BigQuery: add reference property to Table and Dataset

This makes it easier to call `get_table`, `get_dataset`, or other
functions that want just a reference, not a full resource.

Author: tswast

bigquery/google/cloud/bigquery/dataset.py

@@ -279,6 +279,17 @@ def full_dataset_id(self):
         """
         return self._properties.get('id')
 
+    @property
+    def reference(self):
+        """A :class:`~google.cloud.bigquery.dataset.DatasetReference` pointing to
+        this dataset.
+
+        Returns:
+            google.cloud.bigquery.dataset.DatasetReference:
+                A pointer to this dataset
+        """
+        return DatasetReference(self.project, self.dataset_id)
+
     @property
     def etag(self):
         """ETag for the dataset resource.

bigquery/google/cloud/bigquery/table.py

@@ -204,6 +204,20 @@ def table_id(self):
         """
         return self._table_id
 
+    @property
+    def reference(self):
+        """A :class:`~google.cloud.bigquery.table.TableReference` pointing to
+        this table.
+
+        Returns:
+            google.cloud.bigquery.table.TableReference:
+                A pointer to this table
+        """
+        from google.cloud.bigquery import dataset
+
+        dataset_ref = dataset.DatasetReference(self.project, self.dataset_id)
+        return TableReference(dataset_ref, self.table_id)
+
     @property
     def path(self):
         """URL path for the table's APIs.

bigquery/tests/unit/test_dataset.py

@@ -245,7 +245,10 @@ def _verify_access_entry(self, access_entries, resource):
 
     def _verify_readonly_resource_properties(self, dataset, resource):
 
+        self.assertEqual(dataset.project, self.PROJECT)
         self.assertEqual(dataset.dataset_id, self.DS_ID)
+        self.assertEqual(dataset.reference.project, self.PROJECT)
+        self.assertEqual(dataset.reference.dataset_id, self.DS_ID)
 
         if 'creationTime' in resource:
             self.assertEqual(dataset.created, self.WHEN)

bigquery/tests/unit/test_table.py

@@ -293,6 +293,9 @@ def test_ctor(self):
         self.assertEqual(table.table_id, self.TABLE_NAME)
         self.assertEqual(table.project, self.PROJECT)
         self.assertEqual(table.dataset_id, self.DS_ID)
+        self.assertEqual(table.reference.table_id, self.TABLE_NAME)
+        self.assertEqual(table.reference.project, self.PROJECT)
+        self.assertEqual(table.reference.dataset_id, self.DS_ID)
         self.assertEqual(
             table.path,
             '/projects/%s/datasets/%s/tables/%s' % (