Added batch support

Author: syrusakbary

Diff for: README.md

@@ -13,6 +13,8 @@ from flask_graphql import GraphQLView
 
 app.add_url_rule('/graphql', view_func=GraphQLView.as_view('graphql', schema=schema, graphiql=True))
 
+# Optional, for adding batch query support (used in Apollo-Client)
+app.add_url_rule('/graphql/batch', view_func=GraphQLView.as_view('graphql', schema=schema, batch=True))
 ```
 
 This will add `/graphql` and `/graphiql` endpoints to your app.

Diff for: flask_graphql/graphqlview.py

@@ -32,6 +32,7 @@ class GraphQLView(View):
     graphiql_version = None
     graphiql_template = None
     middleware = None
+    batch = False
 
     methods = ['GET', 'POST', 'PUT', 'DELETE']
 
@@ -41,6 +42,7 @@ def __init__(self, **kwargs):
             if hasattr(self, key):
                 setattr(self, key, value)
 
+        assert not all((self.graphiql, self.batch)), 'Use either graphiql or batch processing'
         assert isinstance(self.schema, GraphQLSchema), 'A Schema is required to be provided to GraphQLView.'
 
     # noinspection PyUnusedLocal
@@ -66,33 +68,15 @@ def dispatch_request(self):
             data = self.parse_body(request)
             show_graphiql = self.graphiql and self.can_display_graphiql(data)
 
-            query, variables, operation_name = self.get_graphql_params(request, data)
-
-            execution_result = self.execute_graphql_request(
-                data,
-                query,
-                variables,
-                operation_name,
-                show_graphiql
-            )
-
-            if execution_result:
-                response = {}
-
-                if execution_result.errors:
-                    response['errors'] = [self.format_error(e) for e in execution_result.errors]
-
-                if execution_result.invalid:
-                    status_code = 400
-                else:
-                    status_code = 200
-                    response['data'] = execution_result.data
-
-                result = self.json_encode(request, response)
+            if self.batch:
+                responses = [self.get_response(request, entry) for entry in data]
+                result = '[{}]'.format(','.join([response[0] for response in responses]))
+                status_code = max(responses, key=lambda response: response[1])[1]
             else:
-                result = None
+                result, status_code = self.get_response(request, data, show_graphiql)
 
             if show_graphiql:
+                query, variables, operation_name, id = self.get_graphql_params(request, data)
                 return render_graphiql(
                     graphiql_version=self.graphiql_version,
                     graphiql_template=self.graphiql_template,
@@ -118,6 +102,43 @@ def dispatch_request(self):
                 content_type='application/json'
             )
 
+    def get_response(self, request, data, show_graphiql=False):
+        query, variables, operation_name, id = self.get_graphql_params(request, data)
+
+        execution_result = self.execute_graphql_request(
+            data,
+            query,
+            variables,
+            operation_name,
+            show_graphiql
+        )
+
+        status_code = 200
+        if execution_result:
+            response = {}
+
+            if execution_result.errors:
+                response['errors'] = [self.format_error(e) for e in execution_result.errors]
+
+            if execution_result.invalid:
+                status_code = 400
+            else:
+                status_code = 200
+                response['data'] = execution_result.data
+
+            if self.batch:
+                response = {
+                    'id': id,
+                    'payload': response,
+                    'status': status_code,
+                }
+
+            result = self.json_encode(request, response)
+        else:
+            result = None
+
+        return result, status_code
+
     def json_encode(self, request, d):
         if not self.pretty and not request.args.get('pretty'):
             return json.dumps(d, separators=(',', ':'))
@@ -134,7 +155,10 @@ def parse_body(self, request):
         elif content_type == 'application/json':
             try:
                 request_json = json.loads(request.data.decode('utf8'))
-                assert isinstance(request_json, dict)
+                if self.batch:
+                    assert isinstance(request_json, list)
+                else:
+                    assert isinstance(request_json, dict)
                 return request_json
             except:
                 raise HttpError(BadRequest('POST body sent invalid JSON.'))
@@ -207,6 +231,7 @@ def request_wants_html(cls, request):
     def get_graphql_params(request, data):
         query = request.args.get('query') or data.get('query')
         variables = request.args.get('variables') or data.get('variables')
+        id = request.args.get('id') or data.get('id')
 
         if variables and isinstance(variables, six.text_type):
             try:
@@ -216,7 +241,7 @@ def get_graphql_params(request, data):
 
         operation_name = request.args.get('operationName') or data.get('operationName')
 
-        return query, variables, operation_name
+        return query, variables, operation_name, id
 
     @staticmethod
     def format_error(error):

Diff for: tests/app.py

@@ -3,10 +3,10 @@
 from .schema import Schema
 
 
-def create_app(**kwargs):
+def create_app(path='/graphql', **kwargs):
     app = Flask(__name__)
     app.debug = True
-    app.add_url_rule('/graphql', view_func=GraphQLView.as_view('graphql', schema=Schema, **kwargs))
+    app.add_url_rule(path, view_func=GraphQLView.as_view('graphql', schema=Schema, **kwargs))
     return app
 
 

Diff for: tests/test_graphqlview.py

@@ -33,6 +33,8 @@ def response_json(response):
 
 
 j = lambda **kwargs: json.dumps(kwargs)
+jl = lambda **kwargs: json.dumps([kwargs])
+
 
 def test_allows_get_with_query_param(client):
     response = client.get(url_string(query='{test}'))
@@ -453,3 +455,71 @@ def test_post_multipart_data(client):
 
     assert response.status_code == 200
     assert response_json(response) == {'data': {u'writeTest': {u'test': u'Hello World'}}}
+
+
+@pytest.mark.parametrize('app', [create_app(batch=True)])
+def test_batch_allows_post_with_json_encoding(client):
+    response = client.post(
+        url_string(),
+        data=jl(id=1, query='{test}'),
+        content_type='application/json'
+    )
+
+    assert response.status_code == 200
+    assert response_json(response) == [{
+        'id': 1,
+        'payload': { 'data': {'test': "Hello World"} },
+        'status': 200,
+    }]
+
+
+@pytest.mark.parametrize('app', [create_app(batch=True)])
+def test_batch_supports_post_json_query_with_json_variables(client):
+    response = client.post(
+        url_string(),
+        data=jl(
+            id=1,
+            query='query helloWho($who: String){ test(who: $who) }',
+            variables={'who': "Dolly"}
+        ),
+        content_type='application/json'
+    )
+
+    assert response.status_code == 200
+    assert response_json(response) == [{
+        'id': 1,
+        'payload': { 'data': {'test': "Hello Dolly"} },
+        'status': 200,
+    }]
+ 
+          
+@pytest.mark.parametrize('app', [create_app(batch=True)])
+def test_batch_allows_post_with_operation_name(client):
+    response = client.post(
+        url_string(),
+        data=jl(
+            id=1,
+            query='''
+            query helloYou { test(who: "You"), ...shared }
+            query helloWorld { test(who: "World"), ...shared }
+            query helloDolly { test(who: "Dolly"), ...shared }
+            fragment shared on QueryRoot {
+              shared: test(who: "Everyone")
+            }
+            ''',
+            operationName='helloWorld'
+        ),
+        content_type='application/json'
+    )
+
+    assert response.status_code == 200
+    assert response_json(response) == [{
+        'id': 1,
+        'payload': {
+            'data': {
+                'test': 'Hello World',
+                'shared': 'Hello Everyone'
+            }
+        },
+        'status': 200,
+    }]