Rebase graphql-python#165 and resolve conflicts

Author: Joshua Cannon

graphene_sqlalchemy/converter.py

@@ -147,12 +147,25 @@ def convert_column_to_float(type, column, registry=None):
 @convert_sqlalchemy_type.register(types.Enum)
 def convert_enum_to_enum(type, column, registry=None):
     enum_class = getattr(type, 'enum_class', None)
-    if enum_class:  # Check if an enum.Enum type is used
-        graphene_type = Enum.from_enum(enum_class)
-    else:  # Nope, just a list of string options
-        items = zip(type.enums, type.enums)
-        graphene_type = Enum(type.name, items)
-    return graphene_type(
+    if enum_class:
+        enum_name = type.enum_class.__name__
+    else:
+        enum_name = type.name
+
+    enum_type = None
+    if registry is not None:
+        enum_type = registry.get_type_for_enum(enum_name)
+    if enum_type is None:
+        enum_class = getattr(type, 'enum_class', None)
+        if enum_class:  # Check if an enum.Enum type is used
+            enum_type = Enum.from_enum(enum_class)
+        else:  # Nope, just a list of string options
+            items = zip(type.enums, type.enums)
+            enum_type = Enum(enum_name, items)
+        if registry is not None:
+            registry.register_type_for_enum(enum_name, enum_type)
+
+    return enum_type(
         description=get_column_doc(column),
         required=not (is_column_nullable(column)),
     )
@@ -162,11 +175,23 @@ def convert_enum_to_enum(type, column, registry=None):
 def convert_column_to_enum(type_, column, registry=None):
     is_enum = isinstance(type_.choices, type)
     if is_enum:
-        graphene_type = Enum.from_enum(type_.choices)
+        enum_name = type_.choices.__name__
     else:
-        name = "{}_{}".format(column.table.name, column.name).upper()
-        graphene_type = Enum(name, type_.choices)
-    return graphene_type(
+        enum_name = "{}_{}".format(column.table.name, column.name).upper()
+
+    enum_type = None
+    if registry is not None:
+        enum_type = registry.get_type_for_enum(enum_name)
+
+    if enum_type is None:
+        if is_enum:
+            enum_type = Enum.from_enum(type_.choices)
+        else:
+            enum_type = Enum(enum_name, type_.choices)
+        if registry is not None:
+            registry.register_type_for_enum(enum_name, enum_type)
+
+    return enum_type(
         description=get_column_doc(column),
         required=not (is_column_nullable(column)),
     )

graphene_sqlalchemy/registry.py

@@ -3,6 +3,7 @@ def __init__(self):
         self._registry = {}
         self._registry_models = {}
         self._registry_composites = {}
+        self._registry_enums = {}
 
     def register(self, cls):
         from .types import SQLAlchemyObjectType
@@ -11,7 +12,9 @@ def register(self, cls):
             "Only classes of type SQLAlchemyObjectType can be registered, "
             'received "{}"'
         ).format(cls.__name__)
-        assert cls._meta.registry == self, "Registry for a Model have to match."
+        assert (
+            cls._meta.registry == self
+        ), "Registry for a Model have to match."
         # assert self.get_type_for_model(cls._meta.model) in [None, cls], (
         #     'SQLAlchemy model "{}" already associated with '
         #     'another type "{}".'
@@ -27,6 +30,12 @@ def register_composite_converter(self, composite, converter):
     def get_converter_for_composite(self, composite):
         return self._registry_composites.get(composite)
 
+    def register_type_for_enum(self, enum_type_name, graphene_enum):
+        self._registry_enums[enum_type_name] = graphene_enum
+
+    def get_type_for_enum(self, enum_type_name):
+        return self._registry_enums.get(enum_type_name)
+
 
 registry = None
 

graphene_sqlalchemy/tests/models.py

@@ -28,11 +28,15 @@ class Editor(Base):
     name = Column(String(100))
 
 
+PetKindEnum = Enum("cat", "dog", name="pet_kind")
+
+
 class Pet(Base):
     __tablename__ = "pets"
     id = Column(Integer(), primary_key=True)
     name = Column(String(30))
-    pet_kind = Column(Enum("cat", "dog", name="pet_kind"), nullable=False)
+    pet_kind = Column(PetKindEnum, nullable=False)
+    pet_kind_again = Column(PetKindEnum)
     hair_kind = Column(Enum(Hairkind, name="hair_kind"), nullable=False)
     reporter_id = Column(Integer(), ForeignKey("reporters.id"))