Improved fields resolver

Author: syrusakbary

graphene/core/ntypes/field.py

@@ -1,4 +1,5 @@
 from collections import OrderedDict
+from functools import wraps
 
 from graphql.core.type import GraphQLField, GraphQLInputObjectField
 
@@ -29,9 +30,34 @@ def contribute_to_class(self, cls, attname):
             self.type = cls
         cls._meta.add_field(self)
 
+    @property
+    def resolver(self):
+        return self._resolver
+
+    @resolver.setter
+    def resolver(self, value):
+        self._resolver = value
+
+    def get_resolver_fn(self):
+        resolve_fn_name = 'resolve_%s' % self.attname
+        if hasattr(self.object_type, resolve_fn_name):
+            resolve_fn = getattr(self.object_type, resolve_fn_name)
+
+            @wraps(resolve_fn)
+            def custom_resolve_fn(instance, args, info):
+                return resolve_fn(instance, args, info)
+            return custom_resolve_fn
+
     def internal_type(self, schema):
-        return GraphQLField(schema.T(self.type), args=self.get_arguments(schema), resolver=self.resolver,
-                            description=self.description,)
+        resolver = self.resolver
+        description = self.description
+        if not resolver:
+            resolver = self.get_resolver_fn()
+        if not description and resolver:
+            description = resolver.__doc__
+
+        return GraphQLField(schema.T(self.type), args=self.get_arguments(schema), resolver=resolver,
+                            description=description,)
 
     def get_arguments(self, schema):
         if not self.arguments:

graphene/core/ntypes/tests/test_field.py

@@ -17,19 +17,39 @@ class Query(ObjectType):
 
     type = schema.T(field)
     assert field.name == 'myField'
+    assert field.attname == 'my_field'
     assert isinstance(type, GraphQLField)
     assert type.description == 'My argument'
     assert type.resolver == resolver
     assert type.type == GraphQLString
 
 
+def test_field_objectype_resolver():
+    field = Field(String)
+
+    class Query(ObjectType):
+        my_field = field
+
+        def resolve_my_field(self, *args, **kwargs):
+            '''Custom description'''
+            return 'RESOLVED'
+
+    schema = Schema(query=Query)
+
+    type = schema.T(field)
+    assert isinstance(type, GraphQLField)
+    assert type.description == 'Custom description'
+    assert type.resolver(Query(), {}, None) == 'RESOLVED'
+
+
 def test_field_custom_name():
     field = Field(None, name='my_customName')
 
     class MyObjectType(ObjectType):
         my_field = field
 
     assert field.name == 'my_customName'
+    assert field.attname == 'my_field'
 
 
 def test_field_custom_arguments():
@@ -57,6 +77,7 @@ class Query(ObjectType):
 
     type = schema.T(field)
     assert field.name == 'myField'
+    assert field.attname == 'my_field'
     assert isinstance(type, GraphQLInputObjectField)
     assert type.description == 'My input field'
     assert type.default_value == '3'