iterator: Add get_column_specs() to RowIterator

QueryResult has a field called col_specs which
contains information about the selected columns.

Make the same information avaialble when using an iterator.

Signed-off-by: Jan Ciolek <[email protected]>

scylla/src/transport/iterator.rs

@@ -18,7 +18,7 @@ use crate::cql_to_rust::{FromRow, FromRowError};
 use crate::frame::{
     response::{
         result,
-        result::{Row, Rows},
+        result::{ColumnSpec, Row, Rows},
         Response,
     },
     value::SerializedValues,
@@ -212,6 +212,11 @@ impl RowIterator {
         &self.warnings
     }
 
+    /// Returns specification of row columns
+    pub fn get_column_specs(&self) -> &[ColumnSpec] {
+        &self.current_page.metadata.col_specs
+    }
+
     fn is_current_page_exhausted(&self) -> bool {
         self.current_row_idx >= self.current_page.rows.len()
     }
@@ -371,6 +376,11 @@ impl<RowT> TypedRowIterator<RowT> {
     pub fn get_warnings(&self) -> &[String] {
         self.row_iterator.get_warnings()
     }
+
+    /// Returns specification of row columns
+    pub fn get_column_specs(&self) -> &[ColumnSpec] {
+        self.row_iterator.get_column_specs()
+    }
 }
 
 /// Couldn't get next typed row from the iterator