 
             unblockModelIdStep.whenComplete(acknowledgedResponse -> {
                 // After clearing the cache, if there are no errors return the response
-                listener.onResponse(new DeleteModelResponse(modelId, DELETED, null));
+                listener.onResponse(new DeleteModelResponse(modelId));
 
             }, listener::onFailure);
 

src/main/java/org/opensearch/knn/plugin/transport/DeleteModelResponse.java

@@ -12,7 +12,6 @@
 
 import org.opensearch.action.ActionResponse;
 import org.opensearch.common.Nullable;
-import org.opensearch.common.Strings;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.core.xcontent.ToXContentObject;
@@ -29,16 +28,40 @@ public class DeleteModelResponse extends ActionResponse implements ToXContentObj
 
     public static final String RESULT = "result";
     public static final String ERROR_MSG = "error";
+    private static final String DELETED = "deleted";
     private final String modelID;
     private final String result;
     private final String errorMessage;
 
+    /**
+     * Ctor to build delete model response.
+     * @deprecated
+     * Returning errors through {@link DeleteModelResponse} should not be done. Instead, if there is an
+     * error, throw/return a suitable exception. Use {@link DeleteModelResponse#DeleteModelResponse(String)} to
+     * construct valid responses instead.
+     *
+     * @param modelID ID of the model that is deleted
+     * @param result Resulting action of the deletion.
+     * @param errorMessage Error message to be returned to the user
+     */
+    @Deprecated
     public DeleteModelResponse(String modelID, String result, @Nullable String errorMessage) {
         this.modelID = modelID;
         this.result = result;
         this.errorMessage = errorMessage;
     }
 
+    /**
+     * Ctor to build delete model response
+     *
+     * @param modelID ID of the model that is deleted
+     */
+    public DeleteModelResponse(String modelID) {
+        this.modelID = modelID;
+        this.result = DELETED;
+        this.errorMessage = null;
+    }
+
     public DeleteModelResponse(StreamInput in) throws IOException {
         super(in);
         this.modelID = in.readString();
@@ -63,16 +86,12 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         /* Response should look like below:
             {
                 "model_id": "my_model_id"
-                "result": "not_found",
-                "error": "Model my_model_id doesn't exist"
+                "result": "deleted"
         }
          */
         builder.startObject();
         builder.field(MODEL_ID, getModelID());
         builder.field(RESULT, getResult());
-        if (Strings.hasText(errorMessage)) {
-            builder.field(ERROR_MSG, getErrorMessage());
-        }
         builder.endObject();
         return builder;
 

src/main/java/org/opensearch/knn/plugin/transport/DeleteModelTransportAction.java

@@ -11,6 +11,7 @@
 
 package org.opensearch.knn.plugin.transport;
 
+import lombok.extern.log4j.Log4j2;
 import org.opensearch.action.ActionListener;
 import org.opensearch.action.support.ActionFilters;
 import org.opensearch.action.support.HandledTransportAction;
@@ -21,6 +22,7 @@
 import org.opensearch.tasks.Task;
 import org.opensearch.transport.TransportService;
 
+@Log4j2
 public class DeleteModelTransportAction extends HandledTransportAction<DeleteModelRequest, DeleteModelResponse> {
 
     private final ModelDao modelDao;
@@ -37,7 +39,10 @@ public DeleteModelTransportAction(TransportService transportService, ActionFilte
     protected void doExecute(Task task, DeleteModelRequest request, ActionListener<DeleteModelResponse> listener) {
         ThreadContextHelper.runWithStashedThreadContext(client, () -> {
             String modelID = request.getModelID();
-            modelDao.delete(modelID, listener);
+            modelDao.delete(modelID, ActionListener.wrap(listener::onResponse, e -> {
+                log.error(e);
+                listener.onFailure(e);
+            }));
         });
     }
 }

src/test/java/org/opensearch/knn/indices/ModelDaoTests.java

@@ -16,6 +16,7 @@
 import org.junit.BeforeClass;
 import org.opensearch.ExceptionsHelper;
 import org.opensearch.ResourceAlreadyExistsException;
+import org.opensearch.ResourceNotFoundException;
 import org.opensearch.action.ActionListener;
 import org.opensearch.action.DocWriteResponse;
 import org.opensearch.action.StepListener;
@@ -32,6 +33,7 @@
 import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.index.engine.VersionConflictEngineException;
 import org.opensearch.knn.KNNSingleNodeTestCase;
+import org.opensearch.knn.common.exception.DeleteModelWhenInTrainStateException;
 import org.opensearch.knn.index.SpaceType;
 import org.opensearch.knn.index.util.KNNEngine;
 import org.opensearch.knn.plugin.transport.DeleteModelResponse;
@@ -500,10 +502,13 @@ public void testDelete() throws IOException, InterruptedException {
         int dimension = 2;
 
         final CountDownLatch inProgressLatch = new CountDownLatch(1);
-        ActionListener<DeleteModelResponse> deleteModelIndexDoesNotExistListener = ActionListener.wrap(response -> {
-            assertEquals(FAILED, response.getResult());
-            inProgressLatch.countDown();
-        }, exception -> fail("Unable to delete the model: " + exception));
+        ActionListener<DeleteModelResponse> deleteModelIndexDoesNotExistListener = ActionListener.wrap(
+            response -> fail("Deleting model when model index does not exist should throw ResourceNotFoundException"),
+            exception -> {
+                assertTrue(exception instanceof ResourceNotFoundException);
+                inProgressLatch.countDown();
+            }
+        );
         // model index doesnt exist
         modelDao.delete(modelId, deleteModelIndexDoesNotExistListener);
         assertTrue(inProgressLatch.await(100, TimeUnit.SECONDS));
@@ -512,25 +517,27 @@ public void testDelete() throws IOException, InterruptedException {
 
         // Model does not exist
         final CountDownLatch inProgressLatch1 = new CountDownLatch(1);
-        ActionListener<DeleteModelResponse> deleteModelDoesNotExistListener = ActionListener.wrap(Assert::assertNull, exception -> {
-            assertNotNull(exception);
-            assertTrue(exception.getMessage().contains(modelId));
-            assertTrue(exception.getMessage().contains("Model does not exist"));
-            assertFalse(modelDao.isModelInGraveyard(modelId));
-            inProgressLatch1.countDown();
-        });
+        ActionListener<DeleteModelResponse> deleteModelDoesNotExistListener = ActionListener.wrap(
+            response -> fail("Deleting model when model does not exist should throw ResourceNotFoundException"),
+            exception -> {
+                assertTrue(exception instanceof ResourceNotFoundException);
+                assertFalse(modelDao.isModelInGraveyard(modelId));
+                inProgressLatch1.countDown();
+            }
+        );
 
         modelDao.delete(modelId, deleteModelDoesNotExistListener);
         assertTrue(inProgressLatch1.await(60, TimeUnit.SECONDS));
 
         final CountDownLatch inProgressLatch2 = new CountDownLatch(1);
-        ActionListener<DeleteModelResponse> deleteModelTrainingListener = ActionListener.wrap(response -> {
-            assertEquals(modelId, response.getModelID());
-            assertEquals(FAILED, response.getResult());
-            String errorMessage = String.format("Cannot delete model \"%s\". Model is still in training", modelId);
-            assertEquals(errorMessage, response.getErrorMessage());
-            inProgressLatch2.countDown();
-        }, exception -> fail("Unable to delete model: " + exception));
+        ActionListener<DeleteModelResponse> deleteModelTrainingListener = ActionListener.wrap(
+            response -> fail("Deleting model when model does not exist should throw ResourceNotFoundException"),
+            exception -> {
+                assertTrue(exception instanceof DeleteModelWhenInTrainStateException);
+                assertFalse(modelDao.isModelInGraveyard(modelId));
+                inProgressLatch2.countDown();
+            }
+        );
 
         // model id exists and model is still in Training
         Model model = new Model(

src/test/java/org/opensearch/knn/plugin/action/RestDeleteModelHandlerIT.java

@@ -20,7 +20,6 @@
 import org.opensearch.common.xcontent.XContentType;
 import org.opensearch.knn.KNNRestTestCase;
 import org.opensearch.knn.plugin.KNNPlugin;
-import org.opensearch.knn.plugin.transport.DeleteModelResponse;
 import org.opensearch.rest.RestStatus;
 
 import java.util.List;
@@ -107,23 +106,8 @@ public void testDeleteTrainingModel() throws Exception {
         String deleteModelRestURI = String.join("/", KNNPlugin.KNN_BASE_URI, MODELS, modelId);
         Request deleteModelRequest = new Request("DELETE", deleteModelRestURI);
 
-        Response deleteModelResponse = client().performRequest(deleteModelRequest);
-        assertEquals(
-            deleteModelRequest.getEndpoint() + ": failed",
-            RestStatus.OK,
-            RestStatus.fromCode(deleteModelResponse.getStatusLine().getStatusCode())
-        );
-
-        responseBody = EntityUtils.toString(deleteModelResponse.getEntity());
-        assertNotNull(responseBody);
-
-        responseMap = createParser(XContentType.JSON.xContent(), responseBody).map();
-
-        assertEquals(modelId, responseMap.get(MODEL_ID));
-        assertEquals("failed", responseMap.get(DeleteModelResponse.RESULT));
-
-        String errorMessage = String.format("Cannot delete model \"%s\". Model is still in training", modelId);
-        assertEquals(errorMessage, responseMap.get(DeleteModelResponse.ERROR_MSG));
+        ResponseException ex = expectThrows(ResponseException.class, () -> client().performRequest(deleteModelRequest));
+        assertEquals(RestStatus.CONFLICT.getStatus(), ex.getResponse().getStatusLine().getStatusCode());
 
         // need to wait for training operation as it's required for after test cleanup
         assertTrainingSucceeds(modelId, NUM_OF_ATTEMPTS, DELAY_MILLI_SEC);
@@ -136,7 +120,7 @@ public void testDeleteModelFailsInvalid() throws Exception {
         Request request = new Request("DELETE", restURI);
 
         ResponseException ex = expectThrows(ResponseException.class, () -> client().performRequest(request));
-        assertTrue(ex.getMessage().contains(modelId));
+        assertEquals(RestStatus.NOT_FOUND.getStatus(), ex.getResponse().getStatusLine().getStatusCode());
     }
 
     // Test Train Model -> Delete Model -> Train Model with same modelId