From 24cd190f95df1dea447ba83025a3c74ea067bfc0 Mon Sep 17 00:00:00 2001
From: Syrus Akbary <me@syrusakbary.com>
Date: Mon, 16 Nov 2015 19:48:51 -0800
Subject: [PATCH] Added support for UnionTypes
---
README.md | 2 +-
README.rst | 6 ++---
graphene/core/options.py | 2 ++
graphene/core/types/objecttype.py | 19 +++++++++++++-
graphene/core/types/tests/test_objecttype.py | 26 +++++++++++++++++++-
5 files changed, 49 insertions(+), 6 deletions(-)
diff --git a/README.md b/README.md
index e005d337..ba255c61 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ Graphene is a Python library for building GraphQL schemas/types fast and easily.
- **Django:** Automatic *Django model* mapping to Graphene Types. Check a fully working [Django](http://github.com/graphql-python/swapi-graphene) implementation
-*But, what is supported in this Python version?* **Everything**: Interfaces, ObjectTypes, Mutations and Relay (Nodes, Connections and Mutations).
+*What is supported in this Python version?* **Everything**: Interfaces, ObjectTypes, Mutations, Scalars, Unions and Relay (Nodes, Connections and Mutations).
## Installation
diff --git a/README.rst b/README.rst
index c21f2335..d0dc86a0 100644
--- a/README.rst
+++ b/README.rst
@@ -12,9 +12,9 @@ easily.
`Django <http://github.com/graphql-python/swapi-graphene>`__
implementation
-*But, what is supported in this Python version?* **Everything**:
-Interfaces, ObjectTypes, Mutations and Relay (Nodes, Connections and
-Mutations).
+*What is supported in this Python version?* **Everything**: Interfaces,
+ObjectTypes, Mutations, Scalars, Unions and Relay (Nodes, Connections
+and Mutations).
Installation
------------
diff --git a/graphene/core/options.py b/graphene/core/options.py
index 5661fedb..0e175dd0 100644
--- a/graphene/core/options.py
+++ b/graphene/core/options.py
@@ -13,8 +13,10 @@ class Options(object):
self.local_fields = []
self.is_interface = False
self.is_mutation = False
+ self.is_union = False
self.interfaces = []
self.parents = []
+ self.types = []
self.valid_attrs = DEFAULT_NAMES
def contribute_to_class(self, cls, name):
diff --git a/graphene/core/types/objecttype.py b/graphene/core/types/objecttype.py
index e2a20de4..0662199e 100644
--- a/graphene/core/types/objecttype.py
+++ b/graphene/core/types/objecttype.py
@@ -7,7 +7,7 @@ import six
from graphene import signals
from graphql.core.type import (GraphQLInputObjectType, GraphQLInterfaceType,
- GraphQLObjectType)
+ GraphQLObjectType, GraphQLUnionType)
from ..exceptions import SkipField
from ..options import Options
@@ -51,10 +51,17 @@ class ObjectTypeMeta(type):
new_class._meta.is_interface = new_class.is_interface(parents)
new_class._meta.is_mutation = new_class.is_mutation(parents)
+ union_types = [p for p in parents if issubclass(p, BaseObjectType)]
+
+ new_class._meta.is_union = len(union_types) > 1
+ new_class._meta.types = union_types
assert not (
new_class._meta.is_interface and new_class._meta.is_mutation)
+ assert not (
+ new_class._meta.is_interface and new_class._meta.is_union)
+
# Add all attributes to the class.
for obj_name, obj in attrs.items():
new_class.add_to_class(obj_name, obj)
@@ -66,6 +73,8 @@ class ObjectTypeMeta(type):
new_class.add_extra_fields()
new_fields = new_class._meta.local_fields
+ assert not(new_class._meta.is_union and new_fields), 'An union cannot have extra fields'
+
field_names = {f.name: f for f in new_fields}
for base in parents:
@@ -129,6 +138,8 @@ class BaseObjectType(BaseType):
def __new__(cls, *args, **kwargs):
if cls._meta.is_interface:
raise Exception("An interface cannot be initialized")
+ if cls._meta.is_union:
+ raise Exception("An union cannot be initialized")
return super(BaseObjectType, cls).__new__(cls)
def __init__(self, *args, **kwargs):
@@ -182,6 +193,12 @@ class BaseObjectType(BaseType):
resolve_type=partial(cls.resolve_type, schema),
fields=partial(cls.get_fields, schema)
)
+ elif cls._meta.is_union:
+ return GraphQLUnionType(
+ cls._meta.type_name,
+ types=cls._meta.types,
+ description=cls._meta.description,
+ )
return GraphQLObjectType(
cls._meta.type_name,
description=cls._meta.description,
diff --git a/graphene/core/types/tests/test_objecttype.py b/graphene/core/types/tests/test_objecttype.py
index 88532e12..6fc9cad7 100644
--- a/graphene/core/types/tests/test_objecttype.py
+++ b/graphene/core/types/tests/test_objecttype.py
@@ -4,7 +4,8 @@ from graphene.core.schema import Schema
from graphene.core.types import Int, Interface, String
from graphql.core.execution.middlewares.utils import (resolver_has_tag,
tag_resolver)
-from graphql.core.type import GraphQLInterfaceType, GraphQLObjectType
+from graphql.core.type import (GraphQLInterfaceType, GraphQLObjectType,
+ GraphQLUnionType)
class Character(Interface):
@@ -34,6 +35,16 @@ class Human(Character):
def write_prop(self, value):
self._write_prop = value
+
+class Droid(Character):
+ '''Droid description'''
+ pass
+
+
+class CharacterType(Droid, Human):
+ '''Union Type'''
+ pass
+
schema = Schema()
@@ -52,6 +63,19 @@ def test_interface_cannot_initialize():
assert 'An interface cannot be initialized' == str(excinfo.value)
+def test_union():
+ object_type = schema.T(CharacterType)
+ assert CharacterType._meta.is_union is True
+ assert isinstance(object_type, GraphQLUnionType)
+ assert object_type.description == 'Union Type'
+
+
+def test_union_cannot_initialize():
+ with raises(Exception) as excinfo:
+ CharacterType()
+ assert 'An union cannot be initialized' == str(excinfo.value)
+
+
def test_interface_resolve_type():
resolve_type = Character.resolve_type(schema, Human(object()))
assert isinstance(resolve_type, GraphQLObjectType)