AMBARI-14812 - Alerts API Does Not Honor JPA Sorting (jonathanhurley)

ambari-server/src/main/java/org/apache/ambari/server/controller/internal/AlertDefinitionResourceProvider.java

@@ -23,6 +23,7 @@ import java.util.Collection;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -223,7 +224,8 @@ public class AlertDefinitionResourceProvider extends AbstractControllerResourceP
 
     Set<String> requestPropertyIds = getRequestPropertyIds(request, predicate);
 
-    Set<Resource> results = new HashSet<Resource>();
+    // use a collection which preserves order since JPA sorts the results
+    Set<Resource> results = new LinkedHashSet<Resource>();
 
     for (Map<String, Object> propertyMap : getPropertyMaps(predicate)) {
       String clusterName = (String) propertyMap.get(ALERT_DEF_CLUSTER_NAME);

ambari-server/src/main/java/org/apache/ambari/server/controller/internal/AlertResourceProvider.java

@@ -21,6 +21,7 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -43,9 +44,9 @@ import org.apache.ambari.server.orm.dao.AlertsDAO;
 import org.apache.ambari.server.orm.entities.AlertCurrentEntity;
 import org.apache.ambari.server.orm.entities.AlertDefinitionEntity;
 import org.apache.ambari.server.orm.entities.AlertHistoryEntity;
+import org.apache.commons.lang.StringUtils;
 
 import com.google.inject.Inject;
-import org.apache.commons.lang.StringUtils;
 
 /**
  * ResourceProvider for Alert instances
@@ -150,7 +151,8 @@ public class AlertResourceProvider extends ReadOnlyResourceProvider implements
 
     Set<String> requestPropertyIds = getRequestPropertyIds(request, predicate);
 
-    Set<Resource> results = new HashSet<Resource>();
+    // use a collection which preserves order since JPA sorts the results
+    Set<Resource> results = new LinkedHashSet<Resource>();
 
     for (Map<String, Object> propertyMap : getPropertyMaps(predicate)) {
 

ambari-server/src/test/java/org/apache/ambari/server/orm/dao/AlertsDAOTest.java

@@ -411,6 +411,44 @@ public class AlertsDAOTest {
     assertEquals(0, currentAlerts.size());
   }
 
+  /**
+   * Tests that the Ambari sort is correctly applied to JPA quuery.
+   *
+   * @throws Exception
+   */
+  @Test
+  public void testAlertCurrentSorting() throws Exception {
+    AlertCurrentRequest request = new AlertCurrentRequest();
+
+    Predicate clusterPredicate = new PredicateBuilder().property(
+        AlertResourceProvider.ALERT_CLUSTER_NAME).equals(m_cluster.getClusterName()).toPredicate();
+
+    request.Predicate = clusterPredicate;
+
+    SortRequestProperty sortRequestProperty = new SortRequestProperty(AlertResourceProvider.ALERT_ID, Order.ASC);
+    request.Sort = new SortRequestImpl(Collections.singletonList(sortRequestProperty));
+
+    List<AlertCurrentEntity> currentAlerts = m_dao.findAll(request);
+    assertTrue(currentAlerts.size() >= 5);
+    long lastId = Long.MIN_VALUE;
+    for (AlertCurrentEntity alert : currentAlerts) {
+      assertTrue(lastId < alert.getAlertId());
+      lastId = alert.getAlertId();
+    }
+
+    // change the sort to DESC
+    sortRequestProperty = new SortRequestProperty(AlertResourceProvider.ALERT_ID, Order.DESC);
+    request.Sort = new SortRequestImpl(Collections.singletonList(sortRequestProperty));
+
+    currentAlerts = m_dao.findAll(request);
+    assertTrue(currentAlerts.size() >= 5);
+    lastId = Long.MAX_VALUE;
+    for (AlertCurrentEntity alert : currentAlerts) {
+      assertTrue(lastId > alert.getAlertId());
+      lastId = alert.getAlertId();
+    }
+  }
+
   /**
    * Tests that the {@link AlertCurrentEntity} fields are updated properly when
    * a new {@link AlertHistoryEntity} is associated.