Improve performance of _convert_arrow_to_proto

_convert_arrow_to_proto does multiple lookups in the list of column
names for the arrow table to find the index of columns. This is done for
each row so the time complexity grows quickly.
Rather than search the list of names for the index we construct a
dictionary {column_name: index}. This allows faster lookups for the
index of a column and speeds up the method significantly which affects
e.g. materialization.

Signed-off-by: Gunnar Sv Sigurbjörnsson <[email protected]>

sdk/python/feast/infra/provider.py

@@ -304,27 +304,28 @@ def _coerce_datetime(ts):
         else:
             return ts
 
+    column_names_idx = {k: i for i, k in enumerate(table.column_names)}
     for row in zip(*table.to_pydict().values()):
         entity_key = EntityKeyProto()
         for join_key in join_keys:
             entity_key.join_keys.append(join_key)
-            idx = table.column_names.index(join_key)
+            idx = column_names_idx[join_key]
             value = python_value_to_proto_value(row[idx])
             entity_key.entity_values.append(value)
         feature_dict = {}
         for feature in feature_view.features:
-            idx = table.column_names.index(feature.name)
+            idx = column_names_idx[feature.name]
             value = python_value_to_proto_value(row[idx], feature.dtype)
             feature_dict[feature.name] = value
-        event_timestamp_idx = table.column_names.index(
+        event_timestamp_idx = column_names_idx[
             feature_view.batch_source.event_timestamp_column
-        )
+        ]
         event_timestamp = _coerce_datetime(row[event_timestamp_idx])
 
         if feature_view.batch_source.created_timestamp_column:
-            created_timestamp_idx = table.column_names.index(
+            created_timestamp_idx = column_names_idx[
                 feature_view.batch_source.created_timestamp_column
-            )
+            ]
             created_timestamp = _coerce_datetime(row[created_timestamp_idx])
         else:
             created_timestamp = None