[Transform] Improve force stop robustness in case of an error (#51072)

If a transform config got lost (e.g. because the internal index disappeared) tasks could not be
stopped using transform API. This change makes it possible to stop transforms without a config,
meaning to remove the background task. In order to do so force must be set to true.

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/transform/TransformMessages.java

@@ -17,6 +17,8 @@ public class TransformMessages {
             "Interrupted while waiting for transform [{0}] to stop";
     public static final String REST_PUT_TRANSFORM_EXISTS = "Transform with id [{0}] already exists";
     public static final String REST_UNKNOWN_TRANSFORM = "Transform with id [{0}] could not be found";
+    public static final String REST_STOP_TRANSFORM_WITHOUT_CONFIG =
+            "Detected transforms with no config [{0}]. Use force to stop/delete them.";
     public static final String REST_PUT_TRANSFORM_FAILED_TO_VALIDATE_CONFIGURATION =
             "Failed to validate configuration";
     public static final String REST_PUT_FAILED_PERSIST_TRANSFORM_CONFIGURATION = "Failed to persist transform configuration";

x-pack/plugin/transform/qa/single-node-tests/src/test/java/org/elasticsearch/xpack/transform/integration/TransformPivotRestIT.java

@@ -918,12 +918,4 @@ public class TransformPivotRestIT extends TransformRestTestCase {
         assertOnePivotValue(dataFrameIndex + "/_search?q=reviewer:user_26", 3.918918918);
         deleteIndex(indexName);
     }
-
-    private void assertOnePivotValue(String query, double expected) throws IOException {
-        Map<String, Object> searchResult = getAsMap(query);
-
-        assertEquals(1, XContentMapValues.extractValue("hits.total.value", searchResult));
-        double actual = (Double) ((List<?>) XContentMapValues.extractValue("hits.hits._source.avg_rating", searchResult)).get(0);
-        assertEquals(expected, actual, 0.000001);
-    }
 }

x-pack/plugin/transform/qa/single-node-tests/src/test/java/org/elasticsearch/xpack/transform/integration/TransformRestTestCase.java

@@ -158,6 +158,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         bulkRequest.setJsonEntity(bulk.toString());
         client().performRequest(bulkRequest);
     }
+
     /**
      * Create a simple dataset for testing with reviewers, ratings and businesses
      */
@@ -182,8 +183,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
 
         final Request createDataframeTransformRequest = createRequestWithAuth("PUT", getTransformEndpoint() + transformId, authHeader);
 
-        String config = "{ \"dest\": {\"index\":\"" + dataFrameIndex + "\"},"
+        String config = "{ \"dest\": {\"index\":\"" + dataFrameIndex + "\"}," + " \"source\": {\"index\":\"" + REVIEWS_INDEX_NAME + "\"},"
-            + " \"source\": {\"index\":\"" + REVIEWS_INDEX_NAME + "\"},"
         // Set frequency high for testing
             + " \"sync\": {\"time\":{\"field\": \"timestamp\", \"delay\": \"15m\"}},"
             + " \"frequency\": \"1s\","
@@ -206,7 +206,6 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         assertThat(createDataframeTransformResponse.get("acknowledged"), equalTo(Boolean.TRUE));
     }
 
-
     protected void createPivotReviewsTransform(String transformId, String dataFrameIndex, String query, String pipeline, String authHeader)
         throws IOException {
         final Request createDataframeTransformRequest = createRequestWithAuth("PUT", getTransformEndpoint() + transformId, authHeader);
@@ -245,11 +244,11 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         assertThat(createDataframeTransformResponse.get("acknowledged"), equalTo(Boolean.TRUE));
     }
 
-    protected void startDataframeTransform(String transformId) throws IOException {
+    protected void startTransform(String transformId) throws IOException {
-        startDataframeTransform(transformId, null);
+        startTransform(transformId, null);
     }
 
-    protected void startDataframeTransform(String transformId, String authHeader, String... warnings) throws IOException {
+    protected void startTransform(String transformId, String authHeader, String... warnings) throws IOException {
         // start the transform
         final Request startTransformRequest = createRequestWithAuth("POST", getTransformEndpoint() + transformId + "/_start", authHeader);
         if (warnings.length > 0) {
@@ -280,10 +279,10 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         startAndWaitForTransform(transformId, dataFrameIndex, authHeader, new String[0]);
     }
 
-    protected void startAndWaitForTransform(String transformId, String dataFrameIndex,
+    protected void startAndWaitForTransform(String transformId, String dataFrameIndex, String authHeader, String... warnings)
-                                            String authHeader, String... warnings) throws Exception {
+        throws Exception {
         // start the transform
-        startDataframeTransform(transformId, authHeader, warnings);
+        startTransform(transformId, authHeader, warnings);
         assertTrue(indexExists(dataFrameIndex));
         // wait until the dataframe has been created and all data is available
         waitForDataFrameCheckpoint(transformId);
@@ -292,18 +291,14 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         refreshIndex(dataFrameIndex);
     }
 
-    protected void startAndWaitForContinuousTransform(String transformId,
+    protected void startAndWaitForContinuousTransform(String transformId, String dataFrameIndex, String authHeader) throws Exception {
-                                                      String dataFrameIndex,
-                                                      String authHeader) throws Exception {
         startAndWaitForContinuousTransform(transformId, dataFrameIndex, authHeader, 1L);
     }
 
-    protected void startAndWaitForContinuousTransform(String transformId,
+    protected void startAndWaitForContinuousTransform(String transformId, String dataFrameIndex, String authHeader, long checkpoint)
-                                                      String dataFrameIndex,
+        throws Exception {
-                                                      String authHeader,
-                                                      long checkpoint) throws Exception {
         // start the transform
-        startDataframeTransform(transformId, authHeader, new String[0]);
+        startTransform(transformId, authHeader, new String[0]);
         assertTrue(indexExists(dataFrameIndex));
         // wait until the dataframe has been created and all data is available
         waitForTransformCheckpoint(transformId, checkpoint);
@@ -323,9 +318,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
     }
 
     void waitForDataFrameStopped(String transformId) throws Exception {
-        assertBusy(() -> {
+        assertBusy(() -> { assertEquals("stopped", getTransformState(transformId)); }, 15, TimeUnit.SECONDS);
-            assertEquals("stopped", getDataFrameTransformState(transformId));
-        }, 15, TimeUnit.SECONDS);
     }
 
     void waitForDataFrameCheckpoint(String transformId) throws Exception {
@@ -341,7 +334,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
     }
 
     @SuppressWarnings("unchecked")
-    private static List<Map<String, Object>> getDataFrameTransforms() throws IOException {
+    protected static List<Map<String, Object>> getTransforms() throws IOException {
         Response response = adminClient().performRequest(new Request("GET", getTransformEndpoint() + "_all"));
         Map<String, Object> transforms = entityAsMap(response);
         List<Map<String, Object>> transformConfigs = (List<Map<String, Object>>) XContentMapValues.extractValue("transforms", transforms);
@@ -349,12 +342,12 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         return transformConfigs == null ? Collections.emptyList() : transformConfigs;
     }
 
-    protected static String getDataFrameTransformState(String transformId) throws IOException {
+    protected static String getTransformState(String transformId) throws IOException {
-        Map<?, ?> transformStatsAsMap = getDataFrameState(transformId);
+        Map<?, ?> transformStatsAsMap = getTransformStateAndStats(transformId);
         return transformStatsAsMap == null ? null : (String) XContentMapValues.extractValue("state", transformStatsAsMap);
     }
 
-    protected static Map<?, ?> getDataFrameState(String transformId) throws IOException {
+    protected static Map<?, ?> getTransformStateAndStats(String transformId) throws IOException {
         Response statsResponse = client().performRequest(new Request("GET", getTransformEndpoint() + transformId + "/_stats"));
         List<?> transforms = ((List<?>) entityAsMap(statsResponse).get("transforms"));
         if (transforms.isEmpty()) {
@@ -383,7 +376,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
     }
 
     public void wipeTransforms() throws IOException {
-        List<Map<String, Object>> transformConfigs = getDataFrameTransforms();
+        List<Map<String, Object>> transformConfigs = getTransforms();
         for (Map<String, Object> transformConfig : transformConfigs) {
             String transformId = (String) transformConfig.get("id");
             Request request = new Request("POST", getTransformEndpoint() + transformId + "/_stop");
@@ -395,7 +388,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
 
         for (Map<String, Object> transformConfig : transformConfigs) {
             String transformId = (String) transformConfig.get("id");
-            String state = getDataFrameTransformState(transformId);
+            String state = getTransformState(transformId);
             assertEquals("Transform [" + transformId + "] is not in the stopped state", "stopped", state);
         }
 
@@ -405,7 +398,7 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
         }
 
         // transforms should be all gone
-        transformConfigs = getDataFrameTransforms();
+        transformConfigs = getTransforms();
         assertTrue(transformConfigs.isEmpty());
 
         // the configuration index should be empty
@@ -437,11 +430,15 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
     protected void setupDataAccessRole(String role, String... indices) throws IOException {
         String indicesStr = Arrays.stream(indices).collect(Collectors.joining("\",\"", "\"", "\""));
         Request request = new Request("PUT", "/_security/role/" + role);
-        request.setJsonEntity("{"
+        request.setJsonEntity(
+            "{"
                 + "  \"indices\" : ["
-            + "    { \"names\": [" + indicesStr + "], \"privileges\": [\"create_index\", \"read\", \"write\", \"view_index_metadata\"] }"
+                + "    { \"names\": ["
+                + indicesStr
+                + "], \"privileges\": [\"create_index\", \"read\", \"write\", \"view_index_metadata\"] }"
                 + "  ]"
-            + "}");
+                + "}"
+        );
         client().performRequest(request);
     }
 
@@ -450,13 +447,18 @@ public abstract class TransformRestTestCase extends ESRestTestCase {
 
         String rolesStr = roles.stream().collect(Collectors.joining("\",\"", "\"", "\""));
         Request request = new Request("PUT", "/_security/user/" + user);
-        request.setJsonEntity("{"
+        request.setJsonEntity("{" + "  \"password\" : \"" + password + "\"," + "  \"roles\" : [ " + rolesStr + " ]" + "}");
-            + "  \"password\" : \"" + password + "\","
-            + "  \"roles\" : [ " + rolesStr + " ]"
-            + "}");
         client().performRequest(request);
     }
 
+    protected void assertOnePivotValue(String query, double expected) throws IOException {
+        Map<String, Object> searchResult = getAsMap(query);
+
+        assertEquals(1, XContentMapValues.extractValue("hits.total.value", searchResult));
+        double actual = (Double) ((List<?>) XContentMapValues.extractValue("hits.hits._source.avg_rating", searchResult)).get(0);
+        assertEquals(expected, actual, 0.000001);
+    }
+
     protected static String getTransformEndpoint() {
         return useDeprecatedEndpoints ? TransformField.REST_BASE_PATH_TRANSFORMS_DEPRECATED : TransformField.REST_BASE_PATH_TRANSFORMS;
     }

x-pack/plugin/transform/qa/single-node-tests/src/test/java/org/elasticsearch/xpack/transform/integration/TransformRobustnessIT.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+package org.elasticsearch.xpack.transform.integration;
+
+import org.elasticsearch.client.Request;
+import org.elasticsearch.client.ResponseException;
+import org.elasticsearch.xpack.core.transform.TransformField;
+import org.elasticsearch.xpack.core.transform.transforms.persistence.TransformInternalIndexConstants;
+
+import java.io.IOException;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalTo;
+
+public class TransformRobustnessIT extends TransformRestTestCase {
+
+    public void testTaskRemovalAfterInternalIndexGotDeleted() throws Exception {
+        String indexName = "continuous_reviews";
+        createReviewsIndex(indexName);
+        String transformId = "simple_continuous_pivot";
+        String transformIndex = "pivot_reviews_continuous";
+        final Request createTransformRequest = new Request("PUT", TransformField.REST_BASE_PATH_TRANSFORMS + transformId);
+        String config = "{"
+            + " \"source\": {\"index\":\""
+            + indexName
+            + "\"},"
+            + " \"dest\": {\"index\":\""
+            + transformIndex
+            + "\"},"
+            + " \"frequency\": \"1s\","
+            + " \"sync\": {\"time\": {\"field\": \"timestamp\", \"delay\": \"1s\"}},"
+            + " \"pivot\": {"
+            + "   \"group_by\": {"
+            + "     \"reviewer\": {"
+            + "       \"terms\": {"
+            + "         \"field\": \"user_id\""
+            + " } } },"
+            + "   \"aggregations\": {"
+            + "     \"avg_rating\": {"
+            + "       \"avg\": {"
+            + "         \"field\": \"stars\""
+            + " } } } }"
+            + "}";
+        createTransformRequest.setJsonEntity(config);
+        Map<String, Object> createTransformResponse = entityAsMap(client().performRequest(createTransformRequest));
+        assertThat(createTransformResponse.get("acknowledged"), equalTo(Boolean.TRUE));
+        assertEquals(1, getTransforms().size());
+        // there shouldn't be a task yet
+        assertEquals(0, getNumberOfTransformTasks());
+        startAndWaitForContinuousTransform(transformId, transformIndex, null);
+        assertTrue(indexExists(transformIndex));
+
+        // a task exists
+        assertEquals(1, getNumberOfTransformTasks());
+        // get and check some users
+        assertOnePivotValue(transformIndex + "/_search?q=reviewer:user_0", 3.776978417);
+        assertOnePivotValue(transformIndex + "/_search?q=reviewer:user_5", 3.72);
+        assertNotNull(getTransformState(transformId));
+
+        assertEquals(1, getTransforms().size());
+
+        // delete the transform index
+        beEvilAndDeleteTheTransformIndex();
+        // transform is gone
+        assertEquals(0, getTransforms().size());
+        // but the task is still there
+        assertEquals(1, getNumberOfTransformTasks());
+
+        Request stopTransformRequest = new Request("POST", TransformField.REST_BASE_PATH_TRANSFORMS + transformId + "/_stop");
+        ResponseException e = expectThrows(ResponseException.class, () -> client().performRequest(stopTransformRequest));
+
+        assertEquals(409, e.getResponse().getStatusLine().getStatusCode());
+        assertThat(
+            e.getMessage(),
+            containsString("Detected transforms with no config [" + transformId + "]. Use force to stop/delete them.")
+        );
+        stopTransformRequest.addParameter(TransformField.FORCE.getPreferredName(), Boolean.toString(true));
+        Map<String, Object> stopTransformResponse = entityAsMap(client().performRequest(stopTransformRequest));
+        assertThat(stopTransformResponse.get("acknowledged"), equalTo(Boolean.TRUE));
+
+        // the task is gone
+        assertEquals(1, getNumberOfTransformTasks());
+    }
+
+    @SuppressWarnings("unchecked")
+    private int getNumberOfTransformTasks() throws IOException {
+        final Request tasksRequest = new Request("GET", "/_tasks");
+        tasksRequest.addParameter("actions", TransformField.TASK_NAME + "*");
+        Map<String, Object> tasksResponse = entityAsMap(client().performRequest(tasksRequest));
+
+        Map<String, Object> nodes = (Map<String, Object>) tasksResponse.get("nodes");
+        if (nodes == null) {
+            return 0;
+        }
+
+        int foundTasks = 0;
+        for (Entry<String, Object> node : nodes.entrySet()) {
+            Map<String, Object> nodeInfo = (Map<String, Object>) node.getValue();
+            Map<String, Object> tasks = (Map<String, Object>) nodeInfo.get("tasks");
+            foundTasks += tasks != null ? tasks.size() : 0;
+        }
+
+        return foundTasks;
+    }
+
+    private void beEvilAndDeleteTheTransformIndex() throws IOException {
+        adminClient().performRequest(new Request("DELETE", TransformInternalIndexConstants.LATEST_INDEX_NAME));
+    }
+}

x-pack/plugin/transform/qa/single-node-tests/src/test/java/org/elasticsearch/xpack/transform/integration/TransformTaskFailedStateIT.java

@@ -40,8 +40,7 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
         // Set logging level to trace
         // see: https://github.com/elastic/elasticsearch/issues/45562
         Request addFailureRetrySetting = new Request("PUT", "/_cluster/settings");
-        addFailureRetrySetting
+        addFailureRetrySetting.setJsonEntity(
-            .setJsonEntity(
             "{\"transient\": {\"xpack.transform.num_transform_failure_retries\": \""
                 + 0
                 + "\","
@@ -70,9 +69,9 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
         createDestinationIndexWithBadMapping(transformIndex);
         createContinuousPivotReviewsTransform(transformId, transformIndex, null);
         failureTransforms.add(transformId);
-        startDataframeTransform(transformId);
+        startTransform(transformId);
         awaitState(transformId, TransformStats.State.FAILED);
-        Map<?, ?> fullState = getDataFrameState(transformId);
+        Map<?, ?> fullState = getTransformStateAndStats(transformId);
         final String failureReason = "task encountered more than 0 failures; latest failure: "
             + ".*BulkIndexingException: Bulk index experienced failures. See the logs of the node running the transform for details.";
         // Verify we have failed for the expected reason
@@ -94,7 +93,7 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
         stopTransform(transformId, true);
 
         awaitState(transformId, TransformStats.State.STOPPED);
-        fullState = getDataFrameState(transformId);
+        fullState = getTransformStateAndStats(transformId);
         assertThat(XContentMapValues.extractValue("reason", fullState), is(nullValue()));
     }
 
@@ -105,9 +104,9 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
         createDestinationIndexWithBadMapping(dataFrameIndex);
         createContinuousPivotReviewsTransform(transformId, dataFrameIndex, null);
         failureTransforms.add(transformId);
-        startDataframeTransform(transformId);
+        startTransform(transformId);
         awaitState(transformId, TransformStats.State.FAILED);
-        Map<?, ?> fullState = getDataFrameState(transformId);
+        Map<?, ?> fullState = getTransformStateAndStats(transformId);
         final String failureReason = "task encountered more than 0 failures; latest failure: "
             + ".*BulkIndexingException: Bulk index experienced failures. See the logs of the node running the transform for details.";
         // Verify we have failed for the expected reason
@@ -119,7 +118,7 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
             + "\\]. Use force stop and then restart the transform once error is resolved.";
         // Verify that we cannot start the transform when the task is in a failed state
         assertBusy(() -> {
-            ResponseException ex = expectThrows(ResponseException.class, () -> startDataframeTransform(transformId));
+            ResponseException ex = expectThrows(ResponseException.class, () -> startTransform(transformId));
             assertThat(ex.getResponse().getStatusLine().getStatusCode(), equalTo(RestStatus.CONFLICT.getStatus()));
             assertThat(
                 (String) XContentMapValues.extractValue("error.reason", entityAsMap(ex.getResponse())),
@@ -132,7 +131,7 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
 
     private void awaitState(String transformId, TransformStats.State state) throws Exception {
         assertBusy(() -> {
-            String currentState = getDataFrameTransformState(transformId);
+            String currentState = getTransformState(transformId);
             assertThat(currentState, equalTo(state.value()));
         }, 180, TimeUnit.SECONDS); // It should not take this long, but if the scheduler gets deferred, it could
     }
@@ -142,8 +141,7 @@ public class TransformTaskFailedStateIT extends TransformRestTestCase {
         try (XContentBuilder builder = jsonBuilder()) {
             builder.startObject();
             {
-                builder
+                builder.startObject("mappings")
-                    .startObject("mappings")
                     .startObject("properties")
                     .startObject("reviewer")
                     .field("type", "long")

x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/action/TransportStopTransformAction.java

@@ -9,6 +9,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.ElasticsearchStatusException;
+import org.elasticsearch.ResourceNotFoundException;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.ActionListenerResponseHandler;
 import org.elasticsearch.action.FailedNodeException;
@@ -19,22 +20,28 @@ import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
 import org.elasticsearch.cluster.service.ClusterService;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.logging.LoggerMessageFormat;
+import org.elasticsearch.common.regex.Regex;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.discovery.MasterNotDiscoveredException;
 import org.elasticsearch.persistent.PersistentTasksCustomMetaData;
+import org.elasticsearch.persistent.PersistentTasksCustomMetaData.PersistentTask;
 import org.elasticsearch.persistent.PersistentTasksService;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.tasks.Task;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportService;
 import org.elasticsearch.xpack.core.action.util.PageParams;
+import org.elasticsearch.xpack.core.transform.TransformField;
 import org.elasticsearch.xpack.core.transform.TransformMessages;
 import org.elasticsearch.xpack.core.transform.action.StopTransformAction;
 import org.elasticsearch.xpack.core.transform.action.StopTransformAction.Request;
 import org.elasticsearch.xpack.core.transform.action.StopTransformAction.Response;
 import org.elasticsearch.xpack.core.transform.transforms.TransformState;
+import org.elasticsearch.xpack.core.transform.transforms.TransformTaskParams;
 import org.elasticsearch.xpack.core.transform.transforms.TransformTaskState;
 import org.elasticsearch.xpack.core.transform.transforms.persistence.TransformInternalIndexConstants;
 import org.elasticsearch.xpack.transform.TransformServices;
@@ -47,6 +54,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -127,6 +135,25 @@ public class TransportStopTransformAction extends TransportTasksAction<Transform
         }
     }
 
+    static Tuple<Set<String>, Set<String>> findTasksWithoutConfig(ClusterState state, String transformId) {
+        PersistentTasksCustomMetaData tasks = state.metaData().custom(PersistentTasksCustomMetaData.TYPE);
+
+        Set<String> taskIds = new HashSet<>();
+        Set<String> executorNodes = new HashSet<>();
+
+        Predicate<PersistentTask<?>> taskMatcher = Strings.isAllOrWildcard(new String[] { transformId }) ? t -> true : t -> {
+            TransformTaskParams transformParams = (TransformTaskParams) t.getParams();
+            return Regex.simpleMatch(transformId, transformParams.getId());
+        };
+
+        for (PersistentTasksCustomMetaData.PersistentTask<?> pTask : tasks.findTasks(TransformField.TASK_NAME, taskMatcher)) {
+            executorNodes.add(pTask.getExecutorNode());
+            taskIds.add(pTask.getId());
+        }
+
+        return new Tuple<>(taskIds, executorNodes);
+    }
+
     @Override
     protected void doExecute(Task task, Request request, ActionListener<Response> listener) {
         final ClusterState state = clusterService.state();
@@ -160,7 +187,31 @@ public class TransportStopTransformAction extends TransportTasksAction<Transform
                     request.setExpandedIds(new HashSet<>(hitsAndIds.v2()));
                     request.setNodes(TransformNodes.transformTaskNodes(hitsAndIds.v2(), state));
                     super.doExecute(task, request, finalListener);
-                }, listener::onFailure)
+                }, e -> {
+                    if (e instanceof ResourceNotFoundException) {
+                        Tuple<Set<String>, Set<String>> runningTasksAndNodes = findTasksWithoutConfig(state, request.getId());
+                        if (runningTasksAndNodes.v1().isEmpty()) {
+                            listener.onFailure(e);
+                            // found transforms without a config
+                        } else if (request.isForce()) {
+                            request.setExpandedIds(runningTasksAndNodes.v1());
+                            request.setNodes(runningTasksAndNodes.v2().toArray(new String[0]));
+                            super.doExecute(task, request, finalListener);
+                        } else {
+                            listener.onFailure(
+                                new ElasticsearchStatusException(
+                                    TransformMessages.getMessage(
+                                        TransformMessages.REST_STOP_TRANSFORM_WITHOUT_CONFIG,
+                                        Strings.arrayToCommaDelimitedString(runningTasksAndNodes.v1().toArray(new String[0]))
+                                    ),
+                                    RestStatus.CONFLICT
+                                )
+                            );
+                        }
+                    } else {
+                        listener.onFailure(e);
+                    }
+                })
             );
         }
     }