Feature/allow errors to be raised or returned

gql/client.py

@@ -7,6 +7,7 @@
 
 log = logging.getLogger(__name__)
 
+
 class RetryError(Exception):
     """Custom exception thrown when retry logic fails"""
     def __init__(self, retries_count, last_exception):
@@ -15,9 +16,15 @@ def __init__(self, retries_count, last_exception):
         self.last_exception = last_exception
 
 
+class ResultError(Exception):
+    """Custom exception thrown when results contain an errors."""
+    def __init__(self, message):
+        super(Exception, self).__init__(message)
+
+
 class Client(object):
     def __init__(self, schema=None, introspection=None, type_def=None, transport=None,
-                 fetch_schema_from_transport=False, retries=0):
+                 fetch_schema_from_transport=False, retries=0, raise_error=False):
         assert not(type_def and introspection), 'Cant provide introspection type definition at the same time'
         if transport and fetch_schema_from_transport:
             assert not schema, 'Cant fetch the schema from transport if is already provided'
@@ -36,6 +43,7 @@ def __init__(self, schema=None, introspection=None, type_def=None, transport=Non
         self.introspection = introspection
         self.transport = transport
         self.retries = retries
+        self.raise_error = raise_error
 
     def validate(self, document):
         if not self.schema:
@@ -50,7 +58,10 @@ def execute(self, document, *args, **kwargs):
 
         result = self._get_result(document, *args, **kwargs)
         if result.errors:
-            raise Exception(str(result.errors[0]))
+            if self.raise_error:
+                return result
+            else:
+                raise ResultError(str(result.errors[0]))
 
         return result.data
 

tests/conftest.py

@@ -0,0 +1,16 @@
+import pytest
+
+from gql import gql
+
+
+@pytest.fixture()
+def gql_query():
+    return gql('''
+    {
+      myFavoriteFilm: film(id:"RmlsbToz") {
+        id
+        title
+        episodeId
+      }
+    }
+    ''')

tests/test_client.py

@@ -2,33 +2,67 @@
 import mock
 
 from gql import Client, gql
+from gql.client import ResultError
 from gql.transport.requests import RequestsHTTPTransport
 
 
 @mock.patch('gql.transport.requests.RequestsHTTPTransport.execute')
-def test_retries(execute_mock):
+def test_retries(execute_mock, gql_query):
     expected_retries = 3
-    execute_mock.side_effect =Exception("fail")
+    execute_mock.side_effect = Exception("fail")
 
     client = Client(
         retries=expected_retries,
         transport=RequestsHTTPTransport(url='http://swapi.graphene-python.org/graphql')
     )
 
-    query = gql('''
-    {
-      myFavoriteFilm: film(id:"RmlsbToz") {
-        id
-        title
-        episodeId
-      }
-    }
-    ''')
-
     with pytest.raises(Exception):
-        client.execute(query)
+        client.execute(gql_query)
 
     assert execute_mock.call_count == expected_retries
 
 
+@mock.patch('gql.transport.requests.RequestsHTTPTransport.execute')
+def test_client_does_not_raise_exception(execute_mock, gql_query):
+    mock_response = mock.Mock()
+    mock_response.errors = None
+    execute_mock.return_value = mock_response
+
+    client = Client(
+        transport=RequestsHTTPTransport(url='http://swapi.graphene-python.org/graphql'),
+        raise_error=False
+    )
+
+    assert client.execute(gql_query)
+
+
+@mock.patch('gql.transport.requests.RequestsHTTPTransport.execute')
+def test_client_raises_error_exception(execute_mock, gql_query):
+
+    mock_response = mock.Mock()
+    mock_response.errors = [{'message': 'a real error'}]
+    execute_mock.return_value = mock_response
+
+    client = Client(
+        transport=RequestsHTTPTransport(url='http://swapi.graphene-python.org/graphql'),
+        raise_error=False
+    )
+
+    with pytest.raises(ResultError):
+        client.execute(gql_query)
+
+
+@mock.patch('gql.transport.requests.RequestsHTTPTransport.execute')
+def test_client_returns_errors(execute_mock, gql_query):
+
+    mock_response = mock.Mock()
+    mock_response.errors = [{'message': 'a real error'}]
+    execute_mock.return_value = mock_response
+
+    client = Client(
+        transport=RequestsHTTPTransport(url='http://swapi.graphene-python.org/graphql'),
+        raise_error=True
+    )
 
+    response = client.execute(gql_query)
+    assert response.errors == mock_response.errors