First working version with relay 💪

graphene/__init__.py

@@ -1,7 +1,6 @@
 from graphql.core.type import (
     GraphQLEnumType as Enum,
     GraphQLArgument as Argument,
-    # GraphQLSchema as Schema,
     GraphQLString as String,
     GraphQLInt as Int,
     GraphQLID as ID
@@ -26,7 +25,3 @@ from graphene.core.types import (
 from graphene.decorators import (
     resolve_only_args
 )
-
-from graphene.relay import (
-    Relay
-)

graphene/core/fields.py

@@ -99,6 +99,12 @@ class Field(object):
         return '<%s>' % path
 
 
+class NativeField(Field):
+    def __init__(self, field=None):
+        super(NativeField, self).__init__(None)
+        self.field = field or getattr(self, 'field')
+
+
 class TypeField(Field):
     def __init__(self, *args, **kwargs):
         super(TypeField, self).__init__(self.field_type, *args, **kwargs)

graphene/core/options.py

@@ -54,7 +54,6 @@ class Options(object):
 
     def add_field(self, field):
         self.local_fields.append(field)
-        setattr(self.parent, field.field_name, field)
 
     @cached_property
     def fields(self):

graphene/core/types.py

@@ -91,6 +91,10 @@ class ObjectType(six.with_metaclass(ObjectTypeMeta)):
         self.instance = instance
         signals.post_init.send(self.__class__, instance=self)
 
+    def __getattr__(self, name):
+        if self.instance:
+            return getattr(self.instance, name)
+
     def get_field(self, field):
         return getattr(self.instance, field, None)
 

graphene/core/utils.py

@@ -7,18 +7,24 @@ registered_object_types = []
 
 
 def get_object_type(field_type, object_type=None):
-    _is_class = inspect.isclass(field_type)
-    if _is_class and issubclass(field_type, ObjectType):
-        field_type = field_type._meta.type
-    elif isinstance(field_type, basestring):
-        if field_type == 'self':
-            field_type = object_type._meta.type
-        else:
-            object_type = get_registered_object_type(field_type, object_type)
-            field_type = object_type._meta.type
+    native_type = get_type(field_type, object_type)
+    if native_type:
+        field_type = native_type._meta.type
     return field_type 
 
 
+def get_type(field_type, object_type=None):
+    _is_class = inspect.isclass(field_type)
+    if _is_class and issubclass(field_type, ObjectType):
+        return field_type
+    elif isinstance(field_type, basestring):
+        if field_type == 'self':
+            return object_type
+        else:
+            object_type = get_registered_object_type(field_type, object_type)
+            return object_type
+    return None
+
 def get_registered_object_type(name, object_type=None):
     app_label = None
     object_type_name = name

graphene/relay/__init__.py

@@ -1,2 +1,85 @@
-class Relay(object):
-	pass
+import collections
+
+from graphene import signals
+from graphene.core.fields import Field, NativeField
+from graphene.core.types import Interface
+from graphene.core.utils import get_type
+from graphene.utils import cached_property
+
+from graphql_relay.node.node import (
+    nodeDefinitions,
+    globalIdField,
+    fromGlobalId
+)
+from graphql_relay.connection.arrayconnection import (
+    connectionFromArray
+)
+from graphql_relay.connection.connection import (
+    connectionArgs,
+    connectionDefinitions
+)
+
+registered_nodes = {}
+
+
+def getNode(globalId, *args):
+    resolvedGlobalId = fromGlobalId(globalId)
+    _type, _id = resolvedGlobalId.type, resolvedGlobalId.id
+    if _type in registered_nodes:
+        object_type = registered_nodes[_type]
+        return object_type.get_node(_id)
+
+
+def getNodeType(obj):
+    return obj._meta.type
+
+
+_nodeDefinitions = nodeDefinitions(getNode, getNodeType)
+
+
+class Node(Interface):
+    @classmethod
+    def get_graphql_type(cls):
+        if cls is Node:
+            # Return only nodeInterface when is the Node Inerface
+            return _nodeDefinitions.nodeInterface
+        return super(Node, cls).get_graphql_type()
+
+
+class NodeField(NativeField):
+    field = _nodeDefinitions.nodeField
+
+
+class ConnectionField(Field):
+    def __init__(self, field_type, resolve=None, description=''):
+        super(ConnectionField, self).__init__(field_type, resolve=resolve, 
+                                              args=connectionArgs, description=description)
+
+    def resolve(self, instance, args, info):
+        resolved = super(ConnectionField, self).resolve(instance, args, info)
+        if resolved:
+            assert isinstance(resolved, collections.Iterable), 'Resolved value from the connection field have to be iterable'
+            return connectionFromArray(resolved, args)
+
+    @cached_property
+    def type(self):
+        object_type = get_type(self.field_type, self.object_type)
+        assert issubclass(object_type, Node), 'Only nodes have connections.'
+        return object_type.connection
+
+
+@signals.class_prepared.connect
+def object_type_created(object_type):
+    if issubclass(object_type, Node):
+        type_name = object_type._meta.type_name
+        assert type_name not in registered_nodes, 'Two nodes with the same type_name: %s' % type_name
+        registered_nodes[type_name] = object_type
+        # def getId(*args, **kwargs):
+        #     print '**GET ID', args, kwargs
+        #     return 2
+        field = NativeField(globalIdField(type_name))
+        object_type.add_to_class('id', field)
+        assert hasattr(object_type, 'get_node'), 'get_node classmethod not found in %s Node' % type_name
+
+        connection = connectionDefinitions(type_name, object_type._meta.type).connectionType
+        object_type.add_to_class('connection', connection)

tests/core/test_types.py

@@ -29,7 +29,7 @@ def test_interface():
     assert Character._meta.type_name == 'Character'
     assert isinstance(object_type, GraphQLInterfaceType)
     assert object_type.description == 'Character description'
-    assert object_type.get_fields() == {'name': Character.name.field}
+    assert object_type.get_fields() == {'name': Character._meta.fields_map['name'].field}
 
 def test_object_type():
     object_type = Human._meta.type
@@ -37,5 +37,5 @@ def test_object_type():
     assert Human._meta.type_name == 'Human'
     assert isinstance(object_type, GraphQLObjectType)
     assert object_type.description == 'Human description'
-    assert object_type.get_fields() == {'name': Character.name.field, 'friends': Human.friends.field}
+    assert object_type.get_fields() == {'name': Character._meta.fields_map['name'].field, 'friends': Human._meta.fields_map['friends'].field}
     assert object_type.get_interfaces() == [Character._meta.type]

tests/starwars_relay/data.py

@@ -0,0 +1,98 @@
+from collections import namedtuple
+
+Ship = namedtuple('Ship',['id', 'name'])
+Faction = namedtuple('Faction',['id', 'name', 'ships'])
+
+xwing = Ship(
+    id='1',
+    name='X-Wing',
+)
+
+ywing = Ship(
+    id='2',
+    name='Y-Wing',
+)
+
+awing = Ship(
+    id='3',
+    name='A-Wing',
+)
+
+# Yeah, technically it's Corellian. But it flew in the service of the rebels,
+# so for the purposes of this demo it's a rebel ship.
+falcon = Ship(
+    id='4',
+    name='Millenium Falcon',
+)
+
+homeOne = Ship(
+    id='5',
+    name='Home One',
+)
+
+tieFighter = Ship(
+    id='6',
+    name='TIE Fighter',
+)
+
+tieInterceptor = Ship(
+    id='7',
+    name='TIE Interceptor',
+)
+
+executor = Ship(
+    id='8',
+    name='Executor',
+)
+
+rebels = Faction(
+    id='1',
+    name='Alliance to Restore the Republic',
+    ships=['1', '2', '3', '4', '5']
+)
+
+empire = Faction(
+    id='2',
+    name='Galactic Empire',
+    ships= ['6', '7', '8']
+)
+
+data = {
+    'Faction': {
+        '1': rebels,
+        '2': empire
+    },
+    'Ship': {
+        '1': xwing,
+        '2': ywing,
+        '3': awing,
+        '4': falcon,
+        '5': homeOne,
+        '6': tieFighter,
+        '7': tieInterceptor,
+        '8': executor
+    }
+}
+
+def createShip(shipName, factionId):
+    nextShip = len(data['Ship'].keys())+1
+    newShip = Ship(
+        id=str(nextShip),
+        name=shipName
+    )
+    data['Ship'][newShip.id] = newShip
+    data['Faction'][factionId].ships.append(newShip.id)
+    return newShip
+
+
+def getShip(_id):
+    return data['Ship'][_id]
+
+def getFaction(_id):
+    return data['Faction'][_id]
+
+def getRebels():
+    return rebels
+
+def getEmpire():
+    return empire

tests/starwars_relay/schema.py

@@ -2,60 +2,52 @@ import graphene
 from graphene import resolve_only_args, relay
 
 from .data import (
-    getHero, getHuman, getCharacter, getDroid,
-    Human as _Human, Droid as _Droid)
-
-Episode = graphene.Enum('Episode', dict(
-    NEWHOPE=4,
-    EMPIRE=5,
-    JEDI=6
-))
+    getFaction,
+    getShip,
+    getRebels,
+    getEmpire,
+)
 
 
-def wrap_character(character):
-    if isinstance(character, _Human):
-        return Human(character)
-    elif isinstance(character, _Droid):
-        return Droid(character)
+class Ship(relay.Node):
+    '''A ship in the Star Wars saga'''
+    name = graphene.StringField(description='The name of the ship.')
+
+    @classmethod
+    def get_node(cls, id):
+        ship = getShip(id)
+        if ship:
+            return Ship(ship)
 
 
-class Character(graphene.Interface):
-    name = graphene.StringField()
-    friends = relay.Connection('Character')
-    appearsIn = graphene.ListField(Episode)
+class Faction(relay.Node):
+    '''A faction in the Star Wars saga'''
+    name = graphene.StringField(description='The name of the faction.')
+    ships = relay.ConnectionField(Ship, description='The ships used by the faction.')
 
-    def resolve_friends(self, args, *_):
-        return [wrap_character(getCharacter(f)) for f in self.instance.friends]
+    @resolve_only_args
+    def resolve_ships(self, **kwargs):
+        return [Ship(getShip(ship)) for ship in self.instance.ships]
 
-
-class Human(relay.Node, Character):
-    homePlanet = graphene.StringField()
-
-
-class Droid(relay.Node, Character):
-    primaryFunction = graphene.StringField()
+    @classmethod
+    def get_node(cls, id):
+        faction = getFaction(id)
+        if faction:
+            return Faction(faction)
 
 
 class Query(graphene.ObjectType):
-    hero = graphene.Field(Character,
-                          episode=graphene.Argument(Episode))
-    human = graphene.Field(Human,
-                           id=graphene.Argument(graphene.String))
-    droid = graphene.Field(Droid,
-                           id=graphene.Argument(graphene.String))
-    node = graphene.Field(relay.Node)
+    rebels = graphene.Field(Faction)
+    empire = graphene.Field(Faction)
+    node = relay.NodeField()
 
     @resolve_only_args
-    def resolve_hero(self, episode):
-        return wrap_character(getHero(episode))
+    def resolve_rebels(self):
+        return Faction(getRebels())
 
     @resolve_only_args
-    def resolve_human(self, id):
-        return wrap_character(getHuman(id))
-
-    @resolve_only_args
-    def resolve_droid(self, id):
-        return wrap_character(getDroid(id))
+    def resolve_empire(self):
+        return Faction(getEmpire())
 
 
 Schema = graphene.Schema(query=Query)

tests/starwars_relay/schema_other.py

@@ -0,0 +1,60 @@
+import graphene
+from graphene import resolve_only_args, relay
+
+from .data import (
+    getHero, getHuman, getCharacter, getDroid,
+    Human as _Human, Droid as _Droid)
+
+Episode = graphene.Enum('Episode', dict(
+    NEWHOPE=4,
+    EMPIRE=5,
+    JEDI=6
+))
+
+def wrap_character(character):
+    if isinstance(character, _Human):
+        return Human(character)
+    elif isinstance(character, _Droid):
+        return Droid(character)
+
+
+class Character(graphene.Interface):
+    name = graphene.StringField()
+    friends = relay.Connection('Character')
+    appearsIn = graphene.ListField(Episode)
+
+    def resolve_friends(self, args, *_):
+        return [wrap_character(getCharacter(f)) for f in self.instance.friends]
+
+
+class Human(relay.Node, Character):
+    homePlanet = graphene.StringField()
+
+
+class Droid(relay.Node, Character):
+    primaryFunction = graphene.StringField()
+
+
+class Query(graphene.ObjectType):
+    hero = graphene.Field(Character,
+                          episode=graphene.Argument(Episode))
+    human = graphene.Field(Human,
+                           id=graphene.Argument(graphene.String))
+    droid = graphene.Field(Droid,
+                           id=graphene.Argument(graphene.String))
+    node = relay.NodeField()
+
+    @resolve_only_args
+    def resolve_hero(self, episode):
+        return wrap_character(getHero(episode))
+
+    @resolve_only_args
+    def resolve_human(self, id):
+        return wrap_character(getHuman(id))
+
+    @resolve_only_args
+    def resolve_droid(self, id):
+        return wrap_character(getDroid(id))
+
+
+Schema = graphene.Schema(query=Query)

tests/starwars_relay/test_connections.py

@@ -0,0 +1,37 @@
+from pytest import raises
+from graphql.core import graphql
+
+from .schema import Schema
+
+def test_correct_fetch_first_ship_rebels():
+    query = '''
+    query RebelsShipsQuery {
+      rebels {
+        name,
+        ships(first: 1) {
+          edges {
+            node {
+              name
+            }
+          }
+        }
+      }
+    }
+    '''
+    expected = {
+      'rebels': {
+        'name': 'Alliance to Restore the Republic',
+        'ships': {
+          'edges': [
+            {
+              'node': {
+                'name': 'X-Wing'
+              }
+            }
+          ]
+        }
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected

tests/starwars_relay/test_objectidentification.py

@@ -0,0 +1,105 @@
+from pytest import raises
+from graphql.core import graphql
+
+from .schema import Schema
+
+def test_correctly_fetches_id_name_rebels():
+    query = '''
+      query RebelsQuery {
+        rebels {
+          id
+          name
+        }
+      }
+    '''
+    expected = {
+      'rebels': {
+        'id': 'RmFjdGlvbjox',
+        'name': 'Alliance to Restore the Republic'
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected
+
+def test_correctly_refetches_rebels():
+    query = '''
+      query RebelsRefetchQuery {
+        node(id: "RmFjdGlvbjox") {
+          id
+          ... on Faction {
+            name
+          }
+        }
+      }
+    '''
+    expected = {
+      'node': {
+        'id': 'RmFjdGlvbjox',
+        'name': 'Alliance to Restore the Republic'
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected
+
+def test_correctly_fetches_id_name_empire():
+    query = '''
+      query EmpireQuery {
+        empire {
+          id
+          name
+        }
+      }
+    '''
+    expected = {
+      'empire': {
+        'id': 'RmFjdGlvbjoy',
+        'name': 'Galactic Empire'
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected
+
+def test_correctly_refetches_empire():
+    query = '''
+      query EmpireRefetchQuery {
+        node(id: "RmFjdGlvbjoy") {
+          id
+          ... on Faction {
+            name
+          }
+        }
+      }
+    '''
+    expected = {
+      'node': {
+        'id': 'RmFjdGlvbjoy',
+        'name': 'Galactic Empire'
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected
+
+def test_correctly_refetches_xwing():
+    query = '''
+      query XWingRefetchQuery {
+        node(id: "U2hpcDox") {
+          id
+          ... on Ship {
+            name
+          }
+        }
+      }
+    '''
+    expected = {
+      'node': {
+        'id': 'U2hpcDox',
+        'name': 'X-Wing'
+      }
+    }
+    result = Schema.execute(query)
+    assert result.errors == None
+    assert result.data == expected