Add class property connection to SQLAlchemyObjectType (#263)

Currently to get the default connection of a `SQLAlchemyObjectType`, you have to go through `_meta`. For example, `PetType._meta.connection`. This adds a public way to get it.

graphene_sqlalchemy/converter.py

@@ -42,7 +42,7 @@ def dynamic_type():
  **field_kwargs
  )
  elif direction in (interfaces.ONETOMANY, interfaces.MANYTOMANY):
- if _type._meta.connection:
+ if _type.connection:
  # TODO Add a way to override connection_field_factory
  return connection_field_factory(relationship_prop, registry, **field_kwargs)
  return Field(

graphene_sqlalchemy/fields.py

@@ -24,10 +24,10 @@ def type(self):
  assert issubclass(_type, SQLAlchemyObjectType), (
  "SQLALchemyConnectionField only accepts SQLAlchemyObjectType types, not {}"
  ).format(_type.__name__)
- assert _type._meta.connection, "The type {} doesn't have a connection".format(
+ assert _type.connection, "The type {} doesn't have a connection".format(
  _type.__name__
  )
- return _type._meta.connection
+ return _type.connection
 
  @property
  def model(self):
@@ -115,7 +115,7 @@ def get_resolver(self, parent_resolver):
  def from_relationship(cls, relationship, registry, **field_kwargs):
  model = relationship.mapper.entity
  model_type = registry.get_type_for_model(model)
- return cls(model_type._meta.connection, resolver=get_batch_resolver(relationship), **field_kwargs)
+ return cls(model_type.connection, resolver=get_batch_resolver(relationship), **field_kwargs)
 
 
 def default_connection_field_factory(relationship, registry, **field_kwargs):

graphene_sqlalchemy/tests/test_fields.py

@@ -31,7 +31,7 @@ def resolver(_obj, _info):
  return Promise.resolve([])
 
  result = UnsortedSQLAlchemyConnectionField.connection_resolver(
- resolver, Pet._meta.connection, Pet, None, None
+ resolver, Pet.connection, Pet, None, None
  )
  assert isinstance(result, Promise)
 
@@ -51,18 +51,18 @@ def test_type_assert_object_has_connection():
 
 
 def test_sort_added_by_default():
- field = SQLAlchemyConnectionField(Pet._meta.connection)
+ field = SQLAlchemyConnectionField(Pet.connection)
  assert "sort" in field.args
  assert field.args["sort"] == Pet.sort_argument()
 
 
 def test_sort_can_be_removed():
- field = SQLAlchemyConnectionField(Pet._meta.connection, sort=None)
+ field = SQLAlchemyConnectionField(Pet.connection, sort=None)
  assert "sort" not in field.args
 
 
 def test_custom_sort():
- field = SQLAlchemyConnectionField(Pet._meta.connection, sort=Editor.sort_argument())
+ field = SQLAlchemyConnectionField(Pet.connection, sort=Editor.sort_argument())
  assert field.args["sort"] == Editor.sort_argument()
 
 

graphene_sqlalchemy/tests/test_types.py

@@ -4,6 +4,7 @@
 
 from graphene import (Dynamic, Field, GlobalID, Int, List, Node, NonNull,
  ObjectType, Schema, String)
+from graphene.relay import Connection
 
 from ..converter import convert_sqlalchemy_composite
 from ..fields import (SQLAlchemyConnectionField,
@@ -46,6 +47,15 @@ class Meta:
  assert reporter == reporter_node
 
 
+def test_connection():
+ class ReporterType(SQLAlchemyObjectType):
+ class Meta:
+ model = Reporter
+ interfaces = (Node,)
+
+ assert issubclass(ReporterType.connection, Connection)
+
+
 def test_sqlalchemy_default_fields():
  @convert_sqlalchemy_composite.register(CompositeFullName)
  def convert_composite_class(composite, registry):

graphene_sqlalchemy/types.py

@@ -325,6 +325,8 @@ def __init_subclass_with_meta__(
  _meta.connection = connection
  _meta.id = id or "id"
 
+ cls.connection = connection # Public way to get the connection
+
  super(SQLAlchemyObjectType, cls).__init_subclass_with_meta__(
  _meta=_meta, interfaces=interfaces, **options
  )