star tree file formats meta and data writer

Signed-off-by: Sarthak Aggarwal <[email protected]>

server/src/main/java/org/opensearch/index/compositeindex/CompositeIndexConstants.java

@@ -0,0 +1,26 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.compositeindex;
+
+/**
+ * This class contains constants used in the Composite Index implementation.
+ */
+public class CompositeIndexConstants {
+
+    /**
+     * The magic marker value used for sanity checks in the Composite Index implementation.
+     */
+    public static final long COMPOSITE_FIELD_MARKER = 0xC0950513F1E1DL; // Composite Field
+
+    /**
+     * Represents the key to fetch number of documents in a segment.
+     */
+    public static final String SEGMENT_DOCS_COUNT = "segmentDocsCount";
+
+}

server/src/main/java/org/opensearch/index/compositeindex/CompositeIndexMetadata.java

@@ -0,0 +1,53 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.compositeindex;
+
+import org.opensearch.index.mapper.CompositeMappedFieldType;
+
+/**
+ * This class represents the metadata of a Composite Index, which includes information about
+ * the composite field name, type, and the specific metadata for the type of composite field
+ * (e.g., Tree metadata).
+ *
+ * @opensearch.experimental
+ */
+public class CompositeIndexMetadata {
+
+    private final String compositeFieldName;
+    private final CompositeMappedFieldType.CompositeFieldType compositeFieldType;
+
+    /**
+     * Constructs a CompositeIndexMetadata object with the provided composite field name and type.
+     *
+     * @param compositeFieldName the name of the composite field
+     * @param compositeFieldType the type of the composite field
+     */
+    public CompositeIndexMetadata(String compositeFieldName, CompositeMappedFieldType.CompositeFieldType compositeFieldType) {
+        this.compositeFieldName = compositeFieldName;
+        this.compositeFieldType = compositeFieldType;
+    }
+
+    /**
+     * Returns the name of the composite field.
+     *
+     * @return the composite field name
+     */
+    public String getCompositeFieldName() {
+        return compositeFieldName;
+    }
+
+    /**
+     * Returns the type of the composite field.
+     *
+     * @return the composite field type
+     */
+    public CompositeMappedFieldType.CompositeFieldType getCompositeFieldType() {
+        return compositeFieldType;
+    }
+}

server/src/main/java/org/opensearch/index/compositeindex/datacube/MetricStat.java

@@ -17,22 +17,28 @@
  */
 @ExperimentalApi
 public enum MetricStat {
-    COUNT("count"),
-    AVG("avg"),
-    SUM("sum"),
-    MIN("min"),
-    MAX("max");
+    COUNT("count", 0),
+    AVG("avg", 1),
+    SUM("sum", 2),
+    MIN("min", 3),
+    MAX("max", 4);
 
     private final String typeName;
+    private final int metricOrdinal;
 
-    MetricStat(String typeName) {
+    MetricStat(String typeName, int metricOrdinal) {
         this.typeName = typeName;
+        this.metricOrdinal = metricOrdinal;
     }
 
     public String getTypeName() {
         return typeName;
     }
 
+    public int getMetricOrdinal() {
+        return metricOrdinal;
+    }
+
     public static MetricStat fromTypeName(String typeName) {
         for (MetricStat metric : MetricStat.values()) {
             if (metric.getTypeName().equalsIgnoreCase(typeName)) {
@@ -41,4 +47,13 @@ public static MetricStat fromTypeName(String typeName) {
         }
         throw new IllegalArgumentException("Invalid metric stat: " + typeName);
     }
+
+    public static MetricStat fromMetricOrdinal(int metricOrdinal) {
+        for (MetricStat metric : MetricStat.values()) {
+            if (metric.getMetricOrdinal() == metricOrdinal) {
+                return metric;
+            }
+        }
+        throw new IllegalArgumentException("Invalid metric stat: " + metricOrdinal);
+    }
 }

server/src/main/java/org/opensearch/index/compositeindex/datacube/ReadDimension.java

@@ -0,0 +1,55 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.compositeindex.datacube;
+
+import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.index.mapper.CompositeDataCubeFieldType;
+
+import java.io.IOException;
+import java.util.Objects;
+
+/**
+ * Composite index merge dimension class
+ *
+ * @opensearch.experimental
+ */
+public class ReadDimension implements Dimension {
+    public static final String READ = "read";
+    private final String field;
+
+    public ReadDimension(String field) {
+        this.field = field;
+    }
+
+    public String getField() {
+        return field;
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        builder.field(CompositeDataCubeFieldType.NAME, field);
+        builder.field(CompositeDataCubeFieldType.TYPE, READ);
+        builder.endObject();
+        return builder;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        ReadDimension dimension = (ReadDimension) o;
+        return Objects.equals(field, dimension.getField());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(field);
+    }
+}

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/StarTreeFieldConfiguration.java

@@ -56,19 +56,25 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
     @ExperimentalApi
     public enum StarTreeBuildMode {
         // TODO : remove onheap support unless this proves useful
-        ON_HEAP("onheap"),
-        OFF_HEAP("offheap");
+        ON_HEAP("onheap", (byte) 0),
+        OFF_HEAP("offheap", (byte) 1);
 
         private final String typeName;
+        private final byte buildModeOrdinal;
 
-        StarTreeBuildMode(String typeName) {
+        StarTreeBuildMode(String typeName, byte buildModeOrdinal) {
             this.typeName = typeName;
+            this.buildModeOrdinal = buildModeOrdinal;
         }
 
         public String getTypeName() {
             return typeName;
         }
 
+        public byte getBuildModeOrdinal() {
+            return buildModeOrdinal;
+        }
+
         public static StarTreeBuildMode fromTypeName(String typeName) {
             for (StarTreeBuildMode starTreeBuildMode : StarTreeBuildMode.values()) {
                 if (starTreeBuildMode.getTypeName().equalsIgnoreCase(typeName)) {
@@ -77,6 +83,16 @@ public static StarTreeBuildMode fromTypeName(String typeName) {
             }
             throw new IllegalArgumentException(String.format(Locale.ROOT, "Invalid star tree build mode: [%s] ", typeName));
         }
+
+        public static StarTreeBuildMode fromBuildModeOrdinal(byte buildModeOrdinal) {
+            for (StarTreeBuildMode starTreeBuildMode : StarTreeBuildMode.values()) {
+                if (starTreeBuildMode.getBuildModeOrdinal() == buildModeOrdinal) {
+                    return starTreeBuildMode;
+                }
+            }
+            throw new IllegalArgumentException(String.format(Locale.ROOT, "Invalid star tree build mode: [%s] ", buildModeOrdinal));
+        }
+
     }
 
     public int maxLeafDocs() {

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/fileformats/StarTreeWriter.java

@@ -0,0 +1,78 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+package org.opensearch.index.compositeindex.datacube.startree.fileformats;
+
+import org.apache.lucene.store.IndexOutput;
+import org.opensearch.index.compositeindex.datacube.startree.StarTreeField;
+import org.opensearch.index.compositeindex.datacube.startree.aggregators.MetricAggregatorInfo;
+import org.opensearch.index.compositeindex.datacube.startree.fileformats.data.StarTreeDataWriter;
+import org.opensearch.index.compositeindex.datacube.startree.fileformats.meta.StarTreeMetaWriter;
+import org.opensearch.index.compositeindex.datacube.startree.node.InMemoryTreeNode;
+
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Util class for building star tree
+ *
+ * @opensearch.experimental
+ */
+public class StarTreeWriter {
+
+    /** Initial version for the star tree writer */
+    public static final int VERSION_START = 0;
+
+    /** Current version for the star tree writer */
+    public static final int VERSION_CURRENT = VERSION_START;
+
+    private StarTreeWriter() {}
+
+    /**
+     * Write star tree to index output stream
+     *
+     * @param dataOut  data index output
+     * @param rootNode root star-tree node
+     * @param numNodes number of nodes in the tree
+     * @param name     name of the star-tree field
+     * @return total size of the three
+     * @throws IOException when star-tree data serialization fails
+     */
+    public static long writeStarTree(IndexOutput dataOut, InMemoryTreeNode rootNode, int numNodes, String name) throws IOException {
+        return StarTreeDataWriter.writeStarTree(dataOut, rootNode, numNodes, name);
+    }
+
+    /**
+     * Write star tree metadata to index output stream
+     *
+     * @param metaOut                meta index output
+     * @param starTreeField          star tree field
+     * @param metricAggregatorInfos  metric aggregator infos
+     * @param segmentAggregatedCount segment aggregated count
+     * @param dataFilePointer        data file pointer
+     * @param dataFileLength         data file length
+     * @throws IOException when star-tree data serialization fails
+     */
+    public static void writeStarTreeMetadata(
+        IndexOutput metaOut,
+        StarTreeField starTreeField,
+        List<MetricAggregatorInfo> metricAggregatorInfos,
+        Integer segmentAggregatedCount,
+        long dataFilePointer,
+        long dataFileLength
+    ) throws IOException {
+        StarTreeMetaWriter.writeStarTreeMetadata(
+            metaOut,
+            starTreeField,
+            metricAggregatorInfos,
+            segmentAggregatedCount,
+            dataFilePointer,
+            dataFileLength
+        );
+    }
+
+}