Adding more functionality to analyze endpoint

core/src/main/java/org/opensearch/sql/calcite/CalcitePlanContext.java

@@ -46,6 +46,10 @@ public class CalcitePlanContext {
   /** This thread local variable is only used to skip script encoding in script pushdown. */
   public static final ThreadLocal<Boolean> skipEncoding = ThreadLocal.withInitial(() -> false);
 
+  /** When true, disables the OpenSearch shard request cache for the current query. */
+  public static final ThreadLocal<Boolean> disableRequestCache =
+      ThreadLocal.withInitial(() -> false);
+
   /** When true, the execution engine strips all-null columns from the result (used by timewrap). */
   public static final ThreadLocal<Boolean> stripNullColumns = ThreadLocal.withInitial(() -> false);
 

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

@@ -21,11 +21,12 @@ public class AnalyzeResponse {
   private final List<String> physicalPlan;
   private final QueryProfile profile;
   private final List<OperatorNode> operator_tree;
-  private final List<String> recommendations;
+  private final List<Recommendation> recommendations;
   private final List<SchemaColumn> schema;
   private final Object[][] datarows;
   private final long total;
   private final long size;
+  private final boolean possibleCacheHit;
 
   @Data
   @Builder
@@ -46,11 +47,28 @@ public static class QuerySegment {
   public static class OperatorNode {
     private final String source;
     private final List<String> node_type;
+    private final List<Float> node_cost;
     private final List<String> description;
     private final String estimated_cost;
     private final Long estimated_rows;
     private final String actual_time_ms;
     private final Long actual_rows;
     private final Boolean is_pushed_down;
   }
+
+  public enum RecommendationSeverityLevel {
+    INFO,
+    WARNING,
+    CRITICAL
+  }
+
+  @Data
+  @Builder
+  public static class Recommendation {
+    private final RecommendationSeverityLevel serverity;
+    private final String rule;
+    private final String message;
+    private final String affected_node;
+    private final String suggestion;
+  }
 }

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

@@ -86,6 +86,14 @@ default void explain(
     explain(plan, mode, context, listener);
   }
 
+  /**
+   * Get the cumulative request cache hit count for the given indices. Returns -1 if not supported
+   * by this engine.
+   */
+  default long getRequestCacheHitCount(String... indexNames) {
+    return -1;
+  }
+
   /** Data class that encapsulates ExprValue. */
   @Data
   class QueryResponse {