mirror of
https://github.com/graphql-python/graphene.git
synced 2024-11-23 01:56:54 +03:00
107 lines
2.6 KiB
ReStructuredText
107 lines
2.6 KiB
ReStructuredText
ObjectTypes
|
||
===========
|
||
|
||
An ObjectType is the single, definitive source of information about your
|
||
data. It contains the essential fields and behaviors of the data you’re
|
||
querying.
|
||
|
||
The basics:
|
||
|
||
- Each ObjectType is a Python class that inherits from
|
||
``graphene.ObjectType``.
|
||
- Each attribute of the ObjectType represents a ``Field``.
|
||
|
||
Quick example
|
||
-------------
|
||
|
||
This example model defines a Person, with a first and a last name:
|
||
|
||
.. code:: python
|
||
|
||
import graphene
|
||
|
||
class Person(graphene.ObjectType):
|
||
first_name = graphene.String()
|
||
last_name = graphene.String()
|
||
full_name = graphene.String()
|
||
|
||
def resolve_full_name(self, info):
|
||
return '{} {}'.format(self.first_name, self.last_name)
|
||
|
||
**first\_name** and **last\_name** are fields of the ObjectType. Each
|
||
field is specified as a class attribute, and each attribute maps to a
|
||
Field.
|
||
|
||
The above ``Person`` ObjectType has the following schema representation:
|
||
|
||
.. code::
|
||
|
||
type Person {
|
||
firstName: String
|
||
lastName: String
|
||
fullName: String
|
||
}
|
||
|
||
|
||
Resolvers
|
||
---------
|
||
|
||
A resolver is a method that resolves certain fields within a
|
||
``ObjectType``. If not specififed otherwise, the resolver of a
|
||
field is the ``resolve_{field_name}`` method on the ``ObjectType``.
|
||
|
||
By default resolvers take the arguments ``args``, ``context`` and ``info``.
|
||
|
||
NOTE: The resolvers on a ``ObjectType`` are always treated as ``staticmethod``\ s,
|
||
so the first argument to the resolver method ``self`` (or ``root``) need
|
||
not be an actual instance of the ``ObjectType``.
|
||
|
||
|
||
Quick example
|
||
~~~~~~~~~~~~~
|
||
|
||
This example model defines a ``Query`` type, which has a reverse field
|
||
that reverses the given ``word`` argument using the ``resolve_reverse``
|
||
method in the class.
|
||
|
||
.. code:: python
|
||
|
||
import graphene
|
||
|
||
class Query(graphene.ObjectType):
|
||
reverse = graphene.String(word=graphene.String())
|
||
|
||
def resolve_reverse(self, info, word):
|
||
return word[::-1]
|
||
|
||
Resolvers outside the class
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
A field can use a custom resolver from outside the class:
|
||
|
||
.. code:: python
|
||
|
||
import graphene
|
||
|
||
def reverse(root, info, word):
|
||
return word[::-1]
|
||
|
||
class Query(graphene.ObjectType):
|
||
reverse = graphene.String(word=graphene.String(), resolver=reverse)
|
||
|
||
|
||
Instances as data containers
|
||
----------------------------
|
||
|
||
Graphene ``ObjectType``\ s can act as containers too. So with the
|
||
previous example you could do:
|
||
|
||
.. code:: python
|
||
|
||
peter = Person(first_name='Peter', last_name='Griffin')
|
||
|
||
peter.first_name # prints "Peter"
|
||
peter.last_name # prints "Griffin"
|
||
|
||
.. _Interface: /docs/interfaces/
|