deps: require pyarrow for pandas support (#314)

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Fixes #265 🦕

Author: cguardia

docs/snippets.py

@@ -26,10 +26,6 @@
 
 import pytest
 
-try:
-    import fastparquet
-except (ImportError, AttributeError):
-    fastparquet = None
 try:
     import pandas
 except (ImportError, AttributeError):

google/cloud/bigquery/__init__.py

@@ -38,7 +38,6 @@
 from google.cloud.bigquery.dataset import DatasetReference
 from google.cloud.bigquery import enums
 from google.cloud.bigquery.enums import StandardSqlDataTypes
-from google.cloud.bigquery.exceptions import PyarrowMissingWarning
 from google.cloud.bigquery.external_config import ExternalConfig
 from google.cloud.bigquery.external_config import BigtableOptions
 from google.cloud.bigquery.external_config import BigtableColumnFamily
@@ -143,8 +142,6 @@
     "WriteDisposition",
     # EncryptionConfiguration
     "EncryptionConfiguration",
-    # Errors and warnings
-    "PyarrowMissingWarning",
 ]
 
 

google/cloud/bigquery/client.py

@@ -58,7 +58,6 @@
 from google.cloud.bigquery.dataset import Dataset
 from google.cloud.bigquery.dataset import DatasetListItem
 from google.cloud.bigquery.dataset import DatasetReference
-from google.cloud.bigquery.exceptions import PyarrowMissingWarning
 from google.cloud.bigquery.opentelemetry_tracing import create_span
 from google.cloud.bigquery import job
 from google.cloud.bigquery.model import Model
@@ -2135,29 +2134,31 @@ def load_table_from_dataframe(
                  [Beta] The compression method to use if intermittently
                  serializing ``dataframe`` to a parquet file.
 
-                 If ``pyarrow`` and job config schema are used, the argument
-                 is directly passed as the ``compression`` argument to the
-                 underlying ``pyarrow.parquet.write_table()`` method (the
-                 default value "snappy" gets converted to uppercase).
+                 The argument is directly passed as the ``compression``
+                 argument to the underlying ``pyarrow.parquet.write_table()``
+                 method (the default value "snappy" gets converted to uppercase).
                  https://arrow.apache.org/docs/python/generated/pyarrow.parquet.write_table.html#pyarrow-parquet-write-table
 
-                 If either ``pyarrow`` or job config schema are missing, the
-                 argument is directly passed as the ``compression`` argument
-                 to the underlying ``DataFrame.to_parquet()`` method.
+                 If the job config schema is missing, the argument is directly
+                 passed as the ``compression`` argument to the underlying
+                 ``DataFrame.to_parquet()`` method.
                  https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.to_parquet.html#pandas.DataFrame.to_parquet
 
         Returns:
             google.cloud.bigquery.job.LoadJob: A new load job.
 
         Raises:
-            ImportError:
+            ValueError:
                 If a usable parquet engine cannot be found. This method
-                requires :mod:`pyarrow` or :mod:`fastparquet` to be
-                installed.
+                requires :mod:`pyarrow` to be installed.
             TypeError:
                 If ``job_config`` is not an instance of :class:`~google.cloud.bigquery.job.LoadJobConfig`
                 class.
         """
+        if pyarrow is None:
+            # pyarrow is now the only supported  parquet engine.
+            raise ValueError("This method requires pyarrow to be installed")
+
         job_id = _make_job_id(job_id, job_id_prefix)
 
         if job_config:
@@ -2222,7 +2223,7 @@ def load_table_from_dataframe(
         os.close(tmpfd)
 
         try:
-            if pyarrow and job_config.schema:
+            if job_config.schema:
                 if parquet_compression == "snappy":  # adjust the default value
                     parquet_compression = parquet_compression.upper()
 
@@ -2233,24 +2234,6 @@ def load_table_from_dataframe(
                     parquet_compression=parquet_compression,
                 )
             else:
-                if not pyarrow:
-                    warnings.warn(
-                        "Loading dataframe data without pyarrow installed is "
-                        "deprecated and will become unsupported in the future. "
-                        "Please install the pyarrow package.",
-                        PyarrowMissingWarning,
-                        stacklevel=2,
-                    )
-
-                if job_config.schema:
-                    warnings.warn(
-                        "job_config.schema is set, but not used to assist in "
-                        "identifying correct types for data serialization. "
-                        "Please install the pyarrow package.",
-                        PendingDeprecationWarning,
-                        stacklevel=2,
-                    )
-
                 dataframe.to_parquet(tmppath, compression=parquet_compression)
 
             with open(tmppath, "rb") as parquet_file:

google/cloud/bigquery/exceptions.py

@@ -50,7 +50,6 @@
 from google.cloud.bigquery.schema import _build_schema_resource
 from google.cloud.bigquery.schema import _parse_schema_resource
 from google.cloud.bigquery.schema import _to_schema_fields
-from google.cloud.bigquery.exceptions import PyarrowMissingWarning
 from google.cloud.bigquery.external_config import ExternalConfig
 from google.cloud.bigquery.encryption_configuration import EncryptionConfiguration
 
@@ -1679,75 +1678,38 @@ def to_dataframe(
             create_bqstorage_client = False
             bqstorage_client = None
 
-        if pyarrow is not None:
-            # If pyarrow is available, calling to_arrow, then converting to a
-            # pandas dataframe is about 2x faster. This is because pandas.concat is
-            # rarely no-copy, whereas pyarrow.Table.from_batches + to_pandas is
-            # usually no-copy.
-            record_batch = self.to_arrow(
-                progress_bar_type=progress_bar_type,
-                bqstorage_client=bqstorage_client,
-                create_bqstorage_client=create_bqstorage_client,
-            )
+        record_batch = self.to_arrow(
+            progress_bar_type=progress_bar_type,
+            bqstorage_client=bqstorage_client,
+            create_bqstorage_client=create_bqstorage_client,
+        )
+
+        # When converting timestamp values to nanosecond precision, the result
+        # can be out of pyarrow bounds. To avoid the error when converting to
+        # Pandas, we set the timestamp_as_object parameter to True, if necessary.
+        types_to_check = {
+            pyarrow.timestamp("us"),
+            pyarrow.timestamp("us", tz=pytz.UTC),
+        }
 
-            # When converting timestamp values to nanosecond precision, the result
-            # can be out of pyarrow bounds. To avoid the error when converting to
-            # Pandas, we set the timestamp_as_object parameter to True, if necessary.
-            types_to_check = {
-                pyarrow.timestamp("us"),
-                pyarrow.timestamp("us", tz=pytz.UTC),
-            }
-
-            for column in record_batch:
-                if column.type in types_to_check:
-                    try:
-                        column.cast("timestamp[ns]")
-                    except pyarrow.lib.ArrowInvalid:
-                        timestamp_as_object = True
-                        break
-            else:
-                timestamp_as_object = False
-
-            extra_kwargs = {"timestamp_as_object": timestamp_as_object}
-
-            df = record_batch.to_pandas(date_as_object=date_as_object, **extra_kwargs)
-
-            for column in dtypes:
-                df[column] = pandas.Series(df[column], dtype=dtypes[column])
-            return df
+        for column in record_batch:
+            if column.type in types_to_check:
+                try:
+                    column.cast("timestamp[ns]")
+                except pyarrow.lib.ArrowInvalid:
+                    timestamp_as_object = True
+                    break
         else:
-            warnings.warn(
-                "Converting to a dataframe without pyarrow installed is "
-                "often slower and will become unsupported in the future. "
-                "Please install the pyarrow package.",
-                PyarrowMissingWarning,
-                stacklevel=2,
-            )
+            timestamp_as_object = False
 
-        # The bqstorage_client is only used if pyarrow is available, so the
-        # rest of this method only needs to account for tabledata.list.
-        progress_bar = self._get_progress_bar(progress_bar_type)
+        extra_kwargs = {"timestamp_as_object": timestamp_as_object}
 
-        frames = []
-        for frame in self.to_dataframe_iterable(dtypes=dtypes):
-            frames.append(frame)
+        df = record_batch.to_pandas(date_as_object=date_as_object, **extra_kwargs)
 
-            if progress_bar is not None:
-                # In some cases, the number of total rows is not populated
-                # until the first page of rows is fetched. Update the
-                # progress bar's total to keep an accurate count.
-                progress_bar.total = progress_bar.total or self.total_rows
-                progress_bar.update(len(frame))
-
-        if progress_bar is not None:
-            # Indicate that the download has finished.
-            progress_bar.close()
-
-        # Avoid concatting an empty list.
-        if not frames:
-            column_names = [field.name for field in self._schema]
-            return pandas.DataFrame(columns=column_names)
-        return pandas.concat(frames, ignore_index=True)
+        for column in dtypes:
+            df[column] = pandas.Series(df[column], dtype=dtypes[column])
+
+        return df
 
 
 class _EmptyRowIterator(object):

google/cloud/bigquery/table.py

@@ -49,10 +49,7 @@ def default(session):
         constraints_path,
     )
 
-    # fastparquet is not included in .[all] because, in general, it's
-    # redundant with pyarrow. We still want to run some unit tests with
-    # fastparquet serialization, though.
-    session.install("-e", ".[all,fastparquet]", "-c", constraints_path)
+    session.install("-e", ".[all]", "-c", constraints_path)
 
     session.install("ipython", "-c", constraints_path)
 

noxfile.py

@@ -47,13 +47,12 @@
         "grpcio >= 1.32.0, < 2.0dev",
         "pyarrow >= 1.0.0, < 2.0dev",
     ],
-    "pandas": ["pandas>=0.23.0"],
-    "pyarrow": [
+    "pandas": [
+        "pandas>=0.23.0",
         # pyarrow 1.0.0 is required for the use of timestamp_as_object keyword.
         "pyarrow >= 1.0.0, < 2.0dev",
     ],
     "tqdm": ["tqdm >= 4.7.4, <5.0.0dev"],
-    "fastparquet": ["fastparquet", "python-snappy", "llvmlite>=0.34.0"],
     "opentelemetry": [
         "opentelemetry-api==0.9b0",
         "opentelemetry-sdk==0.9b0",
@@ -64,13 +63,6 @@
 all_extras = []
 
 for extra in extras:
-    if extra in (
-        # Skip fastparquet from "all" because it is redundant with pyarrow and
-        # creates a dependency on pre-release versions of numpy. See:
-        # https://github.com/googleapis/google-cloud-python/issues/8549
-        "fastparquet",
-    ):
-        continue
     all_extras.extend(extras[extra])
 
 extras["all"] = all_extras

setup.py

@@ -1,4 +1,3 @@
-fastparquet==0.4.1
 google-api-core==1.22.2
 google-cloud-bigquery-storage==2.0.0
 google-cloud-core==1.4.1

testing/constraints-3.6.txt

@@ -1329,3 +1329,11 @@ def test_download_dataframe_tabledata_list_dict_sequence_schema(module_under_tes
         )
     )
     assert result.equals(expected_result)
+
+    with pytest.raises(StopIteration):
+        result = next(results_gen)
+
+
+def test_table_data_listpage_to_dataframe_skips_stop_iteration(module_under_test):
+    dataframe = module_under_test._tabledata_list_page_to_dataframe([], [], {})
+    assert isinstance(dataframe, pandas.DataFrame)