From bd260822f9452d982000cd88d79749aa4616eadf Mon Sep 17 00:00:00 2001
From: Tim Swast <swast@google.com>
Date: Fri, 2 Jul 2021 13:01:12 -0500
Subject: [PATCH 1/3] feat: add LoadJobConfig.projection_fields to select
 DATASTORE_BACKUP fields

---
 google/cloud/bigquery/job/load.py  | 21 +++++++++++++++++++++
 tests/unit/job/test_load_config.py | 11 +++++++++++
 2 files changed, 32 insertions(+)

diff --git a/google/cloud/bigquery/job/load.py b/google/cloud/bigquery/job/load.py
index 41d38dd74..5e8e3dab2 100644
--- a/google/cloud/bigquery/job/load.py
+++ b/google/cloud/bigquery/job/load.py
@@ -277,6 +277,27 @@ def null_marker(self):
     def null_marker(self, value):
         self._set_sub_prop("nullMarker", value)
 
+    @property
+    def projection_fields(self):
+        """Optional[List[str]]: If
+        :attr:`google.cloud.bigquery.job.LoadJobConfig.source_format` is set to
+        "DATASTORE_BACKUP", indicates which entity properties to load into
+        BigQuery from a Cloud Datastore backup.
+
+        Property names are case sensitive and must be top-level properties. If
+        no properties are specified, BigQuery loads all properties. If any
+        named property isn't found in the Cloud Datastore backup, an invalid
+        error is returned in the job result.
+
+        See:
+        https://cloud.google.com/bigquery/docs/reference/rest/v2/Job#JobConfigurationLoad.FIELDS.projection_fields
+        """
+        return self._get_sub_prop("projectionFields")
+
+    @projection_fields.setter
+    def projection_fields(self, value):
+        self._set_sub_prop("projectionFields", value)
+
     @property
     def quote_character(self):
         """Optional[str]: Character used to quote data sections (CSV only).
diff --git a/tests/unit/job/test_load_config.py b/tests/unit/job/test_load_config.py
index eafe7e046..2e7ea75c1 100644
--- a/tests/unit/job/test_load_config.py
+++ b/tests/unit/job/test_load_config.py
@@ -385,6 +385,17 @@ def test_null_marker_setter(self):
         config.null_marker = null_marker
         self.assertEqual(config._properties["load"]["nullMarker"], null_marker)
 
+    def test_projection_fields_miss(self):
+        config = self._get_target_class()()
+        self.assertIsNone(config.projection_fields)
+
+    def test_projection_fields_hit(self):
+        config = self._get_target_class()()
+        fields = ["email", "postal_code"]
+        config.projection_fields = fields
+        self.assertEqual(config._properties["load"]["projectionFields"], fields)
+        self.assertEqual(config.projection_fields, fields)
+
     def test_quote_character_missing(self):
         config = self._get_target_class()()
         self.assertIsNone(config.quote_character)

From 354c42cd4d70b4fe6934eef27b7420e8af8e61c0 Mon Sep 17 00:00:00 2001
From: Tim Swast <swast@google.com>
Date: Fri, 9 Jul 2021 13:52:46 -0500
Subject: [PATCH 2/3] add type annotations

---
 google/cloud/bigquery/job/load.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/google/cloud/bigquery/job/load.py b/google/cloud/bigquery/job/load.py
index 5e8e3dab2..bedc33f32 100644
--- a/google/cloud/bigquery/job/load.py
+++ b/google/cloud/bigquery/job/load.py
@@ -14,6 +14,8 @@
 
 """Classes for load jobs."""
 
+from typing import Optional, List
+
 from google.cloud.bigquery.encryption_configuration import EncryptionConfiguration
 from google.cloud.bigquery.external_config import HivePartitioningOptions
 from google.cloud.bigquery.format_options import ParquetOptions
@@ -23,7 +25,6 @@
 from google.cloud.bigquery.table import RangePartitioning
 from google.cloud.bigquery.table import TableReference
 from google.cloud.bigquery.table import TimePartitioning
-
 from google.cloud.bigquery.job.base import _AsyncJob
 from google.cloud.bigquery.job.base import _JobConfig
 from google.cloud.bigquery.job.base import _JobReference
@@ -278,7 +279,7 @@ def null_marker(self, value):
         self._set_sub_prop("nullMarker", value)
 
     @property
-    def projection_fields(self):
+    def projection_fields(self) -> Optional[List[str]]:
         """Optional[List[str]]: If
         :attr:`google.cloud.bigquery.job.LoadJobConfig.source_format` is set to
         "DATASTORE_BACKUP", indicates which entity properties to load into

From 7c107a8a81e8312ff3389bc0efce94588ce9df98 Mon Sep 17 00:00:00 2001
From: Tim Swast <swast@google.com>
Date: Wed, 14 Jul 2021 15:24:20 -0500
Subject: [PATCH 3/3] annotate setter too

---
 google/cloud/bigquery/job/load.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/google/cloud/bigquery/job/load.py b/google/cloud/bigquery/job/load.py
index 64b5ca231..f1b045412 100644
--- a/google/cloud/bigquery/job/load.py
+++ b/google/cloud/bigquery/job/load.py
@@ -317,7 +317,7 @@ def projection_fields(self) -> Optional[List[str]]:
         return self._get_sub_prop("projectionFields")
 
     @projection_fields.setter
-    def projection_fields(self, value):
+    def projection_fields(self, value: Optional[List[str]]):
         self._set_sub_prop("projectionFields", value)
 
     @property