Added Enum type

examples/starwars/data.py

@@ -9,7 +9,7 @@ def setup():
         id='1000',
         name='Luke Skywalker',
         friends=['1002', '1003', '2000', '2001'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         home_planet='Tatooine',
     )
 
@@ -17,7 +17,7 @@ def setup():
         id='1001',
         name='Darth Vader',
         friends=['1004'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         home_planet='Tatooine',
     )
 
@@ -25,7 +25,7 @@ def setup():
         id='1002',
         name='Han Solo',
         friends=['1000', '1003', '2001'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         home_planet=None,
     )
 
@@ -33,7 +33,7 @@ def setup():
         id='1003',
         name='Leia Organa',
         friends=['1000', '1002', '2000', '2001'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         home_planet='Alderaan',
     )
 
@@ -41,7 +41,7 @@ def setup():
         id='1004',
         name='Wilhuff Tarkin',
         friends=['1001'],
-        # appears_in=[4],
+        appears_in=[4],
         home_planet=None,
     )
 
@@ -57,7 +57,7 @@ def setup():
         id='2000',
         name='C-3PO',
         friends=['1000', '1002', '1003', '2001'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         primary_function='Protocol',
     )
 
@@ -65,7 +65,7 @@ def setup():
         id='2001',
         name='R2-D2',
         friends=['1000', '1002', '1003'],
-        # appears_in=[4, 5, 6],
+        appears_in=[4, 5, 6],
         primary_function='Astromech',
     )
 

examples/starwars/schema.py

@@ -4,17 +4,17 @@ from graphene import resolve_only_args
 from .data import get_character, get_droid, get_hero, get_human
 
 
-# class Episode(graphene.Enum):
-#     NEWHOPE = 4
-#     EMPIRE = 5
-#     JEDI = 6
+class Episode(graphene.Enum):
+    NEWHOPE = 4
+    EMPIRE = 5
+    JEDI = 6
 
 
 class Character(graphene.Interface):
     id = graphene.ID()
     name = graphene.String()
     friends = graphene.List(lambda: Character)
-    # appears_in = graphene.List(Episode)
+    appears_in = graphene.List(Episode)
 
 
 @graphene.implements(Character)
@@ -37,7 +37,7 @@ class Droid(graphene.ObjectType):
 
 class Query(graphene.ObjectType):
     hero = graphene.Field(Character,
-                          # episode=graphene.Argument(Episode)
+                          episode=Episode()
                           )
     human = graphene.Field(Human,
                            id=graphene.String()

examples/starwars/tests/test_query.py

@@ -58,7 +58,7 @@ def test_nested_query():
             name
             friends {
               name
-              # appearsIn
+              appearsIn
               friends {
                 name
               }
@@ -72,7 +72,7 @@ def test_nested_query():
             'friends': [
                 {
                     'name': 'Luke Skywalker',
-                    # 'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
+                    'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
                     'friends': [
                         {
                             'name': 'Han Solo',
@@ -90,7 +90,7 @@ def test_nested_query():
                 },
                 {
                     'name': 'Han Solo',
-                    # 'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
+                    'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
                     'friends': [
                         {
                             'name': 'Luke Skywalker',
@@ -105,7 +105,7 @@ def test_nested_query():
                 },
                 {
                     'name': 'Leia Organa',
-                    # 'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
+                    'appearsIn': ['NEWHOPE', 'EMPIRE', 'JEDI'],
                     'friends': [
                         {
                             'name': 'Luke Skywalker',
@@ -328,21 +328,21 @@ def test_check_type_of_r2():
     assert result.data == expected
 
 
-# def test_check_type_of_luke():
-#     query = '''
-#         query CheckTypeOfLuke {
-#           hero(episode: EMPIRE) {
-#             __typename
-#             name
-#           }
-#         }
-#     '''
-#     expected = {
-#         'hero': {
-#             '__typename': 'Human',
-#             'name': 'Luke Skywalker',
-#         }
-#     }
-#     result = schema.execute(query)
-#     assert not result.errors
-#     assert result.data == expected
+def test_check_type_of_luke():
+    query = '''
+        query CheckTypeOfLuke {
+          hero(episode: EMPIRE) {
+            __typename
+            name
+          }
+        }
+    '''
+    expected = {
+        'hero': {
+            '__typename': 'Human',
+            'name': 'Luke Skywalker',
+        }
+    }
+    result = schema.execute(query)
+    assert not result.errors
+    assert result.data == expected

graphene/__init__.py

@@ -7,8 +7,9 @@ from .types import (
     Scalar,
     String, ID, Int, Float, Boolean,
     List, NonNull,
+    Enum,
     Argument
 )
 from .utils.resolve_only_args import resolve_only_args
 
-__all__ = ['ObjectType', 'Interface', 'implements', 'Field', 'Schema', 'Scalar', 'String', 'ID', 'Int', 'Float', 'Boolean', 'List','NonNull', 'Argument','resolve_only_args']
+__all__ = ['ObjectType', 'Interface', 'implements', 'Field', 'Schema', 'Scalar', 'String', 'ID', 'Int', 'Float', 'Enum', 'Boolean', 'List','NonNull', 'Argument','resolve_only_args']

graphene/types/__init__.py

@@ -3,7 +3,8 @@ from .interface import Interface
 from .scalars import Scalar, String, ID, Int, Float, Boolean
 from .schema import Schema
 from .structures import List, NonNull
+from .enum import Enum
 from .field import Field
 from .argument import Argument
 
-__all__ = ['ObjectType', 'Interface', 'implements', 'Field', 'Schema', 'Scalar', 'String', 'ID', 'Int', 'Float', 'Boolean', 'List', 'NonNull', 'Argument']
+__all__ = ['ObjectType', 'Interface', 'implements', 'Enum', 'Field', 'Schema', 'Scalar', 'String', 'ID', 'Int', 'Float', 'Boolean', 'List', 'NonNull', 'Argument']

graphene/types/enum.py

@@ -0,0 +1,76 @@
+import six
+from graphql.type import GraphQLEnumType, GraphQLEnumValue
+
+from .definitions import ClassTypeMeta, GrapheneType
+try:
+    from enum import Enum as PyEnum
+except ImportError:
+    from ..utils.enum import Enum as PyEnum
+
+from .proxy import TypeProxy
+
+
+class GrapheneEnumType(GrapheneType, GraphQLEnumType):
+    __slots__ = ('graphene_type', '_name', '_description', '_values', '_value_lookup', '_name_lookup')
+
+    def __init__(self, *args, **kwargs):
+        graphene_type = kwargs.pop('graphene_type')
+        self.graphene_type = graphene_type
+        self._name = None
+        self._description = None
+        self._values = None
+        self._value_lookup = None
+        self._name_lookup = None
+
+    def get_values(self):
+        # list of values GraphQLEnumValue
+        enum = self.graphene_type._meta.enum
+        values = []
+        for name, value in enum.__members__.items():
+            values.append(GraphQLEnumValue(name=name, value=value.value))
+        return values
+
+
+class EnumTypeMeta(ClassTypeMeta):
+
+    def get_options(cls, meta):
+        options = cls.options_class(
+            meta,
+            name=None,
+            description=None,
+            enum=None,
+            graphql_type=None,
+        )
+        options.valid_attrs = ['graphql_type', 'name', 'description', 'enum', 'abstract']
+        return options
+
+    def construct_graphql_type(cls, bases):
+        if not cls._meta.graphql_type and not cls._meta.abstract:
+            cls._meta.graphql_type = GrapheneEnumType(
+                graphene_type=cls,
+                name=cls._meta.name or cls.__name__,
+                description=cls._meta.description,
+            )
+
+    def construct(cls, bases, attrs):
+        if not cls._meta.enum:
+            cls._meta.enum = type(cls.__name__, (PyEnum,), attrs)
+        return super(EnumTypeMeta, cls).construct(bases, {})
+
+    def __call__(cls, *args, **kwargs):
+        if cls is Enum:
+            return Enum.create(PyEnum(*args, **kwargs))
+        return super(EnumTypeMeta, cls).__call__(*args, **kwargs)
+
+    def create(cls, python_enum):
+        class Meta:
+            enum = python_enum
+        return type(Meta.enum.__name__, (Enum,), {'Meta': Meta})
+
+
+class Enum(six.with_metaclass(EnumTypeMeta, TypeProxy)):
+    class Meta:
+        abstract = True
+
+    def __getattr__(self, name):
+        return getattr(self._meta.enum, name)

graphene/types/tests/test_enum.py

@@ -0,0 +1,52 @@
+from graphql.type import GraphQLEnumType, GraphQLEnumValue
+
+from ..enum import Enum
+from ..field import Field
+from ..argument import Argument
+from ...utils.enum import Enum as PyEnum
+
+
+def test_enum_construction():
+    class RGB(Enum):
+        RED = 1
+        GREEN = 2
+        BLUE = 3
+
+    assert isinstance(RGB._meta.graphql_type, GraphQLEnumType)
+    values = RGB._meta.graphql_type.get_values()
+    assert values == [
+        GraphQLEnumValue(name='RED', value=1),
+        GraphQLEnumValue(name='GREEN', value=2),
+        GraphQLEnumValue(name='BLUE', value=3),
+    ]
+    assert isinstance(RGB(name='field_name').as_field(), Field)
+    assert isinstance(RGB(name='field_name').as_argument(), Argument)
+
+
+def test_enum_instance_construction():
+    RGB = Enum('RGB', 'RED,GREEN,BLUE')
+
+    assert isinstance(RGB._meta.graphql_type, GraphQLEnumType)
+    values = RGB._meta.graphql_type.get_values()
+    assert values == [
+        GraphQLEnumValue(name='RED', value=1),
+        GraphQLEnumValue(name='GREEN', value=2),
+        GraphQLEnumValue(name='BLUE', value=3),
+    ]
+    assert isinstance(RGB(name='field_name').as_field(), Field)
+    assert isinstance(RGB(name='field_name').as_argument(), Argument)
+
+
+def test_enum_from_builtin_enum():
+    PyRGB = PyEnum('RGB', 'RED,GREEN,BLUE')
+
+    RGB = Enum.create(PyRGB)
+    assert isinstance(RGB._meta.graphql_type, GraphQLEnumType)
+    values = RGB._meta.graphql_type.get_values()
+    assert values == [
+        GraphQLEnumValue(name='RED', value=1),
+        GraphQLEnumValue(name='GREEN', value=2),
+        GraphQLEnumValue(name='BLUE', value=3),
+    ]
+    assert isinstance(RGB(name='field_name').as_field(), Field)
+    assert isinstance(RGB(name='field_name').as_argument(), Argument)

graphene/utils/enum.py

@@ -0,0 +1,837 @@
+"""Python Enumerations"""
+
+import sys as _sys
+
+__all__ = ['Enum', 'IntEnum', 'unique']
+
+version = 1, 1, 6
+
+pyver = float('%s.%s' % _sys.version_info[:2])
+
+try:
+    any
+except NameError:
+    def any(iterable):
+        for element in iterable:
+            if element:
+                return True
+        return False
+
+try:
+    from collections import OrderedDict
+except ImportError:
+    OrderedDict = None
+
+try:
+    basestring
+except NameError:
+    # In Python 2 basestring is the ancestor of both str and unicode
+    # in Python 3 it's just str, but was missing in 3.1
+    basestring = str
+
+try:
+    unicode
+except NameError:
+    # In Python 3 unicode no longer exists (it's just str)
+    unicode = str
+
+class _RouteClassAttributeToGetattr(object):
+    """Route attribute access on a class to __getattr__.
+
+    This is a descriptor, used to define attributes that act differently when
+    accessed through an instance and through a class.  Instance access remains
+    normal, but access to an attribute through a class will be routed to the
+    class's __getattr__ method; this is done by raising AttributeError.
+
+    """
+    def __init__(self, fget=None):
+        self.fget = fget
+
+    def __get__(self, instance, ownerclass=None):
+        if instance is None:
+            raise AttributeError()
+        return self.fget(instance)
+
+    def __set__(self, instance, value):
+        raise AttributeError("can't set attribute")
+
+    def __delete__(self, instance):
+        raise AttributeError("can't delete attribute")
+
+
+def _is_descriptor(obj):
+    """Returns True if obj is a descriptor, False otherwise."""
+    return (
+            hasattr(obj, '__get__') or
+            hasattr(obj, '__set__') or
+            hasattr(obj, '__delete__'))
+
+
+def _is_dunder(name):
+    """Returns True if a __dunder__ name, False otherwise."""
+    return (name[:2] == name[-2:] == '__' and
+            name[2:3] != '_' and
+            name[-3:-2] != '_' and
+            len(name) > 4)
+
+
+def _is_sunder(name):
+    """Returns True if a _sunder_ name, False otherwise."""
+    return (name[0] == name[-1] == '_' and
+            name[1:2] != '_' and
+            name[-2:-1] != '_' and
+            len(name) > 2)
+
+
+def _make_class_unpicklable(cls):
+    """Make the given class un-picklable."""
+    def _break_on_call_reduce(self, protocol=None):
+        raise TypeError('%r cannot be pickled' % self)
+    cls.__reduce_ex__ = _break_on_call_reduce
+    cls.__module__ = '<unknown>'
+
+
+class _EnumDict(dict):
+    """Track enum member order and ensure member names are not reused.
+
+    EnumMeta will use the names found in self._member_names as the
+    enumeration member names.
+
+    """
+    def __init__(self):
+        super(_EnumDict, self).__init__()
+        self._member_names = []
+
+    def __setitem__(self, key, value):
+        """Changes anything not dundered or not a descriptor.
+
+        If a descriptor is added with the same name as an enum member, the name
+        is removed from _member_names (this may leave a hole in the numerical
+        sequence of values).
+
+        If an enum member name is used twice, an error is raised; duplicate
+        values are not checked for.
+
+        Single underscore (sunder) names are reserved.
+
+        Note:   in 3.x __order__ is simply discarded as a not necessary piece
+                leftover from 2.x
+
+        """
+        if pyver >= 3.0 and key in ('_order_', '__order__'):
+            return
+        elif key == '__order__':
+            key = '_order_'
+        if _is_sunder(key):
+            if key != '_order_':
+                raise ValueError('_names_ are reserved for future Enum use')
+        elif _is_dunder(key):
+            pass
+        elif key in self._member_names:
+            # descriptor overwriting an enum?
+            raise TypeError('Attempted to reuse key: %r' % key)
+        elif not _is_descriptor(value):
+            if key in self:
+                # enum overwriting a descriptor?
+                raise TypeError('Key already defined as: %r' % self[key])
+            self._member_names.append(key)
+        super(_EnumDict, self).__setitem__(key, value)
+
+
+# Dummy value for Enum as EnumMeta explicity checks for it, but of course until
+# EnumMeta finishes running the first time the Enum class doesn't exist.  This
+# is also why there are checks in EnumMeta like `if Enum is not None`
+Enum = None
+
+
+class EnumMeta(type):
+    """Metaclass for Enum"""
+    @classmethod
+    def __prepare__(metacls, cls, bases):
+        return _EnumDict()
+
+    def __new__(metacls, cls, bases, classdict):
+        # an Enum class is final once enumeration items have been defined; it
+        # cannot be mixed with other types (int, float, etc.) if it has an
+        # inherited __new__ unless a new __new__ is defined (or the resulting
+        # class will fail).
+        if type(classdict) is dict:
+            original_dict = classdict
+            classdict = _EnumDict()
+            for k, v in original_dict.items():
+                classdict[k] = v
+
+        member_type, first_enum = metacls._get_mixins_(bases)
+        __new__, save_new, use_args = metacls._find_new_(classdict, member_type,
+                                                        first_enum)
+        # save enum items into separate mapping so they don't get baked into
+        # the new class
+        members = dict((k, classdict[k]) for k in classdict._member_names)
+        for name in classdict._member_names:
+            del classdict[name]
+
+        # py2 support for definition order
+        _order_ = classdict.get('_order_')
+        if _order_ is None:
+            if pyver < 3.0:
+                try:
+                    _order_ = [name for (name, value) in sorted(members.items(), key=lambda item: item[1])]
+                except TypeError:
+                    _order_ = [name for name in sorted(members.keys())]
+            else:
+                _order_ = classdict._member_names
+        else:
+            del classdict['_order_']
+            if pyver < 3.0:
+                _order_ = _order_.replace(',', ' ').split()
+                aliases = [name for name in members if name not in _order_]
+                _order_ += aliases
+
+        # check for illegal enum names (any others?)
+        invalid_names = set(members) & set(['mro'])
+        if invalid_names:
+            raise ValueError('Invalid enum member name(s): %s' % (
+                ', '.join(invalid_names), ))
+
+        # save attributes from super classes so we know if we can take
+        # the shortcut of storing members in the class dict
+        base_attributes = set([a for b in bases for a in b.__dict__])
+        # create our new Enum type
+        enum_class = super(EnumMeta, metacls).__new__(metacls, cls, bases, classdict)
+        enum_class._member_names_ = []               # names in random order
+        if OrderedDict is not None:
+            enum_class._member_map_ = OrderedDict()
+        else:
+            enum_class._member_map_ = {}             # name->value map
+        enum_class._member_type_ = member_type
+
+        # Reverse value->name map for hashable values.
+        enum_class._value2member_map_ = {}
+
+        # instantiate them, checking for duplicates as we go
+        # we instantiate first instead of checking for duplicates first in case
+        # a custom __new__ is doing something funky with the values -- such as
+        # auto-numbering ;)
+        if __new__ is None:
+            __new__ = enum_class.__new__
+        for member_name in _order_:
+            value = members[member_name]
+            if not isinstance(value, tuple):
+                args = (value, )
+            else:
+                args = value
+            if member_type is tuple:   # special case for tuple enums
+                args = (args, )     # wrap it one more time
+            if not use_args or not args:
+                enum_member = __new__(enum_class)
+                if not hasattr(enum_member, '_value_'):
+                    enum_member._value_ = value
+            else:
+                enum_member = __new__(enum_class, *args)
+                if not hasattr(enum_member, '_value_'):
+                    enum_member._value_ = member_type(*args)
+            value = enum_member._value_
+            enum_member._name_ = member_name
+            enum_member.__objclass__ = enum_class
+            enum_member.__init__(*args)
+            # If another member with the same value was already defined, the
+            # new member becomes an alias to the existing one.
+            for name, canonical_member in enum_class._member_map_.items():
+                if canonical_member.value == enum_member._value_:
+                    enum_member = canonical_member
+                    break
+            else:
+                # Aliases don't appear in member names (only in __members__).
+                enum_class._member_names_.append(member_name)
+            # performance boost for any member that would not shadow
+            # a DynamicClassAttribute (aka _RouteClassAttributeToGetattr)
+            if member_name not in base_attributes:
+                setattr(enum_class, member_name, enum_member)
+            # now add to _member_map_
+            enum_class._member_map_[member_name] = enum_member
+            try:
+                # This may fail if value is not hashable. We can't add the value
+                # to the map, and by-value lookups for this value will be
+                # linear.
+                enum_class._value2member_map_[value] = enum_member
+            except TypeError:
+                pass
+
+
+        # If a custom type is mixed into the Enum, and it does not know how
+        # to pickle itself, pickle.dumps will succeed but pickle.loads will
+        # fail.  Rather than have the error show up later and possibly far
+        # from the source, sabotage the pickle protocol for this class so
+        # that pickle.dumps also fails.
+        #
+        # However, if the new class implements its own __reduce_ex__, do not
+        # sabotage -- it's on them to make sure it works correctly.  We use
+        # __reduce_ex__ instead of any of the others as it is preferred by
+        # pickle over __reduce__, and it handles all pickle protocols.
+        unpicklable = False
+        if '__reduce_ex__' not in classdict:
+            if member_type is not object:
+                methods = ('__getnewargs_ex__', '__getnewargs__',
+                        '__reduce_ex__', '__reduce__')
+                if not any(m in member_type.__dict__ for m in methods):
+                    _make_class_unpicklable(enum_class)
+                    unpicklable = True
+
+
+        # double check that repr and friends are not the mixin's or various
+        # things break (such as pickle)
+        for name in ('__repr__', '__str__', '__format__', '__reduce_ex__'):
+            class_method = getattr(enum_class, name)
+            obj_method = getattr(member_type, name, None)
+            enum_method = getattr(first_enum, name, None)
+            if name not in classdict and class_method is not enum_method:
+                if name == '__reduce_ex__' and unpicklable:
+                    continue
+                setattr(enum_class, name, enum_method)
+
+        # method resolution and int's are not playing nice
+        # Python's less than 2.6 use __cmp__
+
+        if pyver < 2.6:
+
+            if issubclass(enum_class, int):
+                setattr(enum_class, '__cmp__', getattr(int, '__cmp__'))
+
+        elif pyver < 3.0:
+
+            if issubclass(enum_class, int):
+                for method in (
+                        '__le__',
+                        '__lt__',
+                        '__gt__',
+                        '__ge__',
+                        '__eq__',
+                        '__ne__',
+                        '__hash__',
+                        ):
+                    setattr(enum_class, method, getattr(int, method))
+
+        # replace any other __new__ with our own (as long as Enum is not None,
+        # anyway) -- again, this is to support pickle
+        if Enum is not None:
+            # if the user defined their own __new__, save it before it gets
+            # clobbered in case they subclass later
+            if save_new:
+                setattr(enum_class, '__member_new__', enum_class.__dict__['__new__'])
+            setattr(enum_class, '__new__', Enum.__dict__['__new__'])
+        return enum_class
+
+    def __bool__(cls):
+        """
+        classes/types should always be True.
+        """
+        return True
+
+    def __call__(cls, value, names=None, module=None, type=None, start=1):
+        """Either returns an existing member, or creates a new enum class.
+
+        This method is used both when an enum class is given a value to match
+        to an enumeration member (i.e. Color(3)) and for the functional API
+        (i.e. Color = Enum('Color', names='red green blue')).
+
+        When used for the functional API: `module`, if set, will be stored in
+        the new class' __module__ attribute; `type`, if set, will be mixed in
+        as the first base class.
+
+        Note: if `module` is not set this routine will attempt to discover the
+        calling module by walking the frame stack; if this is unsuccessful
+        the resulting class will not be pickleable.
+
+        """
+        if names is None:  # simple value lookup
+            return cls.__new__(cls, value)
+        # otherwise, functional API: we're creating a new Enum type
+        return cls._create_(value, names, module=module, type=type, start=start)
+
+    def __contains__(cls, member):
+        return isinstance(member, cls) and member.name in cls._member_map_
+
+    def __delattr__(cls, attr):
+        # nicer error message when someone tries to delete an attribute
+        # (see issue19025).
+        if attr in cls._member_map_:
+            raise AttributeError(
+                    "%s: cannot delete Enum member." % cls.__name__)
+        super(EnumMeta, cls).__delattr__(attr)
+
+    def __dir__(self):
+        return (['__class__', '__doc__', '__members__', '__module__'] +
+                self._member_names_)
+
+    @property
+    def __members__(cls):
+        """Returns a mapping of member name->value.
+
+        This mapping lists all enum members, including aliases. Note that this
+        is a copy of the internal mapping.
+
+        """
+        return cls._member_map_.copy()
+
+    def __getattr__(cls, name):
+        """Return the enum member matching `name`
+
+        We use __getattr__ instead of descriptors or inserting into the enum
+        class' __dict__ in order to support `name` and `value` being both
+        properties for enum members (which live in the class' __dict__) and
+        enum members themselves.
+
+        """
+        if _is_dunder(name):
+            raise AttributeError(name)
+        try:
+            return cls._member_map_[name]
+        except KeyError:
+            raise AttributeError(name)
+
+    def __getitem__(cls, name):
+        return cls._member_map_[name]
+
+    def __iter__(cls):
+        return (cls._member_map_[name] for name in cls._member_names_)
+
+    def __reversed__(cls):
+        return (cls._member_map_[name] for name in reversed(cls._member_names_))
+
+    def __len__(cls):
+        return len(cls._member_names_)
+
+    __nonzero__ = __bool__
+
+    def __repr__(cls):
+        return "<enum %r>" % cls.__name__
+
+    def __setattr__(cls, name, value):
+        """Block attempts to reassign Enum members.
+
+        A simple assignment to the class namespace only changes one of the
+        several possible ways to get an Enum member from the Enum class,
+        resulting in an inconsistent Enumeration.
+
+        """
+        member_map = cls.__dict__.get('_member_map_', {})
+        if name in member_map:
+            raise AttributeError('Cannot reassign members.')
+        super(EnumMeta, cls).__setattr__(name, value)
+
+    def _create_(cls, class_name, names=None, module=None, type=None, start=1):
+        """Convenience method to create a new Enum class.
+
+        `names` can be:
+
+        * A string containing member names, separated either with spaces or
+          commas.  Values are auto-numbered from 1.
+        * An iterable of member names.  Values are auto-numbered from 1.
+        * An iterable of (member name, value) pairs.
+        * A mapping of member name -> value.
+
+        """
+        if pyver < 3.0:
+            # if class_name is unicode, attempt a conversion to ASCII
+            if isinstance(class_name, unicode):
+                try:
+                    class_name = class_name.encode('ascii')
+                except UnicodeEncodeError:
+                    raise TypeError('%r is not representable in ASCII' % class_name)
+        metacls = cls.__class__
+        if type is None:
+            bases = (cls, )
+        else:
+            bases = (type, cls)
+        classdict = metacls.__prepare__(class_name, bases)
+        _order_ = []
+
+        # special processing needed for names?
+        if isinstance(names, basestring):
+            names = names.replace(',', ' ').split()
+        if isinstance(names, (tuple, list)) and isinstance(names[0], basestring):
+            names = [(e, i+start) for (i, e) in enumerate(names)]
+
+        # Here, names is either an iterable of (name, value) or a mapping.
+        item = None  # in case names is empty
+        for item in names:
+            if isinstance(item, basestring):
+                member_name, member_value = item, names[item]
+            else:
+                member_name, member_value = item
+            classdict[member_name] = member_value
+            _order_.append(member_name)
+        # only set _order_ in classdict if name/value was not from a mapping
+        if not isinstance(item, basestring):
+            classdict['_order_'] = ' '.join(_order_)
+        enum_class = metacls.__new__(metacls, class_name, bases, classdict)
+
+        # TODO: replace the frame hack if a blessed way to know the calling
+        # module is ever developed
+        if module is None:
+            try:
+                module = _sys._getframe(2).f_globals['__name__']
+            except (AttributeError, ValueError):
+                pass
+        if module is None:
+            _make_class_unpicklable(enum_class)
+        else:
+            enum_class.__module__ = module
+
+        return enum_class
+
+    @staticmethod
+    def _get_mixins_(bases):
+        """Returns the type for creating enum members, and the first inherited
+        enum class.
+
+        bases: the tuple of bases that was given to __new__
+
+        """
+        if not bases or Enum is None:
+            return object, Enum
+
+
+        # double check that we are not subclassing a class with existing
+        # enumeration members; while we're at it, see if any other data
+        # type has been mixed in so we can use the correct __new__
+        member_type = first_enum = None
+        for base in bases:
+            if  (base is not Enum and
+                    issubclass(base, Enum) and
+                    base._member_names_):
+                raise TypeError("Cannot extend enumerations")
+        # base is now the last base in bases
+        if not issubclass(base, Enum):
+            raise TypeError("new enumerations must be created as "
+                    "`ClassName([mixin_type,] enum_type)`")
+
+        # get correct mix-in type (either mix-in type of Enum subclass, or
+        # first base if last base is Enum)
+        if not issubclass(bases[0], Enum):
+            member_type = bases[0]     # first data type
+            first_enum = bases[-1]  # enum type
+        else:
+            for base in bases[0].__mro__:
+                # most common: (IntEnum, int, Enum, object)
+                # possible:    (<Enum 'AutoIntEnum'>, <Enum 'IntEnum'>,
+                #               <class 'int'>, <Enum 'Enum'>,
+                #               <class 'object'>)
+                if issubclass(base, Enum):
+                    if first_enum is None:
+                        first_enum = base
+                else:
+                    if member_type is None:
+                        member_type = base
+
+        return member_type, first_enum
+
+    if pyver < 3.0:
+        @staticmethod
+        def _find_new_(classdict, member_type, first_enum):
+            """Returns the __new__ to be used for creating the enum members.
+
+            classdict: the class dictionary given to __new__
+            member_type: the data type whose __new__ will be used by default
+            first_enum: enumeration to check for an overriding __new__
+
+            """
+            # now find the correct __new__, checking to see of one was defined
+            # by the user; also check earlier enum classes in case a __new__ was
+            # saved as __member_new__
+            __new__ = classdict.get('__new__', None)
+            if __new__:
+                return None, True, True      # __new__, save_new, use_args
+
+            N__new__ = getattr(None, '__new__')
+            O__new__ = getattr(object, '__new__')
+            if Enum is None:
+                E__new__ = N__new__
+            else:
+                E__new__ = Enum.__dict__['__new__']
+            # check all possibles for __member_new__ before falling back to
+            # __new__
+            for method in ('__member_new__', '__new__'):
+                for possible in (member_type, first_enum):
+                    try:
+                        target = possible.__dict__[method]
+                    except (AttributeError, KeyError):
+                        target = getattr(possible, method, None)
+                    if target not in [
+                            None,
+                            N__new__,
+                            O__new__,
+                            E__new__,
+                            ]:
+                        if method == '__member_new__':
+                            classdict['__new__'] = target
+                            return None, False, True
+                        if isinstance(target, staticmethod):
+                            target = target.__get__(member_type)
+                        __new__ = target
+                        break
+                if __new__ is not None:
+                    break
+            else:
+                __new__ = object.__new__
+
+            # if a non-object.__new__ is used then whatever value/tuple was
+            # assigned to the enum member name will be passed to __new__ and to the
+            # new enum member's __init__
+            if __new__ is object.__new__:
+                use_args = False
+            else:
+                use_args = True
+
+            return __new__, False, use_args
+    else:
+        @staticmethod
+        def _find_new_(classdict, member_type, first_enum):
+            """Returns the __new__ to be used for creating the enum members.
+
+            classdict: the class dictionary given to __new__
+            member_type: the data type whose __new__ will be used by default
+            first_enum: enumeration to check for an overriding __new__
+
+            """
+            # now find the correct __new__, checking to see of one was defined
+            # by the user; also check earlier enum classes in case a __new__ was
+            # saved as __member_new__
+            __new__ = classdict.get('__new__', None)
+
+            # should __new__ be saved as __member_new__ later?
+            save_new = __new__ is not None
+
+            if __new__ is None:
+                # check all possibles for __member_new__ before falling back to
+                # __new__
+                for method in ('__member_new__', '__new__'):
+                    for possible in (member_type, first_enum):
+                        target = getattr(possible, method, None)
+                        if target not in (
+                                None,
+                                None.__new__,
+                                object.__new__,
+                                Enum.__new__,
+                                ):
+                            __new__ = target
+                            break
+                    if __new__ is not None:
+                        break
+                else:
+                    __new__ = object.__new__
+
+            # if a non-object.__new__ is used then whatever value/tuple was
+            # assigned to the enum member name will be passed to __new__ and to the
+            # new enum member's __init__
+            if __new__ is object.__new__:
+                use_args = False
+            else:
+                use_args = True
+
+            return __new__, save_new, use_args
+
+
+########################################################
+# In order to support Python 2 and 3 with a single
+# codebase we have to create the Enum methods separately
+# and then use the `type(name, bases, dict)` method to
+# create the class.
+########################################################
+temp_enum_dict = {}
+temp_enum_dict['__doc__'] = "Generic enumeration.\n\n    Derive from this class to define new enumerations.\n\n"
+
+def __new__(cls, value):
+    # all enum instances are actually created during class construction
+    # without calling this method; this method is called by the metaclass'
+    # __call__ (i.e. Color(3) ), and by pickle
+    if type(value) is cls:
+        # For lookups like Color(Color.red)
+        value = value.value
+        #return value
+    # by-value search for a matching enum member
+    # see if it's in the reverse mapping (for hashable values)
+    try:
+        if value in cls._value2member_map_:
+            return cls._value2member_map_[value]
+    except TypeError:
+        # not there, now do long search -- O(n) behavior
+        for member in cls._member_map_.values():
+            if member.value == value:
+                return member
+    raise ValueError("%s is not a valid %s" % (value, cls.__name__))
+temp_enum_dict['__new__'] = __new__
+del __new__
+
+def __repr__(self):
+    return "<%s.%s: %r>" % (
+            self.__class__.__name__, self._name_, self._value_)
+temp_enum_dict['__repr__'] = __repr__
+del __repr__
+
+def __str__(self):
+    return "%s.%s" % (self.__class__.__name__, self._name_)
+temp_enum_dict['__str__'] = __str__
+del __str__
+
+if pyver >= 3.0:
+    def __dir__(self):
+        added_behavior = [
+                m
+                for cls in self.__class__.mro()
+                for m in cls.__dict__
+                if m[0] != '_' and m not in self._member_map_
+                ]
+        return (['__class__', '__doc__', '__module__', ] + added_behavior)
+    temp_enum_dict['__dir__'] = __dir__
+    del __dir__
+
+def __format__(self, format_spec):
+    # mixed-in Enums should use the mixed-in type's __format__, otherwise
+    # we can get strange results with the Enum name showing up instead of
+    # the value
+
+    # pure Enum branch
+    if self._member_type_ is object:
+        cls = str
+        val = str(self)
+    # mix-in branch
+    else:
+        cls = self._member_type_
+        val = self.value
+    return cls.__format__(val, format_spec)
+temp_enum_dict['__format__'] = __format__
+del __format__
+
+
+####################################
+# Python's less than 2.6 use __cmp__
+
+if pyver < 2.6:
+
+    def __cmp__(self, other):
+        if type(other) is self.__class__:
+            if self is other:
+                return 0
+            return -1
+        return NotImplemented
+        raise TypeError("unorderable types: %s() and %s()" % (self.__class__.__name__, other.__class__.__name__))
+    temp_enum_dict['__cmp__'] = __cmp__
+    del __cmp__
+
+else:
+
+    def __le__(self, other):
+        raise TypeError("unorderable types: %s() <= %s()" % (self.__class__.__name__, other.__class__.__name__))
+    temp_enum_dict['__le__'] = __le__
+    del __le__
+
+    def __lt__(self, other):
+        raise TypeError("unorderable types: %s() < %s()" % (self.__class__.__name__, other.__class__.__name__))
+    temp_enum_dict['__lt__'] = __lt__
+    del __lt__
+
+    def __ge__(self, other):
+        raise TypeError("unorderable types: %s() >= %s()" % (self.__class__.__name__, other.__class__.__name__))
+    temp_enum_dict['__ge__'] = __ge__
+    del __ge__
+
+    def __gt__(self, other):
+        raise TypeError("unorderable types: %s() > %s()" % (self.__class__.__name__, other.__class__.__name__))
+    temp_enum_dict['__gt__'] = __gt__
+    del __gt__
+
+
+def __eq__(self, other):
+    if type(other) is self.__class__:
+        return self is other
+    return NotImplemented
+temp_enum_dict['__eq__'] = __eq__
+del __eq__
+
+def __ne__(self, other):
+    if type(other) is self.__class__:
+        return self is not other
+    return NotImplemented
+temp_enum_dict['__ne__'] = __ne__
+del __ne__
+
+def __hash__(self):
+    return hash(self._name_)
+temp_enum_dict['__hash__'] = __hash__
+del __hash__
+
+def __reduce_ex__(self, proto):
+    return self.__class__, (self._value_, )
+temp_enum_dict['__reduce_ex__'] = __reduce_ex__
+del __reduce_ex__
+
+# _RouteClassAttributeToGetattr is used to provide access to the `name`
+# and `value` properties of enum members while keeping some measure of
+# protection from modification, while still allowing for an enumeration
+# to have members named `name` and `value`.  This works because enumeration
+# members are not set directly on the enum class -- __getattr__ is
+# used to look them up.
+
+@_RouteClassAttributeToGetattr
+def name(self):
+    return self._name_
+temp_enum_dict['name'] = name
+del name
+
+@_RouteClassAttributeToGetattr
+def value(self):
+    return self._value_
+temp_enum_dict['value'] = value
+del value
+
+@classmethod
+def _convert(cls, name, module, filter, source=None):
+    """
+    Create a new Enum subclass that replaces a collection of global constants
+    """
+    # convert all constants from source (or module) that pass filter() to
+    # a new Enum called name, and export the enum and its members back to
+    # module;
+    # also, replace the __reduce_ex__ method so unpickling works in
+    # previous Python versions
+    module_globals = vars(_sys.modules[module])
+    if source:
+        source = vars(source)
+    else:
+        source = module_globals
+    members = dict((name, value) for name, value in source.items() if filter(name))
+    cls = cls(name, members, module=module)
+    cls.__reduce_ex__ = _reduce_ex_by_name
+    module_globals.update(cls.__members__)
+    module_globals[name] = cls
+    return cls
+temp_enum_dict['_convert'] = _convert
+del _convert
+
+Enum = EnumMeta('Enum', (object, ), temp_enum_dict)
+del temp_enum_dict
+
+# Enum has now been created
+###########################
+
+class IntEnum(int, Enum):
+    """Enum where members are also (and must be) ints"""
+
+def _reduce_ex_by_name(self, proto):
+    return self.name
+
+def unique(enumeration):
+    """Class decorator that ensures only unique members exist in an enumeration."""
+    duplicates = []
+    for name, member in enumeration.__members__.items():
+        if name != member.name:
+            duplicates.append((name, member.name))
+    if duplicates:
+        duplicate_names = ', '.join(
+                ["%s -> %s" % (alias, name) for (alias, name) in duplicates]
+                )
+        raise ValueError('duplicate names found in %r: %s' %
+                (enumeration, duplicate_names)
+                )
+    return enumeration

graphene/utils/is_graphene_type.py

@@ -2,6 +2,7 @@ import inspect
 from ..types.objecttype import ObjectType
 from ..types.interface import Interface
 from ..types.scalars import Scalar
+from ..types.enum import Enum
 
 
 def is_graphene_type(_type):
@@ -9,6 +10,7 @@ def is_graphene_type(_type):
         return issubclass(_type, (
             Interface,
             ObjectType,
-            Scalar
+            Scalar,
+            Enum
         ))
     return is_graphene_type(type(_type))