Clean up files

Signed-off-by: Andy Qin <qinandy@amazon.com>

Author: q-andy

DEVELOPER_GUIDE.md

@@ -351,9 +351,9 @@ through the same build issue.
 
 ### Class and package names
 
-Class names should use `CamelCase`.
+Class names should use `CamelCase`. 
 
-Try to put new classes into existing packages if package name abstracts the purpose of the class.
+Try to put new classes into existing packages if package name abstracts the purpose of the class. 
 
 Example of good class file name and package utilization:
 
@@ -371,7 +371,7 @@ methods rather than a long single one and does everything.
 ### Documentation
 
 Document you code. That includes purpose of new classes, every public method and code sections that have critical or non-trivial
-logic (check this example https://github.com/opensearch-project/neural-search/blob/main/src/main/java/org/opensearch/neuralsearch/query/NeuralQueryBuilder.java#L238).
+logic (check this example https://github.com/opensearch-project/neural-search/blob/main/src/main/java/org/opensearch/neuralsearch/query/NeuralQueryBuilder.java#L238). 
 
 When you submit a feature PR, please submit a new
 [documentation issue](https://github.com/opensearch-project/documentation-website/issues/new/choose). This is a path for the documentation to be published as part of https://opensearch.org/docs/latest/ documentation site.
@@ -384,17 +384,17 @@ For the most part, we're using common conventions for Java projects. Here are a
 
 1. Use descriptive names for classes, methods, fields, and variables.
 2. Avoid abbreviations unless they are widely accepted
-3. Use `final` on all method arguments unless it's absolutely necessary
+3. Use `final` on all method arguments unless it's absolutely necessary 
 4. Wildcard imports are not allowed.
 5. Static imports are preferred over qualified imports when using static methods
 6. Prefer creating non-static public methods whenever possible. Avoid static methods in general, as they can often serve as shortcuts.
 Static methods are acceptable if they are private and do not access class state.
-7. Use functional programming style inside methods unless it's a performance critical section.
+7. Use functional programming style inside methods unless it's a performance critical section. 
 8. For parameters of lambda expression please use meaningful names instead of shorten cryptic ones.
 9. Use Optional for return values if the value may not be present. This should be preferred to returning null.
 10. Do not create checked exceptions, and do not throw checked exceptions from public methods whenever possible. In general, if you call a method with a checked exception, you should wrap that exception into an unchecked exception.
 11. Throwing checked exceptions from private methods is acceptable.
-12. Use String.format when a string includes parameters, and prefer this over direct string concatenation. Always specify a Locale with String.format;
+12. Use String.format when a string includes parameters, and prefer this over direct string concatenation. Always specify a Locale with String.format; 
 as a rule of thumb, use Locale.ROOT.
 13. Prefer Lombok annotations to the manually written boilerplate code
 14. When throwing an exception, avoid including user-provided content in the exception message. For secure coding practices,
@@ -440,17 +440,17 @@ Fix any new warnings before submitting your PR to ensure proper code documentati
 
 ### Tests
 
-Write unit and integration tests for your new functionality.
+Write unit and integration tests for your new functionality. 
 
 Unit tests are preferred as they are cheap and fast, try to use them to cover all possible
-combinations of parameters. Utilize mocks to mimic dependencies.
+combinations of parameters. Utilize mocks to mimic dependencies. 
 
-Integration tests should be used sparingly, focusing primarily on the main (happy path) scenario or cases where extensive
-mocking is impractical. Include one or two unhappy paths to confirm that correct response codes are returned to the user.
-Whenever possible, favor scenarios that do not require model deployment. If model deployment is necessary, use an existing
+Integration tests should be used sparingly, focusing primarily on the main (happy path) scenario or cases where extensive 
+mocking is impractical. Include one or two unhappy paths to confirm that correct response codes are returned to the user. 
+Whenever possible, favor scenarios that do not require model deployment. If model deployment is necessary, use an existing 
 model, as tests involving new model deployments are the most resource-intensive.
 
-If your changes could affect backward compatibility, please include relevant backward compatibility tests along with your
+If your changes could affect backward compatibility, please include relevant backward compatibility tests along with your 
 PR. For guidance on adding these tests, refer to the [Backwards Compatibility Testing](#backwards-compatibility-testing) section in this guide.
 
 ### Outdated or irrelevant code

src/main/java/org/opensearch/neuralsearch/rest/RestNeuralStatsHandler.java

@@ -41,13 +41,13 @@ public class RestNeuralStatsHandler extends BaseRestHandler {
 
     private static final Set<String> EVENT_STAT_NAMES = EnumSet.allOf(EventStatName.class)
         .stream()
-        .map(EventStatName::getName)
+        .map(EventStatName::getNameString)
         .map(String::toLowerCase)
         .collect(Collectors.toSet());
 
     private static final Set<String> STATE_STAT_NAMES = EnumSet.allOf(StateStatName.class)
         .stream()
-        .map(StateStatName::getName)
+        .map(StateStatName::getNameString)
         .map(String::toLowerCase)
         .collect(Collectors.toSet());
 

src/main/java/org/opensearch/neuralsearch/stats/common/StatName.java

@@ -13,7 +13,7 @@ public interface StatName {
      * Gets the name of the stat. These must be unique to support user request stat filtering.
      * @return the name of the stat
      */
-    String getName();
+    String getNameString();
 
     /**
      * Gets the path of the stat in dot notation.

src/main/java/org/opensearch/neuralsearch/stats/common/StatType.java

@@ -13,5 +13,5 @@ public interface StatType {
      * Get the name of the stat type containing info about the type and how to process it
      * @return name of the stat type
      */
-    String getName();
+    String getTypeString();
 }

src/main/java/org/opensearch/neuralsearch/stats/events/EventStat.java

@@ -4,6 +4,8 @@
  */
 package org.opensearch.neuralsearch.stats.events;
 
+import org.opensearch.neuralsearch.stats.common.StatSnapshot;
+
 /**
  * Interface for event stats. These contain logic to store and update ongoing event information.
  */
@@ -18,7 +20,7 @@ public interface EventStat {
      * Returns a snapshot of the stat. Used to cross transport layer/rest layer
      * @return
      */
-    TimestampedEventStatSnapshot getEventStatSnapshot();
+    StatSnapshot<?> getStatSnapshot();
 
     /**
      * Increments the stat

src/main/java/org/opensearch/neuralsearch/stats/events/EventStatName.java

@@ -19,21 +19,24 @@
 public enum EventStatName implements StatName {
     TEXT_EMBEDDING_PROCESSOR_EXECUTIONS("text_embedding_executions", "processors.ingest", EventStatType.TIMESTAMPED_COUNTER);
 
-    private final String name;
+    private final String nameString;
     private final String path;
     private final EventStatType statType;
 
+    /**
+     * Enum lookup table by nameString
+     */
     private static final Map<String, EventStatName> BY_NAME = Arrays.stream(values())
-        .collect(Collectors.toMap(stat -> stat.name, stat -> stat));
+        .collect(Collectors.toMap(stat -> stat.nameString, stat -> stat));
 
     /**
      * Constructor
-     * @param name the unique name of the stat.
+     * @param nameString the unique name of the stat.
      * @param path the unique path of the stat
      * @param statType the category of stat
      */
-    EventStatName(String name, String path, EventStatType statType) {
-        this.name = name;
+    EventStatName(String nameString, String path, EventStatType statType) {
+        this.nameString = nameString;
         this.path = path;
         this.statType = statType;
     }
@@ -57,13 +60,13 @@ public static EventStatName from(String name) {
      */
     public String getFullPath() {
         if (StringUtils.isBlank(path)) {
-            return name;
+            return nameString;
         }
-        return String.join(".", path, name);
+        return String.join(".", path, nameString);
     }
 
     @Override
     public String toString() {
-        return getName();
+        return getNameString();
     }
 }

src/main/java/org/opensearch/neuralsearch/stats/events/EventStatType.java

@@ -18,7 +18,7 @@ public enum EventStatType implements StatType {
      * Gets the name of the stat type, the enum name in lowercase
      * @return the name of the stat type
      */
-    public String getName() {
+    public String getTypeString() {
         return name().toLowerCase(Locale.ROOT);
     }
 }

src/main/java/org/opensearch/neuralsearch/stats/events/EventStatsManager.java

@@ -6,6 +6,7 @@
 
 import lombok.Getter;
 import org.opensearch.neuralsearch.settings.NeuralSearchSettingsAccessor;
+import org.opensearch.neuralsearch.stats.common.StatSnapshot;
 
 import java.util.EnumSet;
 import java.util.HashMap;
@@ -79,13 +80,16 @@ public void inc(EventStatName eventStatName) {
      * @param statsToRetrieve Set of event stat names to retrieve data for
      * @return Map of event stat names to their current snapshots
      */
-    public Map<EventStatName, TimestampedEventStatSnapshot> getEventStatSnapshots(EnumSet<EventStatName> statsToRetrieve) {
+    public Map<EventStatName, TimestampedEventStatSnapshot> getTimestampedEventStatSnapshots(EnumSet<EventStatName> statsToRetrieve) {
         // Filter stats based on passed in collection
         Map<EventStatName, TimestampedEventStatSnapshot> eventStatsDataMap = new HashMap<>();
         for (EventStatName statName : statsToRetrieve) {
-            if (stats.containsKey(statName)) {
-                // Get event data snapshot
-                eventStatsDataMap.put(statName, stats.get(statName).getEventStatSnapshot());
+            if (stats.containsKey(statName) && statName.getStatType() == EventStatType.TIMESTAMPED_COUNTER) {
+                StatSnapshot<?> snapshot = stats.get(statName).getStatSnapshot();
+                if (snapshot instanceof TimestampedEventStatSnapshot) {
+                    // Get event data snapshot
+                    eventStatsDataMap.put(statName, (TimestampedEventStatSnapshot) snapshot);
+                }
             }
         }
         return eventStatsDataMap;

src/main/java/org/opensearch/neuralsearch/stats/events/TimestampedEventStat.java

@@ -119,7 +119,7 @@ public long getMinutesSinceLastEvent() {
      * Gets the StatSnapshot for the event stat data
      * @return
      */
-    public TimestampedEventStatSnapshot getEventStatSnapshot() {
+    public TimestampedEventStatSnapshot getStatSnapshot() {
         return TimestampedEventStatSnapshot.builder()
             .statName(statName)
             .value(getValue())

src/main/java/org/opensearch/neuralsearch/stats/events/TimestampedEventStatSnapshot.java

@@ -126,7 +126,7 @@ public static TimestampedEventStatSnapshot aggregateEventStatSnapshots(Collectio
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();
         builder.field(StatSnapshot.VALUE_FIELD, value);
-        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getName());
+        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getTypeString());
         builder.field(TRAILING_INTERVAL_KEY, trailingIntervalValue);
         builder.field(MINUTES_SINCE_LAST_EVENT_KEY, minutesSinceLastEvent);
         builder.endObject();

src/main/java/org/opensearch/neuralsearch/stats/state/CountableStateStatSnapshot.java

@@ -56,7 +56,7 @@ public void incrementBy(Long delta) {
     public XContentBuilder toXContent(XContentBuilder builder, ToXContent.Params params) throws IOException {
         builder.startObject();
         builder.field(StatSnapshot.VALUE_FIELD, getValue());
-        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getName());
+        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getTypeString());
         builder.endObject();
         return builder;
     }

src/main/java/org/opensearch/neuralsearch/stats/state/SettableStateStatSnapshot.java

@@ -54,7 +54,7 @@ public SettableStateStatSnapshot(StateStatName statName, T value) {
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();
         builder.field(StatSnapshot.VALUE_FIELD, getValue());
-        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getName());
+        builder.field(StatSnapshot.STAT_TYPE_FIELD, statName.getStatType().getTypeString());
         builder.endObject();
         return builder;
     }

src/main/java/org/opensearch/neuralsearch/stats/state/StateStatName.java

@@ -21,29 +21,29 @@ public enum StateStatName implements StatName {
     CLUSTER_VERSION("cluster_version", "", StateStatType.SETTABLE),
     TEXT_EMBEDDING_PROCESSORS("text_embedding_processors_in_pipelines", "processors.ingest", StateStatType.COUNTABLE);
 
-    private final String name;
+    private final String nameString;
     private final String path;
     private final StateStatType statType;
 
     private static final Map<String, StateStatName> BY_NAME = Arrays.stream(values())
-        .collect(Collectors.toMap(stat -> stat.name, stat -> stat));
+        .collect(Collectors.toMap(stat -> stat.nameString, stat -> stat));
 
     /**
      * Constructor
-     * @param name the unique name of the stat.
+     * @param nameString the unique name of the stat.
      * @param path the unique path of the stat
      * @param statType the category of stat
      */
-    StateStatName(String name, String path, StateStatType statType) {
-        this.name = name;
+    StateStatName(String nameString, String path, StateStatType statType) {
+        this.nameString = nameString;
         this.path = path;
         this.statType = statType;
     }
 
     /**
      * Gets the StatName associated with a unique string name
      * @throws IllegalArgumentException if stat name does not exist
-     * @param name the string name of the stat
+     * @param value the string name of the stat
      * @return the StatName enum associated with that String name
      */
     public static StateStatName from(String value) {
@@ -59,13 +59,13 @@ public static StateStatName from(String value) {
      */
     public String getFullPath() {
         if (StringUtils.isBlank(path)) {
-            return name;
+            return nameString;
         }
-        return String.join(".", path, name);
+        return String.join(".", path, nameString);
     }
 
     @Override
     public String toString() {
-        return getName();
+        return getNameString();
     }
 }

src/main/java/org/opensearch/neuralsearch/stats/state/StateStatType.java

@@ -19,7 +19,7 @@ public enum StateStatType implements StatType {
      * Gets the name of the stat type, the enum name in lowercase
      * @return the name of the stat type
      */
-    public String getName() {
+    public String getTypeString() {
         return name().toLowerCase(Locale.ROOT);
     }
 }

src/main/java/org/opensearch/neuralsearch/transport/NeuralStatsTransportAction.java

@@ -126,11 +126,18 @@ protected NeuralStatsNodeResponse newNodeResponse(StreamInput in) throws IOExcep
         return new NeuralStatsNodeResponse(in);
     }
 
+    /**
+     * Node operation to retrieve stats from node local event stats manager
+     * @param request the node level request
+     * @return the node level response containing node level event stats
+     */
     @Override
     protected NeuralStatsNodeResponse nodeOperation(NeuralStatsNodeRequest request) {
         // Reads from NeuralStats to node level stats on an individual node
         EnumSet<EventStatName> eventStatsToRetrieve = request.getRequest().getNeuralStatsInput().getEventStatNames();
-        Map<EventStatName, TimestampedEventStatSnapshot> eventStatDataMap = eventStatsManager.getEventStatSnapshots(eventStatsToRetrieve);
+        Map<EventStatName, TimestampedEventStatSnapshot> eventStatDataMap = eventStatsManager.getTimestampedEventStatSnapshots(
+            eventStatsToRetrieve
+        );
 
         return new NeuralStatsNodeResponse(clusterService.localNode(), eventStatDataMap);
     }

src/main/java/org/opensearch/neuralsearch/util/PipelineServiceUtil.java

@@ -26,8 +26,8 @@ public class PipelineServiceUtil {
     private static PipelineServiceUtil INSTANCE;
 
     /**
-     * Return instance of the cluster context, must be initialized first for proper usage
-     * @return instance of cluster context
+     * Return instance of the pipeline context, must be initialized first for proper usage
+     * @return instance of pipeline context
      */
     public static synchronized PipelineServiceUtil instance() {
         if (INSTANCE == null) {

src/test/java/org/opensearch/neuralsearch/rest/RestNeuralStatsHandlerIT.java

@@ -100,7 +100,10 @@ public void test_textEmbedding() throws Exception {
     }
 
     public void test_statsFiltering() throws Exception {
-        Response response = executeNeuralStatRequest(new ArrayList<>(), Arrays.asList(StateStatName.TEXT_EMBEDDING_PROCESSORS.getName()));
+        Response response = executeNeuralStatRequest(
+            new ArrayList<>(),
+            Arrays.asList(StateStatName.TEXT_EMBEDDING_PROCESSORS.getNameString())
+        );
 
         String responseBody = EntityUtils.toString(response.getEntity());
         Map<String, Object> stats = parseStatsResponse(responseBody);
@@ -143,7 +146,7 @@ public void test_includeMetadata() throws Exception {
         String valueWithMetadata = ((Map<String, String>) clusterVersionStatMetadata).get(StatSnapshot.VALUE_FIELD);
 
         // Stat type metadata should match
-        assertEquals(StateStatType.SETTABLE.getName(), statType);
+        assertEquals(StateStatType.SETTABLE.getTypeString(), statType);
 
         // Fetch Without metadata
         params.put(RestNeuralStatsHandler.INCLUDE_METADATA_PARAM, "false");

src/test/java/org/opensearch/neuralsearch/stats/NeuralStatsInputTests.java

@@ -133,8 +133,8 @@ public void test_toXContent() throws IOException {
         Map<String, Object> responseMap = xContentBuilderToMap(builder);
 
         assertEquals(Collections.singletonList(NODE_ID_1), responseMap.get("node_ids"));
-        assertEquals(Collections.singletonList(EVENT_STAT.getName()), responseMap.get("event_stats"));
-        assertEquals(Collections.singletonList(STATE_STAT.getName()), responseMap.get("state_stats"));
+        assertEquals(Collections.singletonList(EVENT_STAT.getNameString()), responseMap.get("event_stats"));
+        assertEquals(Collections.singletonList(STATE_STAT.getNameString()), responseMap.get("state_stats"));
         assertEquals(true, responseMap.get("include_metadata"));
         assertEquals(true, responseMap.get("flat_keys"));
     }

src/test/java/org/opensearch/neuralsearch/stats/events/EventStatNameTests.java

@@ -17,7 +17,7 @@ public class EventStatNameTests extends OpenSearchTestCase {
     public static final EnumSet<EventStatName> EVENT_STATS = EnumSet.allOf(EventStatName.class);
 
     public void test_from_valid() {
-        String validStatName = EventStatName.TEXT_EMBEDDING_PROCESSOR_EXECUTIONS.getName();
+        String validStatName = EventStatName.TEXT_EMBEDDING_PROCESSOR_EXECUTIONS.getNameString();
         EventStatName result = EventStatName.from(validStatName);
         assertEquals(EventStatName.TEXT_EMBEDDING_PROCESSOR_EXECUTIONS, result);
     }
@@ -29,7 +29,7 @@ public void test_from_invalid() {
     public void test_unique_names() {
         Set<String> names = new HashSet<>();
         for (EventStatName statName : EVENT_STATS) {
-            String name = statName.getName().toLowerCase(Locale.ROOT);
+            String name = statName.getNameString().toLowerCase(Locale.ROOT);
             assertFalse(String.format("Checking name uniqueness for %s", name), names.contains(name));
             names.add(name);
         }