Store exception messages when using %%gremlin --store-to

ChangeLog.md

@@ -4,6 +4,7 @@ Starting with v1.31.6, this file will contain a record of major features and upd
 
 ## Upcoming
 - Added `--connected-table` option to magics with table widget output ([Link to PR](https://github.com/aws/graph-notebook/pull/634))
+- Changed `%%gremlin --store-to` to also store exceptions from non-Neptune queries ([Link to PR](https://github.com/aws/graph-notebook/pull/635))
 - Fixed broken `--help` option for `%%gremlin` ([Link to PR](https://github.com/aws/graph-notebook/pull/630))
 - Fixed openCypher query bug regression in the [`01-About-the-Neptune-Notebook`](https://github.com/aws/graph-notebook/blob/main/src/graph_notebook/notebooks/01-Getting-Started/01-About-the-Neptune-Notebook.ipynb) sample ([Link to PR](https://github.com/aws/graph-notebook/pull/631))
 - Fixed `%%graph_notebook_config` error when excluding optional Gremlin section ([Link to PR](https://github.com/aws/graph-notebook/pull/633))

src/graph_notebook/magics/graph_magic.py

@@ -1216,7 +1216,11 @@ def gremlin(self, line, cell, local_ns: dict = None):
                         print("%%gremlin is incompatible with Neptune Analytics.")
                     raise e
             else:
-                query_res = self.client.gremlin_query(cell, transport_args=transport_args)
+                try:
+                    query_res = self.client.gremlin_query(cell, transport_args=transport_args)
+                except Exception as e:
+                    store_to_ns(args.store_to, {'error': str(e)[5:]}, local_ns)  # remove the leading error code.
+                    raise e
             query_time = time.time() * 1000 - query_start
             if not args.silent:
                 gremlin_metadata = build_gremlin_metadata_from_query(query_type='query', results=query_res,