Modify documentation to be more clear about resolvers being static

Fixes #951

docs/execution/dataloader.rst

@@ -111,8 +111,10 @@ leaner code and at most 4 database requests, and possibly fewer if there are cac
         best_friend = graphene.Field(lambda: User)
         friends = graphene.List(lambda: User)
 
-        def resolve_best_friend(self, info):
+        @staticmethod
-            return user_loader.load(self.best_friend_id)
+        def resolve_best_friend(root, info):
+            return user_loader.load(root.best_friend_id)
 
-        def resolve_friends(self, info):
+        @staticmethod
-            return user_loader.load_many(self.friend_ids)
+        def resolve_friends(root, info):
+            return user_loader.load_many(root.friend_ids)

docs/execution/execute.rst

@@ -24,6 +24,7 @@ You can pass context to a query via ``context``.
     class Query(graphene.ObjectType):
         name = graphene.String()
 
+        @staticmethod
         def resolve_name(root, info):
             return info.context.get('name')
 
@@ -43,6 +44,7 @@ You can pass variables to a query via ``variables``.
     class Query(graphene.ObjectType):
         user = graphene.Field(User, id=graphene.ID(required=True))
 
+        @staticmethod
         def resolve_user(root, info, id):
             return get_user_by_id(id)
 

docs/execution/middleware.rst

@@ -29,6 +29,7 @@ This middleware only continues evaluation if the ``field_name`` is not ``'user'`
 .. code:: python
 
     class AuthorizationMiddleware(object):
+        @staticmethod
         def resolve(next, root, info, **args):
             if info.field_name == 'user':
                 return None

docs/quickstart.rst

@@ -40,7 +40,8 @@ one field: ``hello`` and an input name. And when we query it, it should return `
     class Query(graphene.ObjectType):
         hello = graphene.String(argument=graphene.String(default_value="stranger"))
 
-        def resolve_hello(self, info, argument):
+        @staticmethod
+        def resolve_hello(root, info, argument):
             return 'Hello ' + argument
 
     schema = graphene.Schema(query=Query)

docs/relay/connection.rst

@@ -41,5 +41,6 @@ that implements ``Node`` will have a default Connection.
         name = graphene.String()
         ships = relay.ConnectionField(ShipConnection)
 
-        def resolve_ships(self, info):
+        @staticmethod
+        def resolve_ships(root, info):
             return []

docs/types/interfaces.rst

@@ -82,6 +82,7 @@ For example, you can define a field ``hero`` that resolves to any
             episode=graphene.Int(required=True)
         )
 
+        @staticmethod
         def resolve_hero(_, info, episode):
             # Luke is the hero of Episode V
             if episode == 5:

docs/types/mutations.rst

@@ -19,7 +19,8 @@ This example defines a Mutation:
         ok = graphene.Boolean()
         person = graphene.Field(lambda: Person)
 
-        def mutate(self, info, name):
+        @staticmethod
+        def mutate(root, info, name):
             person = Person(name=name)
             ok = True
             return CreatePerson(person=person, ok=ok)
@@ -32,7 +33,8 @@ resolved.
 only argument for the mutation.
 
 **mutate** is the function that will be applied once the mutation is
-called.
+called. This function acts as a resolver function and as such is always
+called as a static method.
 
 So, we can finish our schema like this:
 
@@ -157,7 +159,8 @@ To return an existing ObjectType instead of a mutation-specific type, set the **
 
         Output = Person
 
-        def mutate(self, info, name):
+        @staticmethod
+        def mutate(root, info, name):
             return Person(name=name)
 
 Then, if we query (``schema.execute(query_str)``) the following:

docs/types/objecttypes.rst

@@ -25,6 +25,7 @@ This example model defines a Person, with a first and a last name:
         last_name = graphene.String()
         full_name = graphene.String()
 
+        @staticmethod
         def resolve_full_name(root, info):
             return '{} {}'.format(root.first_name, root.last_name)
 
@@ -72,10 +73,12 @@ passed to the ``ObjectType``.
         me = graphene.Field(Person)
         best_friend = graphene.Field(Person)
 
+        @staticmethod
         def resolve_me(_, info):
             # returns an object that represents a Person
             return get_human(name='Luke Skywalker')
 
+        @staticmethod
         def resolve_best_friend(_, info):
             return {
                 "first_name": "R2",
@@ -96,6 +99,7 @@ kwargs. For example:
     class Query(graphene.ObjectType):
         human_by_name = graphene.Field(Human, name=graphene.String(required=True))
 
+        @staticmethod
         def resolve_human_by_name(_, info, name):
             return get_human(name=name)
 
@@ -124,6 +128,7 @@ For example, given this schema:
     class Query(graphene.ObjectType):
         hello = graphene.String(required=True, name=graphene.String())
 
+        @staticmethod
         def resolve_hello(_, info, name):
             return name if name else 'World'
 
@@ -149,6 +154,7 @@ into a dict:
     class Query(graphene.ObjectType):
         hello = graphene.String(required=True, name=graphene.String())
 
+        @staticmethod
         def resolve_hello(_, info, **args):
             return args.get('name', 'World')
 
@@ -159,6 +165,7 @@ Or by setting a default value for the keyword argument:
     class Query(graphene.ObjectType):
         hello = graphene.String(required=True, name=graphene.String())
 
+        @staticmethod
         def resolve_hello(_, info, name='World'):
             return name
 
@@ -172,6 +179,7 @@ A field can use a custom resolver from outside the class:
 
     import graphene
 
+    @staticmethod
     def resolve_full_name(person, info):
         return '{} {}'.format(person.first_name, person.last_name)