fix: dataframes to_gbq now creates dataset if it doesn't exist (#222)

* "fix: dataframes to_gbq now creates dataset if it doesn't exist

* fix: dataframes to_gbq now creates dataset if it doesn't exist

* fix: dataframes to_gbq now creates dataset if it doesn't exist

* update test

* update create dataset method.

* fix

---------

Co-authored-by: Shobhit Singh <shobs@google.com>

Author: Genesis929

bigframes/dataframe.py

@@ -34,6 +34,7 @@
     Union,
 )
 
+import google.api_core.exceptions
 import google.cloud.bigquery as bigquery
 import numpy
 import pandas
@@ -2508,7 +2509,14 @@ def to_gbq(
                 )
             if_exists = "replace"
 
-        if "." not in destination_table:
+        table_parts = destination_table.split(".")
+        default_project = self._block.expr.session.bqclient.project
+
+        if len(table_parts) == 2:
+            destination_dataset = f"{default_project}.{table_parts[0]}"
+        elif len(table_parts) == 3:
+            destination_dataset = f"{table_parts[0]}.{table_parts[1]}"
+        else:
             raise ValueError(
                 f"Got invalid value for destination_table {repr(destination_table)}. "
                 "Should be of the form 'datasetId.tableId' or 'projectId.datasetId.tableId'."
@@ -2523,11 +2531,16 @@ def to_gbq(
                 f"Valid options include None or one of {dispositions.keys()}."
             )
 
+        try:
+            self._session.bqclient.get_dataset(destination_dataset)
+        except google.api_core.exceptions.NotFound:
+            self._session.bqclient.create_dataset(destination_dataset, exists_ok=True)
+
         job_config = bigquery.QueryJobConfig(
             write_disposition=dispositions[if_exists],
             destination=bigquery.table.TableReference.from_string(
                 destination_table,
-                default_project=self._block.expr.session.bqclient.project,
+                default_project=default_project,
             ),
         )
 

tests/system/small/test_dataframe.py

@@ -3683,3 +3683,18 @@ def test_to_pandas_downsampling_option_override(session):
     total_memory_bytes = df.memory_usage(deep=True).sum()
     total_memory_mb = total_memory_bytes / (1024 * 1024)
     assert total_memory_mb == pytest.approx(download_size, rel=0.3)
+
+
+def test_to_gbq_and_create_dataset(session, scalars_df_index, dataset_id_not_created):
+    dataset_id = dataset_id_not_created
+    destination_table = f"{dataset_id}.scalars_df"
+
+    result_table = scalars_df_index.to_gbq(destination_table)
+    assert (
+        result_table == destination_table
+        if destination_table
+        else result_table is not None
+    )
+
+    loaded_scalars_df_index = session.read_gbq(result_table)
+    assert not loaded_scalars_df_index.empty