Support for pagination in v2 engine of SELECT * FROM <table> queries (

opensearch-project#1666)

v2 SQL engine can now paginate simple queries. Pagination is initiated by setting fetch_size property in the request JSON.

Pagination is implemented using the OpenSearch Scroll API. Please see pagination-v2.md for implementation details.
---------

Signed-off-by: MaxKsyunz <maxk@bitquilltech.com>
Signed-off-by: Yury-Fridlyand <yury.fridlyand@improving.com>
Signed-off-by: Max Ksyunz <maxk@bitquilltech.com>
Co-authored-by: Yury-Fridlyand <yury.fridlyand@improving.com>
Co-authored-by: GabeFernandez310 <Gabriel.Fernandez@improving.com>
Co-authored-by: Andrew Carbonetto <andrewc@bitquilltech.com>

core/build.gradle

@@ -57,6 +57,7 @@ dependencies {
     testImplementation('org.junit.jupiter:junit-jupiter:5.6.2')
     testImplementation group: 'org.hamcrest', name: 'hamcrest-library', version: '2.1'
     testImplementation group: 'org.mockito', name: 'mockito-core', version: '3.12.4'
+    testImplementation group: 'org.mockito', name: 'mockito-inline', version: '3.12.4'
     testImplementation group: 'org.mockito', name: 'mockito-junit-jupiter', version: '3.12.4'
 }
 

core/src/main/java/org/opensearch/sql/analysis/Analyzer.java

@@ -6,6 +6,7 @@
 
 package org.opensearch.sql.analysis;
 
+import static org.opensearch.sql.analysis.DataSourceSchemaIdentifierNameResolver.DEFAULT_DATASOURCE_NAME;
 import static org.opensearch.sql.ast.tree.Sort.NullOrder.NULL_FIRST;
 import static org.opensearch.sql.ast.tree.Sort.NullOrder.NULL_LAST;
 import static org.opensearch.sql.ast.tree.Sort.SortOrder.ASC;
@@ -42,13 +43,16 @@
 import org.opensearch.sql.ast.expression.UnresolvedExpression;
 import org.opensearch.sql.ast.tree.AD;
 import org.opensearch.sql.ast.tree.Aggregation;
+import org.opensearch.sql.ast.tree.CloseCursor;
 import org.opensearch.sql.ast.tree.Dedupe;
 import org.opensearch.sql.ast.tree.Eval;
+import org.opensearch.sql.ast.tree.FetchCursor;
 import org.opensearch.sql.ast.tree.Filter;
 import org.opensearch.sql.ast.tree.Head;
 import org.opensearch.sql.ast.tree.Kmeans;
 import org.opensearch.sql.ast.tree.Limit;
 import org.opensearch.sql.ast.tree.ML;
+import org.opensearch.sql.ast.tree.Paginate;
 import org.opensearch.sql.ast.tree.Parse;
 import org.opensearch.sql.ast.tree.Project;
 import org.opensearch.sql.ast.tree.RareTopN;
@@ -80,12 +84,15 @@
 import org.opensearch.sql.expression.parse.ParseExpression;
 import org.opensearch.sql.planner.logical.LogicalAD;
 import org.opensearch.sql.planner.logical.LogicalAggregation;
+import org.opensearch.sql.planner.logical.LogicalCloseCursor;
 import org.opensearch.sql.planner.logical.LogicalDedupe;
 import org.opensearch.sql.planner.logical.LogicalEval;
+import org.opensearch.sql.planner.logical.LogicalFetchCursor;
 import org.opensearch.sql.planner.logical.LogicalFilter;
 import org.opensearch.sql.planner.logical.LogicalLimit;
 import org.opensearch.sql.planner.logical.LogicalML;
 import org.opensearch.sql.planner.logical.LogicalMLCommons;
+import org.opensearch.sql.planner.logical.LogicalPaginate;
 import org.opensearch.sql.planner.logical.LogicalPlan;
 import org.opensearch.sql.planner.logical.LogicalProject;
 import org.opensearch.sql.planner.logical.LogicalRareTopN;
@@ -208,7 +215,6 @@ public LogicalPlan visitTableFunction(TableFunction node, AnalysisContext contex
         tableFunctionImplementation.applyArguments());
   }
 
-
   @Override
   public LogicalPlan visitLimit(Limit node, AnalysisContext context) {
     LogicalPlan child = node.getChild().get(0).accept(this, context);
@@ -561,6 +567,23 @@ public LogicalPlan visitML(ML node, AnalysisContext context) {
     return new LogicalML(child, node.getArguments());
   }
 
+  @Override
+  public LogicalPlan visitPaginate(Paginate paginate, AnalysisContext context) {
+    LogicalPlan child = paginate.getChild().get(0).accept(this, context);
+    return new LogicalPaginate(paginate.getPageSize(), List.of(child));
+  }
+
+  @Override
+  public LogicalPlan visitFetchCursor(FetchCursor cursor, AnalysisContext context) {
+    return new LogicalFetchCursor(cursor.getCursor(),
+      dataSourceService.getDataSource(DEFAULT_DATASOURCE_NAME).getStorageEngine());
+  }
+
+  @Override
+  public LogicalPlan visitCloseCursor(CloseCursor closeCursor, AnalysisContext context) {
+    return new LogicalCloseCursor(closeCursor.getChild().get(0).accept(this, context));
+  }
+
   /**
    * The first argument is always "asc", others are optional.
    * Given nullFirst argument, use its value. Otherwise just use DEFAULT_ASC/DESC.
@@ -576,5 +599,4 @@ private SortOption analyzeSortOption(List<Argument> fieldArgs) {
     }
     return asc ? SortOption.DEFAULT_ASC : SortOption.DEFAULT_DESC;
   }
-
 }

core/src/main/java/org/opensearch/sql/ast/AbstractNodeVisitor.java

@@ -41,13 +41,16 @@
 import org.opensearch.sql.ast.statement.Statement;
 import org.opensearch.sql.ast.tree.AD;
 import org.opensearch.sql.ast.tree.Aggregation;
+import org.opensearch.sql.ast.tree.CloseCursor;
 import org.opensearch.sql.ast.tree.Dedupe;
 import org.opensearch.sql.ast.tree.Eval;
+import org.opensearch.sql.ast.tree.FetchCursor;
 import org.opensearch.sql.ast.tree.Filter;
 import org.opensearch.sql.ast.tree.Head;
 import org.opensearch.sql.ast.tree.Kmeans;
 import org.opensearch.sql.ast.tree.Limit;
 import org.opensearch.sql.ast.tree.ML;
+import org.opensearch.sql.ast.tree.Paginate;
 import org.opensearch.sql.ast.tree.Parse;
 import org.opensearch.sql.ast.tree.Project;
 import org.opensearch.sql.ast.tree.RareTopN;
@@ -294,4 +297,16 @@ public T visitQuery(Query node, C context) {
   public T visitExplain(Explain node, C context) {
     return visitStatement(node, context);
   }
+
+  public T visitPaginate(Paginate paginate, C context) {
+    return visitChildren(paginate, context);
+  }
+
+  public T visitFetchCursor(FetchCursor cursor, C context) {
+    return visitChildren(cursor, context);
+  }
+
+  public T visitCloseCursor(CloseCursor closeCursor, C context) {
+    return visitChildren(closeCursor, context);
+  }
 }

core/src/main/java/org/opensearch/sql/ast/statement/Query.java

@@ -27,6 +27,7 @@
 public class Query extends Statement {
 
   protected final UnresolvedPlan plan;
+  protected final int fetchSize;
 
   @Override
   public <R, C> R accept(AbstractNodeVisitor<R, C> visitor, C context) {

core/src/main/java/org/opensearch/sql/ast/tree/CloseCursor.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.sql.ast.tree;
+
+import java.util.List;
+import org.opensearch.sql.ast.AbstractNodeVisitor;
+import org.opensearch.sql.ast.Node;
+
+/**
+ * AST node to represent close cursor operation.
+ * Actually a wrapper to the AST.
+ */
+public class CloseCursor extends UnresolvedPlan {
+
+  /**
+   * An instance of {@link FetchCursor}.
+   */
+  private UnresolvedPlan cursor;
+
+  @Override
+  public <T, C> T accept(AbstractNodeVisitor<T, C> nodeVisitor, C context) {
+    return nodeVisitor.visitCloseCursor(this, context);
+  }
+
+  @Override
+  public UnresolvedPlan attach(UnresolvedPlan child) {
+    this.cursor = child;
+    return this;
+  }
+
+  @Override
+  public List<? extends Node> getChild() {
+    return List.of(cursor);
+  }
+}

core/src/main/java/org/opensearch/sql/ast/tree/FetchCursor.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.sql.ast.tree;
+
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.opensearch.sql.ast.AbstractNodeVisitor;
+
+/**
+ * An unresolved plan that represents fetching the next
+ * batch in paginationed plan.
+ */
+@RequiredArgsConstructor
+@EqualsAndHashCode(callSuper = false)
+public class FetchCursor extends UnresolvedPlan {
+  @Getter
+  final String cursor;
+
+  @Override
+  public <T, C> T accept(AbstractNodeVisitor<T, C> nodeVisitor, C context) {
+    return nodeVisitor.visitFetchCursor(this, context);
+  }
+
+  @Override
+  public UnresolvedPlan attach(UnresolvedPlan child) {
+    throw new UnsupportedOperationException("Cursor unresolved plan does not support children");
+  }
+}

core/src/main/java/org/opensearch/sql/ast/tree/Paginate.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.sql.ast.tree;
+
+import java.util.List;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import lombok.ToString;
+import org.opensearch.sql.ast.AbstractNodeVisitor;
+import org.opensearch.sql.ast.Node;
+
+/**
+ * AST node to represent pagination operation.
+ * Actually a wrapper to the AST.
+ */
+@RequiredArgsConstructor
+@EqualsAndHashCode(callSuper = false)
+@ToString
+public class Paginate extends UnresolvedPlan {
+  @Getter
+  private final int pageSize;
+  private UnresolvedPlan child;
+
+  public Paginate(int pageSize, UnresolvedPlan child) {
+    this.pageSize = pageSize;
+    this.child = child;
+  }
+
+  @Override
+  public List<? extends Node> getChild() {
+    return List.of(child);
+  }
+
+  @Override
+  public <T, C> T accept(AbstractNodeVisitor<T, C> nodeVisitor, C context) {
+    return nodeVisitor.visitPaginate(this, context);
+  }
+
+  @Override
+  public UnresolvedPlan attach(UnresolvedPlan child) {
+    this.child = child;
+    return this;
+  }
+}

core/src/main/java/org/opensearch/sql/exception/NoCursorException.java

@@ -0,0 +1,13 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.sql.exception;
+
+/**
+ * This should be thrown on serialization of a PhysicalPlan tree if paging is finished.
+ * Processing of such exception should outcome of responding no cursor to the user.
+ */
+public class NoCursorException extends RuntimeException {
+}

core/src/main/java/org/opensearch/sql/exception/UnsupportedCursorRequestException.java

@@ -0,0 +1,12 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.sql.exception;
+
+/**
+ * This should be thrown by V2 engine to support fallback scenario.
+ */
+public class UnsupportedCursorRequestException extends RuntimeException {
+}

core/src/main/java/org/opensearch/sql/executor/ExecutionEngine.java

@@ -14,6 +14,7 @@
 import org.opensearch.sql.common.response.ResponseListener;
 import org.opensearch.sql.data.model.ExprValue;
 import org.opensearch.sql.data.type.ExprType;
+import org.opensearch.sql.executor.pagination.Cursor;
 import org.opensearch.sql.planner.physical.PhysicalPlan;
 
 /**
@@ -53,6 +54,7 @@ void execute(PhysicalPlan plan, ExecutionContext context,
   class QueryResponse {
     private final Schema schema;
     private final List<ExprValue> results;
+    private final Cursor cursor;
   }
 
   @Data

core/src/main/java/org/opensearch/sql/executor/execution/CommandPlan.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.sql.executor.execution;
+
+import org.opensearch.sql.ast.tree.UnresolvedPlan;
+import org.opensearch.sql.common.response.ResponseListener;
+import org.opensearch.sql.executor.ExecutionEngine;
+import org.opensearch.sql.executor.QueryId;
+import org.opensearch.sql.executor.QueryService;
+
+/**
+ * Query plan which does not reflect a search query being executed.
+ * It contains a command or an action, for example, a DDL query.
+ */
+public class CommandPlan extends AbstractPlan {
+
+  /**
+   * The query plan ast.
+   */
+  protected final UnresolvedPlan plan;
+
+  /**
+   * Query service.
+   */
+  protected final QueryService queryService;
+
+  protected final ResponseListener<ExecutionEngine.QueryResponse> listener;
+
+  /** Constructor. */
+  public CommandPlan(QueryId queryId, UnresolvedPlan plan, QueryService queryService,
+                     ResponseListener<ExecutionEngine.QueryResponse> listener) {
+    super(queryId);
+    this.plan = plan;
+    this.queryService = queryService;
+    this.listener = listener;
+  }
+
+  @Override
+  public void execute() {
+    queryService.execute(plan, listener);
+  }
+
+  @Override
+  public void explain(ResponseListener<ExecutionEngine.ExplainResponse> listener) {
+    throw new UnsupportedOperationException("CommandPlan does not support explain");
+  }
+}