graphene-django/docs/fields.rst

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Fields
======
Graphene-Django provides some useful fields to help integrate Django with your GraphQL
Schema.
DjangoListField
---------------
``DjangoListField`` allows you to define a list of :ref:`DjangoObjectType<queries-objecttypes>`'s. By default it will resolve the default queryset of the Django model.
.. code:: python
from graphene import ObjectType, Schema
from graphene_django import DjangoListField
class RecipeType(DjangoObjectType):
class Meta:
model = Recipe
fields = ("title", "instructions")
class Query(ObjectType):
recipes = DjangoListField(RecipeType)
schema = Schema(query=Query)
The above code results in the following schema definition:
.. code::
schema {
query: Query
}
type Query {
recipes: [RecipeType!]
}
type RecipeType {
title: String!
instructions: String!
}
Custom resolvers
****************
If your ``DjangoObjectType`` has defined a custom
:ref:`get_queryset<django-objecttype-get-queryset>` method, when resolving a
``DjangoListField`` it will be called with either the return of the field
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resolver (if one is defined) or the default queryset from the Django model.
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For example the following schema will only resolve recipes which have been
published and have a title:
.. code:: python
from graphene import ObjectType, Schema
from graphene_django import DjangoListField
class RecipeType(DjangoObjectType):
class Meta:
model = Recipe
fields = ("title", "instructions")
@classmethod
def get_queryset(cls, queryset, info):
# Filter out recipes that have no title
return queryset.exclude(title__exact="")
class Query(ObjectType):
recipes = DjangoListField(RecipeType)
def resolve_recipes(parent, info):
# Only get recipes that have been published
return Recipe.objects.filter(published=True)
schema = Schema(query=Query)
DjangoConnectionField
---------------------
``DjangoConnectionField`` acts similarly to ``DjangoListField`` but returns a
paginated connection following the `relay spec <https://relay.dev/graphql/connections.htm>`__
The field supports the following arguments: `first`, `last`, `offset`, `after` & `before`.