Refactor 'Document.get' to use the 'GetDocument' API. (#6534)

Update conformance test to actually run for 'get'.

Toward #6533.

firestore/google/cloud/firestore_v1beta1/document.py

@@ -18,7 +18,9 @@
 
 import six
 
+from google.api_core import exceptions
 from google.cloud.firestore_v1beta1 import _helpers
+from google.cloud.firestore_v1beta1.proto import common_pb2
 from google.cloud.firestore_v1beta1.watch import Watch
 
 
@@ -423,9 +425,37 @@ def get(self, field_paths=None, transaction=None):
         if isinstance(field_paths, six.string_types):
             raise ValueError(
                 "'field_paths' must be a sequence of paths, not a string.")
-        snapshot_generator = self._client.get_all(
-            [self], field_paths=field_paths, transaction=transaction)
-        return _consume_single_get(snapshot_generator)
+
+        if field_paths is not None:
+            mask = common_pb2.DocumentMask(field_paths=sorted(field_paths))
+        else:
+            mask = None
+
+        firestore_api = self._client._firestore_api
+        try:
+            document_pb = firestore_api.get_document(
+                self._document_path,
+                mask=mask,
+                transaction=_helpers.get_transaction_id(transaction),
+                metadata=self._client._rpc_metadata)
+        except exceptions.NotFound:
+            data = None
+            exists = False
+            create_time = None
+            update_time = None
+        else:
+            data = _helpers.decode_dict(document_pb.fields, self._client)
+            exists = True
+            create_time = document_pb.create_time
+            update_time = document_pb.update_time
+
+        return DocumentSnapshot(
+            reference=self,
+            data=data,
+            exists=exists,
+            read_time=None,  # No server read_time available
+            create_time=create_time,
+            update_time=update_time)
 
     def collections(self, page_size=None):
         """List subcollections of the current document.

firestore/tests/system.py

@@ -413,7 +413,6 @@ def test_document_get(client, cleanup):
     write_result = document.create(data)
     snapshot = document.get()
     check_snapshot(snapshot, document, data, write_result)
-    assert_timestamp_less(snapshot.create_time, snapshot.read_time)
 
 
 def test_document_delete(client, cleanup):

firestore/tests/unit/test_cross_language.py

@@ -21,6 +21,7 @@
 import pytest
 
 from google.protobuf import text_format
+from google.cloud.firestore_v1beta1.proto import document_pb2
 from google.cloud.firestore_v1beta1.proto import firestore_pb2
 from google.cloud.firestore_v1beta1.proto import test_pb2
 from google.cloud.firestore_v1beta1.proto import write_pb2
@@ -170,19 +171,18 @@ def test_create_testprotos(test_proto):
 @pytest.mark.parametrize('test_proto', _GET_TESTPROTOS)
 def test_get_testprotos(test_proto):
     testcase = test_proto.get
-    # XXX this stub currently does nothing because no get testcases have
-    # is_error; taking this bit out causes the existing tests to fail
-    # due to a lack of batch getting
-    try:
-        testcase.is_error
-    except AttributeError:
-        return
-    else:  # pragma: NO COVER
-        testcase = test_proto.get
-        firestore_api = _mock_firestore_api()
-        client, document = _make_client_document(firestore_api, testcase)
-        call = functools.partial(document.get, None, None)
-        _run_testcase(testcase, call, firestore_api, client)
+    firestore_api = mock.Mock(spec=['get_document'])
+    response = document_pb2.Document()
+    firestore_api.get_document.return_value = response
+    client, document = _make_client_document(firestore_api, testcase)
+
+    document.get()  # No '.textprotos' for errors, field_paths.
+
+    firestore_api.get_document.assert_called_once_with(
+        document._document_path,
+        mask=None,
+        transaction=None,
+        metadata=client._rpc_metadata)
 
 
 @pytest.mark.parametrize('test_proto', _SET_TESTPROTOS)

firestore/tests/unit/test_document.py

@@ -463,74 +463,90 @@ def test_delete_with_option(self):
         )
         self._delete_helper(last_update_time=timestamp_pb)
 
-    def test_get_w_single_field_path(self):
-        client = mock.Mock(spec=[])
+    def _get_helper(
+            self, field_paths=None, use_transaction=False, not_found=False):
+        from google.api_core.exceptions import NotFound
+        from google.cloud.firestore_v1beta1.proto import common_pb2
+        from google.cloud.firestore_v1beta1.proto import document_pb2
+        from google.cloud.firestore_v1beta1.transaction import Transaction
 
-        document = self._make_one('yellow', 'mellow', client=client)
-        with self.assertRaises(ValueError):
-            document.get('foo')
+        # Create a minimal fake GAPIC with a dummy response.
+        create_time = 123
+        update_time = 234
+        firestore_api = mock.Mock(spec=['get_document'])
+        response = mock.create_autospec(document_pb2.Document)
+        response.fields = {}
+        response.create_time = create_time
+        response.update_time = update_time
+
+        if not_found:
+            firestore_api.get_document.side_effect = NotFound('testing')
+        else:
+            firestore_api.get_document.return_value = response
 
-    def test_get_success(self):
-        # Create a minimal fake client with a dummy response.
-        response_iterator = iter([mock.sentinel.snapshot])
-        client = mock.Mock(spec=['get_all'])
-        client.get_all.return_value = response_iterator
+        client = _make_client('donut-base')
+        client._firestore_api_internal = firestore_api
 
-        # Actually make a document and call get().
-        document = self._make_one('yellow', 'mellow', client=client)
-        snapshot = document.get()
+        document = self._make_one('where', 'we-are', client=client)
 
-        # Verify the response and the mocks.
-        self.assertIs(snapshot, mock.sentinel.snapshot)
-        client.get_all.assert_called_once_with(
-            [document], field_paths=None, transaction=None)
+        if use_transaction:
+            transaction = Transaction(client)
+            transaction_id = transaction._id = b'asking-me-2'
+        else:
+            transaction = None
+
+        snapshot = document.get(
+            field_paths=field_paths, transaction=transaction)
+
+        self.assertIs(snapshot.reference, document)
+        if not_found:
+            self.assertIsNone(snapshot._data)
+            self.assertFalse(snapshot.exists)
+            self.assertIsNone(snapshot.read_time)
+            self.assertIsNone(snapshot.create_time)
+            self.assertIsNone(snapshot.update_time)
+        else:
+            self.assertEqual(snapshot.to_dict(), {})
+            self.assertTrue(snapshot.exists)
+            self.assertIsNone(snapshot.read_time)
+            self.assertIs(snapshot.create_time, create_time)
+            self.assertIs(snapshot.update_time, update_time)
+
+        # Verify the request made to the API
+        if field_paths is not None:
+            mask = common_pb2.DocumentMask(field_paths=sorted(field_paths))
+        else:
+            mask = None
 
-    def test_get_with_transaction(self):
-        from google.cloud.firestore_v1beta1.client import Client
-        from google.cloud.firestore_v1beta1.transaction import Transaction
+        if use_transaction:
+            expected_transaction_id = transaction_id
+        else:
+            expected_transaction_id = None
 
-        # Create a minimal fake client with a dummy response.
-        response_iterator = iter([mock.sentinel.snapshot])
-        client = mock.create_autospec(Client, instance=True)
-        client.get_all.return_value = response_iterator
+        firestore_api.get_document.assert_called_once_with(
+            document._document_path,
+            mask=mask,
+            transaction=expected_transaction_id,
+            metadata=client._rpc_metadata)
 
-        # Actually make a document and call get().
-        document = self._make_one('yellow', 'mellow', client=client)
-        transaction = Transaction(client)
-        transaction._id = b'asking-me-2'
-        snapshot = document.get(transaction=transaction)
+    def test_get_not_found(self):
+        self._get_helper(not_found=True)
 
-        # Verify the response and the mocks.
-        self.assertIs(snapshot, mock.sentinel.snapshot)
-        client.get_all.assert_called_once_with(
-            [document], field_paths=None, transaction=transaction)
+    def test_get_default(self):
+        self._get_helper()
 
-    def test_get_not_found(self):
-        from google.cloud.firestore_v1beta1.document import DocumentSnapshot
+    def test_get_w_string_field_path(self):
+        with self.assertRaises(ValueError):
+            self._get_helper(field_paths='foo')
 
-        # Create a minimal fake client with a dummy response.
-        read_time = 123
-        expected = DocumentSnapshot(None, None, False, read_time, None, None)
-        response_iterator = iter([expected])
-        client = mock.Mock(
-            _database_string='sprinklez',
-            spec=['_database_string', 'get_all'])
-        client.get_all.return_value = response_iterator
-
-        # Actually make a document and call get().
-        document = self._make_one('house', 'cowse', client=client)
-        field_paths = ['x.y', 'x.z', 't']
-        snapshot = document.get(field_paths=field_paths)
-        self.assertIsNone(snapshot.reference)
-        self.assertIsNone(snapshot._data)
-        self.assertFalse(snapshot.exists)
-        self.assertEqual(snapshot.read_time, expected.read_time)
-        self.assertIsNone(snapshot.create_time)
-        self.assertIsNone(snapshot.update_time)
+    def test_get_with_field_path(self):
+        self._get_helper(field_paths=['foo'])
 
-        # Verify the response and the mocks.
-        client.get_all.assert_called_once_with(
-            [document], field_paths=field_paths, transaction=None)
+    def test_get_with_multiple_field_paths(self):
+        self._get_helper(field_paths=['foo', 'bar.baz'])
+
+    def test_get_with_transaction(self):
+        self._get_helper(use_transaction=True)
 
     def _collections_helper(self, page_size=None):
         from google.api_core.page_iterator import Iterator