Fix "Clean up operation statistics" button

Now it erases also statistics in the activity state tree.
(In a single task, currently.)

To review: changed PageTask.createDeleteItemDelta method.

gui/admin-gui/src/main/java/com/evolveum/midpoint/web/page/admin/server/PageTask.java

@@ -10,11 +10,15 @@
 
 import java.io.InputStream;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 
 import com.evolveum.midpoint.gui.api.prism.ItemStatus;
 
+import com.evolveum.midpoint.schema.statistics.ActivityStatisticsUtil;
+import com.evolveum.midpoint.schema.util.task.ActivityStateUtil;
+
 import org.apache.commons.collections4.CollectionUtils;
 import org.apache.wicket.Page;
 import org.apache.wicket.ajax.AjaxRequestTarget;
@@ -381,7 +385,7 @@ public StringResourceModel getTitle() {
                     @Override
                     public void yesPerformed(AjaxRequestTarget target) {
                         try {
-                            deleteItem(target, TaskType.F_OPERATION_STATS);
+                            deleteStatistics(target);
                         } catch (Exception e) {
                             LOGGER.error("Cannot delete task operation statistics, {}", e.getMessage(), e);
                             getSession().error(PageTask.this.getString("PageTask.cleanup.operationStatistics.failed"));
@@ -396,12 +400,19 @@ public void yesPerformed(AjaxRequestTarget target) {
         repeatingView.add(cleanupPerformance);
     }
 
-    private void deleteItem(AjaxRequestTarget target, ItemName... itemName) throws SchemaException {
+    private void deleteStatistics(AjaxRequestTarget target) throws SchemaException {
+        List<ItemPath> statisticsPaths = new ArrayList<>();
+        statisticsPaths.add(TaskType.F_OPERATION_STATS);
+        statisticsPaths.addAll(ActivityStatisticsUtil.getAllStatisticsPaths(getTask()));
+        deleteItem(target, statisticsPaths.toArray(new ItemPath[0]));
+    }
+
+    private void deleteItem(AjaxRequestTarget target, ItemPath... paths) throws SchemaException {
         Collection<ItemDelta<?, ?>> itemDeltas = new ArrayList<>();
-        for (ItemName item : itemName) {
-            ItemDelta<?, ?> delta = createDeleteItemDelta(item);
+        for (ItemPath path : paths) {
+            ItemDelta<?, ?> delta = createDeleteItemDelta(path);
             if (delta == null) {
-                LOGGER.trace("Nothing to delete for {}", item);
+                LOGGER.trace("Nothing to delete for {}", path);
                 continue;
             }
             itemDeltas.add(delta);
@@ -446,27 +457,12 @@ public void yesPerformed(AjaxRequestTarget target) {
         repeatingView.add(cleanupResults);
     }
 
-    private ItemDelta<?, ?> createDeleteItemDelta(ItemName itemName) throws SchemaException {
-        ItemWrapper<?, ?> item = getObjectWrapper().findItem(itemName, ItemWrapper.class);
-        if (item == null) {
-            return null;
-        }
-
-        PrismValueWrapper<?> itemValue = item.getValue();
-        if (itemValue == null) {
-            return null;
-        }
-
-        PrismValue newValue = itemValue.getNewValue();
-        if (newValue == null || newValue.isEmpty()) {
-            return null;
-        }
-
+    private ItemDelta<?, ?> createDeleteItemDelta(ItemPath itemPath) throws SchemaException {
+        // Originally here was a code that looked at item wrapper - why?
+        // Removed because it didn't allow to remove values not covered by wrapper, like activityState/activity/statistics.
         return getPrismContext().deltaFor(TaskType.class)
-                .item(itemName)
-                .replace()
+                .item(itemPath).replace()
                 .asItemDelta();
-
     }
 
     private void saveTaskChanges(AjaxRequestTarget target, ObjectDelta<TaskType> taskDelta) {

infra/schema/src/main/java/com/evolveum/midpoint/schema/statistics/ActivityStatisticsUtil.java

@@ -7,6 +7,7 @@
 
 package com.evolveum.midpoint.schema.statistics;
 
+import com.evolveum.midpoint.prism.path.ItemPath;
 import com.evolveum.midpoint.schema.util.task.ActivityItemProcessingStatisticsUtil;
 import com.evolveum.midpoint.schema.util.task.ActivityPath;
 
@@ -16,6 +17,7 @@
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
@@ -134,4 +136,32 @@ private static Stream<ObjectActionsExecutedEntryType> getAllActionsExecuted(
                 state.getStatistics().getActionsExecuted() != null ?
                 state.getStatistics().getActionsExecuted().getObjectActionsEntry().stream() : Stream.empty();
     }
+
+    /**
+     * Returns all paths in activity states that point to the statistics.
+     * Local to the current task!
+     */
+    public static List<ItemPath> getAllStatisticsPaths(@NotNull TaskType task) {
+        return getStatePathsStream(task)
+                .map(path -> path.append(ActivityStateType.F_STATISTICS))
+                .collect(Collectors.toList());
+    }
+
+    public static Stream<ItemPath> getStatePathsStream(@NotNull TaskType task) {
+        ItemPath rootPath = ItemPath.create(TaskType.F_ACTIVITY_STATE, TaskActivityStateType.F_ACTIVITY);
+        ActivityStateType rootActivity = task.getActivityState() != null ? task.getActivityState().getActivity() : null;
+
+        if (rootActivity == null) {
+            return Stream.empty();
+        } else {
+            return Stream.concat(
+                    Stream.of(rootPath),
+                    getStatePathsStream(rootActivity.getActivity(), rootPath.append(ActivityStateType.F_ACTIVITY)));
+        }
+    }
+
+    private static Stream<ItemPath> getStatePathsStream(@NotNull List<ActivityStateType> states, @NotNull ItemPath path) {
+        return states.stream()
+                .map(state -> path.append(state.getId()));
+    }
 }